705:
for intermittent-use applications (i.e., turning off/on a hot water faucet at a sink) this can result in initially hot water, followed by a small amount of cold water as the heater re-activates, followed again by hot water. This is particularly an issue if hot water pipes are poorly insulated. The user experience is that after initially getting hot water flowing, the user turns off the valve and then a short time later turns the valve back on again. Hot water starts flowing once again at the valve from the hot water already in the piping, but at the same time, some heaters must let some amount of cold water into the piping during the reactivation time. Some time later (depending on the length of piping from the tank to the valve) this cold section of water arrives at the sink, followed shortly thereafter by hot water again. The initial thought of the user can be that the heater is failing intermittently.
715:-based) hot water recirculation systems. They may be incompatible with active hot water recirculation systems and certainly use more energy to constantly heat water within the piping, defeating one of a tankless water heater's primary advantages. On-demand recirculating pumps are often used to minimize hot water wait times from tankless water heaters and save water being wasted down the drain. On-demand recirculating pumps are activated by push-button or other sensor. A water contacting temperature probe installed at the hot water usage point signals the pump to stop. Single-cycle pumping events only occur when hot water is needed, thereby preventing the energy waste associated with constantly heating water within piping.
110:
272:
supply pipes after the flow is shut off. However, POU tankless water heaters are often installed in combination with a central water heater, since the former type have usually been limited to under 6 litres/minute (1.5 US gallons/minute), which is sufficient for only light usage. In many situations, the initial expense of buying and installing a separate POU heater for every kitchen, laundry room, bathroom, and sink can outweigh the money saved in water and energy bills. In the US, POU water heaters until recently were almost always electrical, and electricity is often substantially more expensive than
93:
result in scale build up that can block the small channels of the heat exchanger reducing efficiency and eventually cause the unit to shutdown from over heating. For this reason most manufacturers require accurate water testing and installation of a water treatment system before installing the unit and yearly descaling using permanently installed service valves. Due to the high efficiency ratings of tankless water heaters, these costs are usually offset by the energy savings and rebates from utility, state, and federal programs for installing energy efficient equipment.
743:
demand, including during the daily peak electrical load periods, which increases utility operating costs. For households using time-of-use metering (where electricity costs more during peak periods such as daytime, and is cheaper at night), a tankless electric heater may actually increase operating costs if the hot water is used during peak times. Instantaneous-type heaters are also problematic if they are connected to district heating systems, as they raise peak demands, and most utilities prefer all buildings to have hot water storage.
645:
Modern tankless are not inversely proportional, because they regulate the amount of water they heat and discharge, and therefore stabilize water temperature by using a flow control valve. Temperature change, not flow speed, is the issue the water heater must address. The wider the temperature rise, the less flow from the unit—the smaller the temperature rise, the greater the flow. The flow control valve, in conjunction with thermistors, maintains a stable temperature throughout the use of the unit.
597:
292:
waiting for use (this is called "standby loss"). In some installations, the energy lost by a tanked heater located inside a building merely helps to heat the occupied space. This is true for an electric unit, but for a gas unit some of this lost energy leaves through the exhaust vent. However, if at any time the building must be cooled to maintain comfortable temperatures, the heat lost from a hot water tank located in the conditioned space must be removed by the
20:
102:
662:
392:
211:
118:
198:
729:
from a single-lever faucet (say, when taking a shower) takes some practice. Also, when adjusting the mixture in mid-shower, the change in temperature initially reacts as a tanked heater does, but this also changes the flow rate of hot water. Therefore, some finite time later the temperature changes again very slightly and requires readjustment. This is typically not noticeable in non-shower applications.
612:
of savings. If instant hot water at taps at limited hours is a priority, a recirculation system can be accommodated by using an aquastat and timer to decrease the added heat loss from the recirculation system. If the storage tank of an electric heater is highly insulated, so that the outer surface of the tank is only slightly warmer than the ambient air, the savings with a tankless heater is less.
588:
economic design may vary according to the relative electricity, gas and water prices in the locality, the layout of the building, and how much (and when) hot water is used. Only electric tankless water heaters were widely available for many years, and they are still used for low-initial-cost POU heaters, but natural gas and propane POU heaters have now become available for consideration.
568:
736:
tanks can be positioned above the water outlets (in the loft/attic space for example) so the force of gravity can assist in delivering the water, and pumps can be added into the system to increase pressure. Power showers, for example, cannot be used with tankless systems because the tankless systems cannot deliver the hot water at a fast enough flow rate required by the pump.
580:
through the unit. This is usually done by using a flow sensor, a modulating gas valve, an inlet water temperature sensor, and an outlet water temperature sensor-choke valve. A properly configured modulating heater can supply the same output temperature of water at differing water flow rates within their rated capacity, usually maintaining a close range of ±2 °C.
177:
usually differ, and since installers will select a boiler to meet the larger demand (which is usually DHW in most homes), it will be oversized for the smaller demand; an oversized boiler will operate less efficiently due to problems such as short cycling and having increased return water temperatures that reduce efficiency. While ‘on demand’ water heating improves
169:
giving greater time and temperature control. For example, one 'combi' might supply the downstairs heating system and another the upstairs, duplication guarding against complete loss of heating and DHW in the event that one unit fails, provided that the two systems are interconnected with valves (normally closed).
611:
Though a tankless water heater typically costs more initially, it usually costs less to operate because of lower energy use—since it only heats water when required instead of continuously maintaining a tank of heated water. Even homes or buildings with high demand for hot water may realize some level
291:
In theory, tankless heaters can always be somewhat more efficient than storage tank water heaters. In both kinds of installation (centralized and POU), the absence of a tank saves energy compared to conventional tank-type water heaters, which have to reheat the water in the tank as it cools off while
176:
Disadvantages of combination systems include water flow rates inferior to a storage cylinder particularly in winter (when more hot water is used for mixing because the cold water is colder), and a requirement that overall power ratings must match peak heating requirements. The heating and DHW demands
697:
There may be a longer wait for hot water. A tankless water heater only heats water on demand, so idle water in the piping starts at room temperature. Thus, there may be a more apparent "flow delay" for hot water to reach a distant faucet (in non-point-of-use systems). Many models sold in the UK have
160:
combine the central heating with domestic hot water (DHW) in one device. When DHW is used, a combination boiler stops pumping water to the heating circuit and diverts all the boiler's power to heating DHW. Some combis have small internal water storage vessels combining the energy of the stored water
755:
Most residential demand water heaters act by modulating the heating elements to match the flow rate. This is required to prevent overheating in the heating chamber. The resulting modulation of power being used has been known to cause "fluttering" in LED fixtures. Ordinary incandescent lamps are not
742:
Tankless electric heaters, if installed in a large percentage of homes within an area, can create demand management problems for electrical utilities. Because these are high-current devices, and hot water use tends to peak at certain times of the day, their use can cause short spikes in electricity
704:
There is a short delay (1–3 seconds) between when the water begins to flow and when the heater's flow detector activates the heating elements or gas burner. In the case of continuous-use applications (showers, baths, washing machines) this is not an issue as the heater never stops heating. However,
271:
Point-of-use (POU) tankless water heaters are located immediately where the water is being used, so the water is almost instantly hot, which reduces water wastage. POU tankless heaters also can save more energy than centrally installed tankless water heaters, because no hot water is left in lengthy
92:
In order to provide on-demand, continuous hot water, tankless units use heat exchangers with many small passageways consisting of parallel plates or tubes. This increased number of passageways and small internal size create a large surface area for fast heat transfer. Unfortunately, this design can
735:
Tankless systems are reliant on the water pressure that is delivered to the property. In other words, if a tankless system is used to deliver water to a shower or water faucet, the pressure is the same as the pressure delivered to the property and cannot be increased, whereas in tanked systems the
728:
Similarly, unlike with a tank heater, the hot water temperature from a non-modulated tankless heater is inversely proportional to the rate of the water flow—the faster the flow, the less time the water spends in the heating element being heated. Mixing hot and cold water to the "right" temperature
698:
introduced a small heat store within the combination boiler to address this issue. This "keep hot" facility considerably improves the standard of hot water service, which some people otherwise find unacceptably poor with a combination boiler, but it uses considerably more fuel especially in summer.
377:
During high demand, high-flow situations, hybrid technology behaves more like a tankless heater, with high heating capacity and full modulation to supply a continuous stream of hot water across multiple applications. This produces fuel efficiencies similar to tankless heaters, but with higher flow
299:
With a central water heater of any type, any cold water standing in the pipes between the heater and the point-of-use is dumped down the drain as hot water travels from the heater. This water wastage can be avoided if a recirculator pump is installed, but at the cost of the energy to run the pump,
644:
A temperature-compensating valve tends to eliminate the issue where the temperature and pressure from tankless heaters decrease during continuous use. Most new generation tankless water heaters stabilize water pressure and temperature by a bypass valve and a mixing valve incorporated in the unit.
579:
output level; the unit is either fully on or completely off. This can cause an annoying and possibly hazardous variation of hot water temperature as the flow of water through the heater varies. Modulated tankless water heaters change their heat output in response to the flow rate of water running
168:
Combination boilers require less space than conventional tanked systems, and are significantly cheaper to install, since water tanks and associated pipes and controls are not required. Another advantage is that more than one unit may be used to supply separate heating zones or multiple bathrooms,
77:
Tankless heaters may be installed throughout a household at more than one point-of-use (POU), far from or without a central water heater, or larger centralized whole house models may still be used to provide all the hot water requirements for an entire house. The main advantages of tankless water
283:
In recent years, higher-capacity tankless heaters have become more widely available, but their feasibility may still be limited by the infrastructure's ability to furnish energy (maximum electrical amperage or gas flow rate) fast enough to meet peak hot water demand. In the past, tank-type water
651:
Tankless water heaters precisely control water temperature, which means dangerous temperature levels and spikes are less likely. An additional safety advantage stems from reduced exposure to dissolved toxic metals, which tend to occur at higher concentrations in hot water which has resided in a
369:
A gas hybrid water heater uses a modulating infrared burner that is triggered by water flow or thermostat. The multi-pass heat exchanger drives heat down then recycles it through baffled pipes for maximum efficiency. Water fills the reservoir from bottom up and spreads evenly around the heating
184:
Some designs dating from before the 21st century, notably the Ideal Sprint, included as standard a flow regulator that permitted the same model to function efficiently in both high and low pressure mains water supply areas, thus accommodating wide supply pressure variations often encountered in
587:
Under current North
American conditions, the most cost-effective configuration from an operating viewpoint often is to install a central (tank-type or tankless) water heater for most of the house, and to install a POU tankless water heater at any distant faucets or bathrooms. However, the most
373:
During low-flow situations, the hybrid behaves like a tank-type heater by having minimum fixed fuel usage and thermostat activation. Although equipped with some storage capacity, the small volume minimizes standby fuel usage. Hybrids also share additional traits with tank-type heaters like a
172:
Combination boilers are popular in Europe where market share in some countries is in excess of 70%, with a projected rise in the United
Kingdom to 78% by 2020. This trend is attributed in part by a social trend towards more numerous but smaller households and an ever-increasing trend towards
676:
Beyond the 2x-4x larger initial purchase price (as compared to a tanked water heater), installing a tankless system comes at an increased cost, particularly in retrofit applications. They tend to be particularly expensive in areas such as the US where they are not dominant, compared to the
164:
Combination boilers are rated by the DHW flow rate. The kW ratings for domestic units are typically 24 kW to 54 kW, giving approximate flow rates of 9 to 23 litres (2.4 to 6.1 US gal) per minute. Larger units are used in commercial and institutional applications, or for
188:
While combination boilers have more moving parts and are thus widely held to be less reliable than tank systems, the twin trends towards replacement of parts based on a pre-set design life and replaceable digital controls for 'traditional' systems has largely eroded this distinction.
690:
10 or 8 wire, corresponding to 5.5 or 8.5 mm for typical POU (point of use) heaters at North
American voltages. Larger whole-house electric units may require up to AWG 2 wire. In gas appliances, both pressure and volume requirements must be met for optimum
330:
Hybrids have small storage tanks that temper incoming cold water. Thus they only have to increase water temperature from warm to hot, unlike tankless which has to raise completely cold water to hot. The defining characteristics of a "hybrid water heater" are:
624:
Though flow rate determines the amount of hot water the heater can produce, it can deliver it at that flow rate indefinitely. However, this can also be an ecological disadvantage, as running out of hot water limits use, but a tankless heater provides no such
816:
Drosou, Vassiliki N.; Tsekouras, Panagiotis D.; Oikonomou, Th. I.; Kosmopoulos, Panos I.; Karytsas, Constantine S. (2014-01-01). "The HIGH-COMBI project: High solar fraction heating and cooling systems with combination of innovative components and methods".
300:
plus the energy to reheat the water recirculated through the pipes. Some recirculating systems reduce standby loss by operating only at select times—turning off late at night, for example. This saves energy at the expense of greater system complexity.
631:
Most tankless water heaters can be mounted on a wall or internally in a building's structure. This means less physical space must be dedicated to heating water. Even systems that can't be mounted on walls take up less space than a tank-type water
721:
Tankless water heaters often have minimum flow requirements before the heater is activated, and this can result in a gap between the cold water temperature, and the coolest warm water temperature that can be achieved with a hot and cold water
681:
or gas pipeline to handle the load, and replace the existing vent pipe—possibly adding expense to the retrofit. Many tankless units have fully modulating gas valves that range from as low as 10,000 to over 1,000,000
583:
A high-efficiency condensing combination boiler provides both space heating and water heating, and is an increasingly popular choice in UK houses, accounting for over half of all new domestic boilers installed.
66:
that instantly heat water as it flows through the device, and do not retain any water internally except for what is in the heat exchanger coil unless the unit is equipped with an internal buffer tank.
105:
Tankless gas electronic ignition water heaters. Gas water heaters have an exhaust vent or one to two exhaust pipes on the top, and still require electric power for electronics, sensing and ignition.
113:
A three-phase, 21 kW, 400-volt tankless water heater in Europe, with new
European color coding for three-phase power. There are also heaters that use several single-phase circuits instead
316:. It maintains water pressure and consistent supply of hot water across multiple hot water applications, and like its tankless cousins, it is efficient and can supply a continuous flow of hot
575:
Tankless water heaters can be further divided into two categories according to their heating capability: "full on/full off" versus "modulated". Full on/full off units do not have a variable
2092:
141:
and is warmed by gas or electrical heating. Since there is no finite tank of hot water that can be depleted, the heater provides a continuous supply. To protect the units in
145:
environments, durable coatings or other surface treatments are available. Acid-resistant coatings are capable of withstanding temperatures of 1000 °C.
374:
floor-standing installation, standard PVC venting, draining pan, and they can be installed with a recirculation pump for even more water efficiency.
845:
749:
In case of a power outage, tankless heaters cannot supply hot water, unlike tank based heaters which can supply the hot water stored in the tank.
78:
heaters are a plentiful, practically limitless continuous flow of hot water (as compared to a limited flow of continuously heated hot water from
86:
under some conditions due to the use of energy only when in use, and the elimination of standby energy losses since there is no hot water tank.
89:
The main disadvantage of these systems other than their high initial costs (equipment and installation) is the required yearly maintenance.
2217:
181:, the volume of water available at any given moment is limited, and the design of a 'combi' must be matched to the water supply pressure.
677:
established tank design. If a storage water heater is replaced with a tankless one, the installer may have to increase the size of the
638:
No stored water means there is no risk of water damage from a tank failure or rupture, though pipe or fitting failure remains possible.
323:
The hybrid approach is designed to eliminate general shortcomings of other technologies. For example, hybrids are activated by either
911:
74:
and ease of fabrication. However, copper heat exchangers are more susceptible to scale buildup than stainless steel heat exchangers.
23:
The inside of a hydraulically operated two-stage tankless heater, heated by single-phase electric power. The copper tank contains
413:
232:
2308:
890:
2052:
2323:
1003:
1047:
1372:
618:
Users in remote points in the building do not have to run the hot water as long, waiting for it to get to the faucet.
439:
258:
421:
240:
2328:
2290:
2210:
2102:
711:
Since a tankless water heater is inactive when hot water is not being used, they are incompatible with passive (
417:
309:
236:
284:
heaters have been used to compensate for lower energy delivery capacities, and they are still useful when the
109:
863:
756:
similarly affected since the temperature of a tungsten element does not react to high-frequency modulations.
1663:
978:
792:
2659:
2203:
1826:
1628:
766:
1608:
1453:
1438:
953:
1713:
138:
67:
1443:
1082:
402:
221:
2566:
1648:
1643:
1352:
1294:
1274:
406:
225:
308:
A hybrid water heater is a water heating system that integrates technology traits from both the
2536:
2485:
2445:
2250:
2169:
2112:
1841:
1811:
1142:
1040:
134:
2694:
313:
2470:
2343:
2338:
2154:
2107:
1863:
1806:
1791:
1263:
285:
2645:
2601:
2571:
2333:
2240:
1853:
1422:
1330:
1232:
178:
161:
and the gas or oil burner to give faster DHW at the taps or to increase the DHW flow rate.
79:
71:
8:
2664:
2640:
2465:
2368:
2353:
2275:
2245:
2184:
2042:
1683:
1279:
687:
452:
The table below compares the efficiencies of different types of tankless water heating.
2618:
2591:
2510:
2138:
2037:
1959:
1796:
1761:
1658:
1638:
1533:
1508:
1309:
1202:
1072:
571:
Electric point-of-use (POU) tankless water heater, wall-mounted under a sink (Germany)
165:
multiple-unit dwellings. High flow-rate models can simultaneously supply two showers.
2285:
2270:
2174:
2097:
1786:
1633:
1618:
1538:
1518:
1483:
1336:
1299:
1197:
1033:
2723:
2654:
2551:
2391:
2260:
2179:
1944:
1753:
1703:
1528:
1448:
1407:
1367:
1127:
1092:
826:
293:
342:(typically between 2 US gallons (7.6 L; 1.7 imp gal) to 20 gallons)
2611:
2606:
2586:
2576:
2531:
2515:
2490:
2440:
2396:
2348:
2265:
2255:
2007:
1883:
1873:
1573:
1523:
1513:
1493:
1473:
1397:
1289:
1212:
1187:
678:
576:
530:
137:
is used to bring water to the target temperature. The water circulates through a
24:
370:
pipes, producing continuous hot water with consistent pressure and temperature.
2596:
2581:
2546:
2475:
2455:
2430:
2415:
2318:
2047:
2017:
2012:
1964:
1898:
1728:
1723:
1548:
1543:
1387:
1325:
1269:
1217:
1152:
1097:
929:
830:
339:
288:
may have a limited capacity, often reflected in peak demand energy surcharges.
201:
Electric point-of-use (POU) tankless water heater, or electric shower (Britain)
83:
335:
A combination of the water flow capacity of a tank, and efficiency of tankless
2717:
2450:
2401:
2280:
2164:
2128:
1997:
1934:
1603:
1503:
1412:
1304:
1284:
1112:
1107:
513:
2480:
2460:
2363:
2057:
1974:
1914:
1893:
1888:
1801:
1776:
1718:
1698:
1688:
1673:
1613:
1598:
1568:
1553:
1488:
1468:
1417:
1362:
1227:
1207:
1137:
868:
596:
63:
2435:
2373:
2313:
2226:
2002:
1979:
1954:
1939:
1831:
1708:
1693:
1678:
1623:
1593:
1588:
1578:
1563:
1558:
1478:
1463:
1237:
1177:
350:
273:
130:
122:
669:
On the other hand, tankless water heaters also have some disadvantages:
19:
2635:
2500:
2420:
2062:
1949:
1929:
1816:
1781:
1743:
1738:
1583:
1458:
1222:
1182:
712:
324:
101:
2093:
International
Association of Plumbing and Mechanical Officials (IAPMO)
661:
16:
Water heaters that instantly heat water as it flows through the device
2623:
2495:
2358:
2067:
1924:
1919:
1858:
1392:
1357:
1320:
1192:
1157:
1122:
1117:
1087:
358:
391:
210:
2673:
2629:
2541:
2406:
2133:
1821:
1167:
1147:
1102:
1077:
1056:
1004:"Are your lights flickering? Check possible causes before you call"
815:
117:
2561:
2425:
2072:
1969:
1878:
1766:
1668:
1498:
1402:
1382:
1258:
771:
354:
296:
system, thus requiring larger cooling capacity and energy usage.
277:
2410:
2159:
1868:
1836:
1342:
1315:
1172:
1162:
652:
conventional water heater tank for significant periods of time.
197:
2195:
2650:
2556:
1771:
1733:
1377:
1347:
790:
317:
2669:
1848:
1653:
1242:
1132:
1025:
567:
142:
683:
185:
otherwise similar urban settings such as
Greater London.
129:
The heater is normally turned off, but is equipped with
28:
357:), or be electrically powered using a combination of
133:
which activate it when water travels through them. A
345:
Dual activation: flow sensing and thermostat control
906:
904:
327:(similar to tanked) or flow (similar to tankless).
192:
173:physically smaller and often high density housing.
70:are preferred in these units because of their high
338:Built-in small storage water reservoir as part of
2715:
901:
891:"Hybrid Water Heater Technology - HowStuffWorks"
604:Tankless water heaters provide many advantages:
740:Time-of-use metering and peak electrical loads:
2211:
1041:
948:
946:
861:
864:"The new boiler that's causing a heated row"
686:. Most electrical tankless heaters require
600:Mobile water heater in a train car (Russia)
420:. Unsourced material may be challenged and
361:and conventional electric heating element.
239:. Unsourced material may be challenged and
2218:
2204:
1048:
1034:
943:
440:Learn how and when to remove this message
259:Learn how and when to remove this message
819:Renewable and Sustainable Energy Reviews
726:Maintaining constant shower temperature:
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116:
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18:
2699:Mastropiero Plumbing & Heating Corp
2103:Plumbing & Drainage Institute (PDI)
979:"Tankless or Demand-Type Water Heaters"
954:"Tankless or Demand-Type Water Heaters"
349:Hybrid water heaters can be gas-fired (
303:
280:(when the latter fuels are available).
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1001:
148:
2199:
1029:
2053:Mechanical, electrical, and plumbing
418:adding citations to reliable sources
385:
237:adding citations to reliable sources
204:
791:International Protective Coatings.
733:Operation with low supply pressure:
13:
2687:
843:
665:Gas tankless water heater (Taiwan)
556:249–260 °C (480–500 °F)
553:199–210 °C (390–410 °F)
14:
2735:
1373:Push-to-pull compression fittings
2329:Failure of electronic components
656:
550:53–68 °C (128–155 °F)
390:
209:
193:Point-of-use (POU) water heaters
2225:
995:
862:Phillip Inman (April 2, 2005).
121:Tankless gas water heater with
80:conventional tank water heaters
971:
922:
883:
855:
837:
809:
784:
719:Achieving cooler temperatures:
364:
1:
1002:Sutton, Samuel (2020-05-22).
912:"Hybrid Technology Explained"
777:
636:Reduced risk of water damage:
591:
381:
2324:List of emerging electronics
2113:World Plumbing Council (WPC)
1664:Reduced pressure zone device
1055:
930:"UK.DIY Combination Boilers"
96:
7:
2108:Uniform Plumbing Code (UPC)
1827:Instant hot water dispenser
1629:Piping and plumbing fitting
960:. U.S. Department of Energy
767:Instant hot water dispenser
760:
562:
454:
10:
2740:
1454:Backflow prevention device
1439:Atmospheric vacuum breaker
831:10.1016/j.rser.2013.08.019
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2233:
2147:
2121:
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1988:
1907:
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1714:Thermostatic mixing valve
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1063:
642:Temperature compensation:
609:Long term energy savings:
1444:Automatic bleeding valve
1083:Compatibility (chemical)
797:www.international-pc.com
753:LED Light Strobe effect:
60:instant-on water heaters
2695:"Tankless Water Heater"
2567:Electromagnetic warfare
1649:Pressure-balanced valve
1644:Pressure vacuum breaker
1353:Pipe (fluid conveyance)
1295:Drain-waste-vent system
1275:Chemical drain cleaners
793:"Temperature Resistant"
310:tank-type water heaters
2537:Automotive electronics
2486:Robotic vacuum cleaner
2446:Information technology
2251:Electronic engineering
2170:Template:Public health
1842:water recycling shower
1812:Hot water storage tank
1143:Onsite sewage facility
709:Recirculation systems:
666:
601:
572:
314:tankless water heaters
202:
135:negative feedback loop
126:
114:
106:
68:Copper heat exchangers
36:Tankless water heaters
32:
2471:Portable media player
2344:Molecular electronics
2339:Low-power electronics
2155:Fire sprinkler system
1864:Tankless water heater
1807:Garbage disposal unit
1792:Electric water boiler
1264:British Standard Pipe
664:
616:Savings in water use:
599:
570:
286:energy infrastructure
200:
139:copper heat exchanger
120:
112:
104:
22:
2665:Terahertz technology
2646:Open-source hardware
2602:Consumer electronics
2572:Electronics industry
2334:Flexible electronics
2241:Analogue electronics
1854:Storage water heater
1423:Water heat recycling
1331:National Pipe Thread
1233:Water supply network
629:Less physical space:
622:Unlimited hot water:
414:improve this section
304:Hybrid water heaters
233:improve this section
72:thermal conductivity
2641:Nuclear electronics
2466:Networking hardware
2369:Quantum electronics
2354:Organic electronics
2276:Printed electronics
2246:Digital electronics
2185:Template:Wastewater
2043:Hydrostatic testing
1684:Rooftop water tower
1280:Compression fitting
149:Combination boilers
2619:Marine electronics
2592:Integrated circuit
2511:Video game console
2309:2020s in computing
2291:Thermal management
2139:Waterborne disease
2038:Hydronic balancing
1797:Evaporative cooler
1762:Accessible bathtub
1659:Radiator (heating)
1639:Pressure regulator
1534:Double check valve
1509:Concentric reducer
1310:Garden Hose Thread
1203:Thermal insulation
1073:Air gap (plumbing)
846:"UK Market Update"
667:
602:
573:
203:
127:
115:
107:
33:
2683:
2682:
2660:Radio electronics
2286:Schematic capture
2271:Power electronics
2193:
2192:
2175:Template:Sewerage
2122:Health and safety
2098:NSF International
1908:Specialized tools
1787:Drinking fountain
1754:Plumbing fixtures
1634:Plug (sanitation)
1619:Nipple (plumbing)
1539:Eccentric reducer
1519:Coupling (piping)
1484:Chemigation valve
1337:Nominal Pipe Size
1300:Ductile iron pipe
1198:Thermal expansion
916:reevesjournal.com
702:Intermittent-use:
679:electrical wiring
560:
559:
450:
449:
442:
269:
268:
261:
179:energy efficiency
82:), and potential
2731:
2709:
2708:
2706:
2705:
2691:
2655:Radio navigation
2552:Data acquisition
2261:Microelectronics
2220:
2213:
2206:
2197:
2196:
2180:Template:Toilets
1945:Flare-nut wrench
1704:Submersible pump
1529:Dielectric union
1449:Automatic faucet
1408:Thread seal tape
1368:Plastic pipework
1128:Hydrostatic loop
1093:Drain (plumbing)
1050:
1043:
1036:
1027:
1026:
1018:
1017:
1015:
1014:
999:
993:
992:
990:
989:
975:
969:
968:
966:
965:
950:
941:
940:
938:
937:
926:
920:
919:
908:
899:
898:
887:
881:
880:
878:
877:
859:
853:
852:
850:
841:
835:
834:
813:
807:
806:
804:
803:
788:
533:emissions (PPM)
516:emissions (PPM)
455:
445:
438:
434:
431:
425:
394:
386:
294:air conditioning
264:
257:
253:
250:
244:
213:
205:
25:heating elements
2739:
2738:
2734:
2733:
2732:
2730:
2729:
2728:
2714:
2713:
2712:
2703:
2701:
2693:
2692:
2688:
2684:
2679:
2612:Small appliance
2607:Major appliance
2587:Home automation
2577:Embedded system
2532:Audio equipment
2520:
2516:Washing machine
2441:Home theater PC
2397:Central heating
2392:Air conditioner
2384:
2378:
2349:Nanoelectronics
2301:
2295:
2266:Optoelectronics
2256:Instrumentation
2229:
2224:
2194:
2189:
2143:
2117:
2085:
2083:
2077:
2030:
2028:
2022:
2008:Pressure sensor
1990:
1984:
1960:Plumber's snake
1903:
1884:Water dispenser
1874:Washing machine
1748:
1574:Flushing trough
1524:Diaphragm valve
1514:Condensate pump
1494:Circulator pump
1474:Butterfly valve
1427:
1398:Solvent welding
1290:Crimp (joining)
1247:
1213:Trap (plumbing)
1188:Surface tension
1065:
1059:
1054:
1022:
1021:
1012:
1010:
1000:
996:
987:
985:
977:
976:
972:
963:
961:
952:
951:
944:
935:
933:
932:. Diyfaq.org.uk
928:
927:
923:
910:
909:
902:
889:
888:
884:
875:
873:
860:
856:
848:
844:Eljidi, Abdel.
842:
838:
814:
810:
801:
799:
789:
785:
780:
763:
695:Start-up delay:
659:
594:
565:
531:Carbon monoxide
446:
435:
429:
426:
411:
395:
384:
367:
306:
265:
254:
248:
245:
230:
214:
195:
151:
99:
44:continuous flow
17:
12:
11:
5:
2737:
2727:
2726:
2711:
2710:
2685:
2681:
2680:
2678:
2677:
2676:Communications
2667:
2662:
2657:
2648:
2643:
2638:
2633:
2627:
2621:
2616:
2615:
2614:
2609:
2604:
2597:Home appliance
2594:
2589:
2584:
2582:Home appliance
2579:
2574:
2569:
2564:
2559:
2554:
2549:
2547:Control system
2544:
2539:
2534:
2528:
2526:
2522:
2521:
2519:
2518:
2513:
2508:
2503:
2498:
2493:
2488:
2483:
2478:
2473:
2468:
2463:
2458:
2456:Microwave oven
2453:
2448:
2443:
2438:
2433:
2428:
2423:
2418:
2413:
2404:
2399:
2394:
2388:
2386:
2380:
2379:
2377:
2376:
2371:
2366:
2361:
2356:
2351:
2346:
2341:
2336:
2331:
2326:
2321:
2319:Bioelectronics
2316:
2311:
2305:
2303:
2297:
2296:
2294:
2293:
2288:
2283:
2278:
2273:
2268:
2263:
2258:
2253:
2248:
2243:
2237:
2235:
2231:
2230:
2223:
2222:
2215:
2208:
2200:
2191:
2190:
2188:
2187:
2182:
2177:
2172:
2167:
2162:
2157:
2151:
2149:
2145:
2144:
2142:
2141:
2136:
2131:
2125:
2123:
2119:
2118:
2116:
2115:
2110:
2105:
2100:
2095:
2089:
2087:
2084:organizations
2079:
2078:
2076:
2075:
2070:
2065:
2060:
2055:
2050:
2048:Leak detection
2045:
2040:
2034:
2032:
2024:
2023:
2021:
2020:
2018:Water metering
2015:
2013:Water detector
2010:
2005:
2000:
1994:
1992:
1986:
1985:
1983:
1982:
1977:
1972:
1967:
1965:Plumber wrench
1962:
1957:
1952:
1947:
1942:
1937:
1932:
1927:
1922:
1917:
1911:
1909:
1905:
1904:
1902:
1901:
1899:Water softener
1896:
1891:
1886:
1881:
1876:
1871:
1866:
1861:
1856:
1851:
1846:
1845:
1844:
1834:
1829:
1824:
1819:
1814:
1809:
1804:
1799:
1794:
1789:
1784:
1779:
1774:
1769:
1764:
1758:
1756:
1750:
1749:
1747:
1746:
1741:
1736:
1731:
1729:Vacuum ejector
1726:
1724:Vacuum breaker
1721:
1716:
1711:
1706:
1701:
1696:
1691:
1686:
1681:
1676:
1671:
1666:
1661:
1656:
1651:
1646:
1641:
1636:
1631:
1626:
1621:
1616:
1611:
1606:
1601:
1596:
1591:
1586:
1581:
1576:
1571:
1566:
1561:
1556:
1551:
1549:Faucet aerator
1546:
1544:Expansion tank
1541:
1536:
1531:
1526:
1521:
1516:
1511:
1506:
1501:
1496:
1491:
1486:
1481:
1476:
1471:
1466:
1461:
1456:
1451:
1446:
1441:
1435:
1433:
1429:
1428:
1426:
1425:
1420:
1415:
1410:
1405:
1400:
1395:
1390:
1388:Sewage pumping
1385:
1380:
1375:
1370:
1365:
1360:
1355:
1350:
1345:
1340:
1334:
1328:
1326:Leak detection
1323:
1318:
1313:
1307:
1302:
1297:
1292:
1287:
1282:
1277:
1272:
1270:Cast iron pipe
1267:
1261:
1255:
1253:
1249:
1248:
1246:
1245:
1240:
1235:
1230:
1225:
1220:
1218:Venturi effect
1215:
1210:
1205:
1200:
1195:
1190:
1185:
1180:
1175:
1170:
1165:
1160:
1155:
1153:Sanitary sewer
1150:
1145:
1140:
1135:
1130:
1125:
1120:
1115:
1110:
1105:
1100:
1098:Drinking water
1095:
1090:
1085:
1080:
1075:
1069:
1067:
1061:
1060:
1053:
1052:
1045:
1038:
1030:
1020:
1019:
994:
970:
942:
921:
900:
882:
854:
836:
808:
782:
781:
779:
776:
775:
774:
769:
762:
759:
758:
757:
750:
744:
737:
730:
723:
716:
706:
699:
692:
674:Startup costs:
658:
655:
654:
653:
646:
639:
633:
626:
619:
613:
593:
590:
564:
561:
558:
557:
554:
551:
548:
547:Exhaust temp.
544:
543:
540:
537:
534:
527:
526:
523:
520:
517:
510:
509:
506:
503:
500:
496:
495:
492:
489:
486:
482:
481:
478:
475:
472:
468:
467:
464:
461:
458:
448:
447:
398:
396:
389:
383:
380:
366:
363:
347:
346:
343:
340:heat exchanger
336:
305:
302:
267:
266:
217:
215:
208:
194:
191:
150:
147:
98:
95:
84:energy savings
38:— also called
31:maximum power.
27:with 7.2
15:
9:
6:
4:
3:
2:
2736:
2725:
2722:
2721:
2719:
2700:
2696:
2690:
2686:
2675:
2671:
2668:
2666:
2663:
2661:
2658:
2656:
2652:
2649:
2647:
2644:
2642:
2639:
2637:
2634:
2631:
2628:
2625:
2622:
2620:
2617:
2613:
2610:
2608:
2605:
2603:
2600:
2599:
2598:
2595:
2593:
2590:
2588:
2585:
2583:
2580:
2578:
2575:
2573:
2570:
2568:
2565:
2563:
2560:
2558:
2555:
2553:
2550:
2548:
2545:
2543:
2540:
2538:
2535:
2533:
2530:
2529:
2527:
2523:
2517:
2514:
2512:
2509:
2507:
2504:
2502:
2499:
2497:
2494:
2492:
2489:
2487:
2484:
2482:
2479:
2477:
2474:
2472:
2469:
2467:
2464:
2462:
2459:
2457:
2454:
2452:
2449:
2447:
2444:
2442:
2439:
2437:
2434:
2432:
2429:
2427:
2424:
2422:
2419:
2417:
2414:
2412:
2408:
2405:
2403:
2402:Clothes dryer
2400:
2398:
2395:
2393:
2390:
2389:
2387:
2381:
2375:
2372:
2370:
2367:
2365:
2362:
2360:
2357:
2355:
2352:
2350:
2347:
2345:
2342:
2340:
2337:
2335:
2332:
2330:
2327:
2325:
2322:
2320:
2317:
2315:
2312:
2310:
2307:
2306:
2304:
2298:
2292:
2289:
2287:
2284:
2282:
2281:Semiconductor
2279:
2277:
2274:
2272:
2269:
2267:
2264:
2262:
2259:
2257:
2254:
2252:
2249:
2247:
2244:
2242:
2239:
2238:
2236:
2232:
2228:
2221:
2216:
2214:
2209:
2207:
2202:
2201:
2198:
2186:
2183:
2181:
2178:
2176:
2173:
2171:
2168:
2166:
2165:Template:HVAC
2163:
2161:
2158:
2156:
2153:
2152:
2150:
2146:
2140:
2137:
2135:
2132:
2130:
2129:Plumbing code
2127:
2126:
2124:
2120:
2114:
2111:
2109:
2106:
2104:
2101:
2099:
2096:
2094:
2091:
2090:
2088:
2086:and standards
2080:
2074:
2071:
2069:
2066:
2064:
2061:
2059:
2056:
2054:
2051:
2049:
2046:
2044:
2041:
2039:
2036:
2035:
2033:
2025:
2019:
2016:
2014:
2011:
2009:
2006:
2004:
2001:
1999:
1998:Control valve
1996:
1995:
1993:
1987:
1981:
1978:
1976:
1973:
1971:
1968:
1966:
1963:
1961:
1958:
1956:
1953:
1951:
1948:
1946:
1943:
1941:
1938:
1936:
1935:Drain cleaner
1933:
1931:
1928:
1926:
1923:
1921:
1918:
1916:
1913:
1912:
1910:
1906:
1900:
1897:
1895:
1892:
1890:
1887:
1885:
1882:
1880:
1877:
1875:
1872:
1870:
1867:
1865:
1862:
1860:
1857:
1855:
1852:
1850:
1847:
1843:
1840:
1839:
1838:
1835:
1833:
1830:
1828:
1825:
1823:
1820:
1818:
1815:
1813:
1810:
1808:
1805:
1803:
1800:
1798:
1795:
1793:
1790:
1788:
1785:
1783:
1780:
1778:
1775:
1773:
1770:
1768:
1765:
1763:
1760:
1759:
1757:
1755:
1751:
1745:
1742:
1740:
1737:
1735:
1732:
1730:
1727:
1725:
1722:
1720:
1717:
1715:
1712:
1710:
1707:
1705:
1702:
1700:
1697:
1695:
1692:
1690:
1687:
1685:
1682:
1680:
1677:
1675:
1672:
1670:
1667:
1665:
1662:
1660:
1657:
1655:
1652:
1650:
1647:
1645:
1642:
1640:
1637:
1635:
1632:
1630:
1627:
1625:
1622:
1620:
1617:
1615:
1612:
1610:
1607:
1605:
1604:Hose coupling
1602:
1600:
1597:
1595:
1592:
1590:
1587:
1585:
1582:
1580:
1577:
1575:
1572:
1570:
1567:
1565:
1562:
1560:
1557:
1555:
1552:
1550:
1547:
1545:
1542:
1540:
1537:
1535:
1532:
1530:
1527:
1525:
1522:
1520:
1517:
1515:
1512:
1510:
1507:
1505:
1504:Closet flange
1502:
1500:
1497:
1495:
1492:
1490:
1487:
1485:
1482:
1480:
1477:
1475:
1472:
1470:
1467:
1465:
1462:
1460:
1457:
1455:
1452:
1450:
1447:
1445:
1442:
1440:
1437:
1436:
1434:
1430:
1424:
1421:
1419:
1416:
1414:
1413:Threaded pipe
1411:
1409:
1406:
1404:
1401:
1399:
1396:
1394:
1391:
1389:
1386:
1384:
1381:
1379:
1376:
1374:
1371:
1369:
1366:
1364:
1361:
1359:
1356:
1354:
1351:
1349:
1346:
1344:
1341:
1338:
1335:
1332:
1329:
1327:
1324:
1322:
1319:
1317:
1314:
1311:
1308:
1306:
1305:Flare fitting
1303:
1301:
1298:
1296:
1293:
1291:
1288:
1286:
1285:Copper tubing
1283:
1281:
1278:
1276:
1273:
1271:
1268:
1265:
1262:
1260:
1257:
1256:
1254:
1250:
1244:
1241:
1239:
1236:
1234:
1231:
1229:
1226:
1224:
1221:
1219:
1216:
1214:
1211:
1209:
1206:
1204:
1201:
1199:
1196:
1194:
1191:
1189:
1186:
1184:
1181:
1179:
1176:
1174:
1171:
1169:
1166:
1164:
1161:
1159:
1156:
1154:
1151:
1149:
1146:
1144:
1141:
1139:
1136:
1134:
1131:
1129:
1126:
1124:
1121:
1119:
1116:
1114:
1113:Grade (slope)
1111:
1109:
1108:Friction loss
1106:
1104:
1101:
1099:
1096:
1094:
1091:
1089:
1086:
1084:
1081:
1079:
1076:
1074:
1071:
1070:
1068:
1062:
1058:
1051:
1046:
1044:
1039:
1037:
1032:
1031:
1028:
1024:
1009:
1005:
998:
984:
980:
974:
959:
955:
949:
947:
931:
925:
917:
913:
907:
905:
897:. 2009-03-10.
896:
895:HowStuffWorks
892:
886:
871:
870:
865:
858:
847:
840:
832:
828:
824:
820:
812:
798:
794:
787:
783:
773:
770:
768:
765:
764:
754:
751:
748:
747:Power outage:
745:
741:
738:
734:
731:
727:
724:
720:
717:
714:
710:
707:
703:
700:
696:
693:
689:
685:
680:
675:
672:
671:
670:
663:
657:Disadvantages
650:
647:
643:
640:
637:
634:
630:
627:
623:
620:
617:
614:
610:
607:
606:
605:
598:
589:
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514:Nitrous oxide
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249:November 2015
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218:This section
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158:combi boilers
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94:
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64:water heaters
61:
57:
53:
49:
45:
41:
40:instantaneous
37:
30:
26:
21:
2702:. Retrieved
2698:
2689:
2525:Applications
2506:Water heater
2505:
2481:Refrigerator
2461:Mobile phone
2364:Piezotronics
2058:Pipe marking
2031:and services
2027:Professions,
1975:Strap wrench
1915:Basin wrench
1894:Water heater
1889:Water filter
1802:Flush toilet
1777:Dehumidifier
1719:Trench drain
1699:Street elbow
1689:Safety valve
1674:Relief valve
1614:Needle valve
1599:Grinder pump
1569:Flow limiter
1554:Float switch
1489:Chopper pump
1469:Booster pump
1418:Tube bending
1363:Pipe support
1228:Water hammer
1208:Thermosiphon
1138:Neutral axis
1023:
1011:. Retrieved
1007:
997:
986:. Retrieved
982:
973:
962:. Retrieved
958:Energy Saver
957:
934:. Retrieved
924:
915:
894:
885:
874:. Retrieved
869:The Guardian
867:
857:
839:
822:
818:
811:
800:. Retrieved
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673:
668:
648:
641:
635:
628:
621:
615:
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603:
586:
582:
574:
508:average 60%
505:average 80%
502:average 86%
480:natural gas
477:natural gas
474:natural gas
451:
436:
427:
412:Please help
400:
376:
372:
368:
348:
329:
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255:
246:
231:Please help
219:
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152:
131:flow sensors
128:
125:for ignition
91:
88:
76:
59:
55:
51:
47:
43:
39:
35:
34:
2632:electronics
2436:Home cinema
2374:Spintronics
2314:Atomtronics
2227:Electronics
2003:Flow sensor
1991:and control
1989:Measurement
1980:Tap and die
1955:Pipe wrench
1940:Driving cap
1832:Laundry tub
1709:Tap (valve)
1694:Sewage pump
1679:Riser clamp
1624:Pinch valve
1594:Grease trap
1589:Globe valve
1579:Flushometer
1564:Floor drain
1559:Float valve
1479:Check valve
1464:Bleed screw
1238:Water table
1178:Storm sewer
1064:Fundamental
825:: 463–472.
499:Efficiency
351:natural gas
320:on demand.
274:natural gas
154:Combination
123:pilot light
2704:2023-01-01
2636:Multimedia
2626:technology
2501:Television
2431:Home robot
2421:Dishwasher
2383:Electronic
2063:Pipefitter
1950:Pipecutter
1930:Core drill
1817:Humidifier
1782:Dishwasher
1744:Zone valve
1739:Water tank
1584:Gate valve
1459:Ball valve
1432:Components
1252:Technology
1223:Wastewater
1183:Stormwater
1013:2024-08-04
988:2023-12-16
983:Energy.gov
964:2019-07-12
936:2009-04-23
876:2011-04-08
802:2017-04-22
778:References
713:convection
691:operation.
592:Advantages
494:cast iron
488:cast iron
430:April 2017
382:Efficiency
378:capacity.
325:thermostat
2624:Microwave
2496:Telephone
2385:equipment
2359:Photonics
2082:Industry
2068:Pipelayer
1925:Borescope
1920:Blowtorch
1859:Sump pump
1393:Soldering
1358:Pipe dope
1321:Hydronics
1193:Tap water
1158:Sewer gas
1123:Heat trap
1118:Greywater
1088:Corrosion
485:Material
463:Tankless
401:does not
365:Operation
359:heat pump
220:does not
97:Operation
56:on-demand
2718:Category
2674:Wireless
2630:Military
2562:e-health
2542:Avionics
2411:Notebook
2407:Computer
2300:Advanced
2234:Branches
2148:See also
2134:Scalding
1822:Icemaker
1609:Manifold
1168:Sewerage
1148:Pressure
1103:Fuel gas
1078:Backflow
1066:concepts
1057:Plumbing
872:. London
761:See also
563:Controls
542:200–250
539:190–200
312:and the
2724:Heaters
2426:Freezer
2073:Plumber
2029:trades,
1970:Plunger
1879:Washlet
1767:Bathtub
1669:Reducer
1499:Cistern
1403:Swaging
1383:Sealant
1259:Brazing
772:Quooker
649:Safety:
632:heater.
491:copper
460:Hybrid
422:removed
407:sources
355:propane
278:propane
241:removed
226:sources
2557:e-book
2491:Tablet
2451:Cooker
2416:Camera
2302:topics
2160:Piping
1869:Urinal
1837:Shower
1343:O-ring
1316:Gasket
1173:Siphon
1163:Sewage
625:limit.
536:40–45
525:60–90
522:30–40
143:acidic
62:— are
48:inline
2670:Wired
2651:Radar
2476:Radio
1772:Bidet
1734:Valve
1378:Putty
1348:Oakum
1339:(NPS)
1333:(NPT)
1312:(GHT)
1266:(BSP)
849:(PDF)
577:power
519:5–30
471:Fuel
466:Tank
318:water
58:, or
52:flash
2672:and
2653:and
1849:Sink
1654:Pump
1243:Well
1133:Leak
722:mix.
684:BTUs
405:any
403:cite
224:any
222:cite
1008:PEC
827:doi
688:AWG
416:by
353:or
276:or
235:by
156:or
2720::
2697:.
1006:.
981:.
956:.
945:^
914:.
903:^
893:.
866:.
823:29
821:.
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833:.
829::
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428:(
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256:(
251:)
247:(
243:.
229:.
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