Need a recommendation on which tankless is right - looking through the Stiebel Eltron brochure, they give a chart with regional water temps and devices in line. This will service a small bathroom (sink only), a wash basin and a kitchenette sink. Wash basin will likely be the water hog and may also have a hot/cold hose bib. Would 2.5gpm cover the needs - like the Tempra 20?
Help sizing tankless electric water heater
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Originally Posted by The_Eric
Need a recommendation on which tankless is right - looking through the Stiebel Eltron brochure, they give a chart with regional water temps and devices in line. This will service a small bathroom (sink only), a wash basin and a kitchenette sink. Wash basin will likely be the water hog and may also have a hot/cold hose bib. Would 2.5gpm cover the needs - like the Tempra 20?
To size up you have to think of how many gpm would you need if they were operating all at once, even if it will never happen.
Need a recommendation on which tankless is right - looking through the Stiebel Eltron brochure, they give a chart with regional water temps and devices in line. This will service a small bathroom (sink only), a wash basin and a kitchenette sink. Wash basin will likely be the water hog and may also have a hot/cold hose bib. Would 2.5gpm cover the needs - like the Tempra 20?
To size up you have to think of how many gpm would you need if they were operating all at once, even if it will never happen.
JHZR2
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Youre ONLY providing water to a bathroom with it? And more specifically, only to sinks for handwashing? Does the kitchenette sink get more strenuous use? Will more than one be routinely operating?
If so, I believe sinks are restricted to what, 1.5GPM? If so, that should be fine.
Id look at the aerator on your sink spout, that should state your design flow. Better yet, measure it.
Realize that you wont be running it full hot, so probably only need 2/3 of the design flow...
Its not like youre going to have multiple people showering in the winter.
If so, I believe sinks are restricted to what, 1.5GPM? If so, that should be fine.
Id look at the aerator on your sink spout, that should state your design flow. Better yet, measure it.
Realize that you wont be running it full hot, so probably only need 2/3 of the design flow...
Its not like youre going to have multiple people showering in the winter.
The chart is based on 105 F outlet temperature, which is typical for bathroom sinks, but you likely want hotter for filling mop buckets or washing cars.
These feature an automatic valve which will reduce flow rate to maintain the set output temperature.
The larger models aren't much more expensive but much of the total installed cost is in wiring and potential breaker box upgrades to get electricity to the unit.
These feature an automatic valve which will reduce flow rate to maintain the set output temperature.
The larger models aren't much more expensive but much of the total installed cost is in wiring and potential breaker box upgrades to get electricity to the unit.
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i have one for quite a while 220V serving only me in Pa everything close to the unit. would need to check the book wherever it is but i called them after looking + thinking what i would need. more is better as the winter comes + intake is colder you must run it slower to meet the requested temperature.
Do you have natural gas or propane to the house ? If so a whole house tankless water heater might be an option. I used Bosch and they have some sizing charts available online.
I would think 2.5 GPM would be fine.
What size power is there? What does the 2.5 GPM one take?
A small electric tank water heater would be an option also. Some at around 10 gallons are 110V.
What size power is there? What does the 2.5 GPM one take?
A small electric tank water heater would be an option also. Some at around 10 gallons are 110V.
This isn't for a house - more of a man cave type installation, so no showers, washers or other hot water consuming devices.
The wash basin will be the biggest consumer and will require the hottest water. If it were mine, I'd use a small electric tank unit, but it's not. There is gas but the decision was made to run one of these.. Its still in the construction phase so electricity is isn't an issue either.
Mk378, good point about the temp output. We'll have to go out and browse prices and size up a little
The wash basin will be the biggest consumer and will require the hottest water. If it were mine, I'd use a small electric tank unit, but it's not. There is gas but the decision was made to run one of these.. Its still in the construction phase so electricity is isn't an issue either.
Mk378, good point about the temp output. We'll have to go out and browse prices and size up a little
The electric tankless does draw a lot of electricity, so make sure to size the circuits properly. The energy savings for a tankless is found in two ways: you are not storing and heating 20-80 gallons of water for on-demand use, and it can also provide for endless hot water, so there is no need to turn up the hot water tank to 160 F just to make sure the bathtub can be filled when the Princess wants a soak in the tub.
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