Where to Put a Heat Pump Water Heater
We are in the middle of a remodel and trying to decide on a bunch of equipment fighting for the same minimal amount of floor space. Our plans did not account for our efficiency goals which I developed when I had ample time to read/learn while waiting for delayed permits due to pandemic slowdowns).
I want to go with a HPWH, and due to noise concerns, I am leaning toward paying the extra money for the Sanden.
I initially planned to put the tank in a second-floor laundry room (garage below, so no concern over water leak/damage and easy access to run pipes to 1st floor). However, that might be the only place for me to locate an HRV (unless I go ductless on those).
So the question is if I locate the tank in the garage, is there any significant performance hit or downside due to that space being unconditioned or the fact that I will be within about 1-2ft of the max vertical distance between HP and tank?
https://www.eco2waterheater.com/_files/ugd/e88920_99d56741bd484af6b2db8544daa14d12.pdf
The laundry room seemed reasonable as we will have three bathrooms on the 2nd floor and one bath and kitchen on the first, meaning the water source is closer to the bathrooms, and the tank is much closer to the heat pump on the flat roof. All of this is a non-issue if I go with a ductless HRV (likely Lunos), but if possible, I would like to make that decision independent of the water heater. That said, if the tank needs to be in the laundry room, I guess it means I don’t have to waste tons of time stressing over the HRV as my decision will be made for me. I’ll likely post separate HRV questions if I have any, but happy to provide more details on the project if relevant to help out here.
Thanks,
Doug
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Replies
We were in a similar situation with our remodel. We bought the Sanden, and had to locate the outdoor unit 50-55 feet from the tank. The specified maximum distance was 50 feet, so we talked to Sanden about it. They confirmed that the limit was based on the strength of the pump, and we got the impression it would probably work fine at that distance. It does.
We also put the tank in a semi-conditioned basement.
As you know, both long pipe runs and cool air around the tank will decrease efficiency. I doubt that the effect would be "significant", but that might depend on a number of other factors (like climate, and whether or not the pipe run is itself in conditioned space). Sorry if that isn't much help, but for what it's worth it doesn't seem like an unreasonable plan to me.
What is your climate zone?
Hey Michael,
We are in Los Angeles so I think that is climate zone 3. I would say on the coldest days the garage never gets below 47 or so. The garage is attached, it is actually the first floor for half of our house so it never really gets too hot as it is completely shaded and it never gets colder than the worst LA temps. I also suspect that post remodel with our new insulation (there was none) the rest of the conditioned house will help keep the garage warmer even though it won't be within our air sealing. There is one large shared wall with our living room and the ceiling of the garage is bedrooms and bathrooms.
Kevin, that is helpful to hear, thanks for sharing. I'm pretty sure our overall distance will be under the limit even after any strange routes we might need to take to connect the roof to the garage. Was mostly concerned about the vertical rise (pump power) and if having the tank in the garage would eat into the efficiency.
I also realized after I posted that although the Sanden unit is great I could go with another HPWH if I'm putting it in the garage anyway. Probably a performance loss but a much easier and cheaper project.
thanks for the replies.