Heat Pump Water Heaters

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I'm going to keep my eye out on a sale or just bite.
Keep in mind, Menards generally has at least one sale per year on those that is better than all the rest...save an additional $200 or so...usually somewheres in the July/August range IIRC...
 
How would you set up two heaters so that one would heat the other via thermosiphon
Well, every install would probably be a little different I'm sure...and it depends somewhat on where the water connections are on the tanks you are using...but the basics are that hot water will rise and cold water will fall...so you plumb it so that can happen...might need to raise one of the tanks up some to give enough rise/fall to the plumbing to make it work well...notice the pipe connections are on the side of the Richmond HPWH, and kinda low, so that helps...might need to use the drain line connector of the storage tank to tee into the cold water inlet of the HPWH(?)...if you do an internet search for water heater thermosiphon storage, something along those lines, there's tons of info/ideas out there
Edit, made a crude drawing...no laughing...this is the idea...might need to tweak things a bit, like add a check valve on the cold water return to the HPWH, stuff like that, etc.
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I was just reading the technical data sheet on the Richmond HPWH from Menards. What are your thoughts on the ducted options? Is there ever a time you would want to intake or exhaust air from/to the attic? How about connecting the intake to a wood furnace? Just rambling here....
I did some thinking about the most efficient way to duct. My conclusion was that if you were interested in the dehumidifying intake and exhaust must be in from/ out to your conditioned space. You may be able to to run I a. It more efficiency during the summer by intaking warm outside air but you exhaust it inside you are pressuring the conditioned space and forcing your cold air out. If you reverse that during to winter you will need to make up air from outside and it most of the time would be colder than the exhaust temp. I am considering intake from the the conditioned basement and exhaust it up stairs. my basement is always colder than the main floor so this would help the basement stay warmer in the winter (some) and the main floor be cooler in the summer. As a related point here is an infrared picture of my heater closet. Intake is outside the closet at the ceiling of the room and exhaust is just ducted pointed to the floor of the closet with louvered doors. So you can see the thermal gradient ( no scale here but I’m guessing is about 5-7 degrees different from top of closet to the bottom).
If you have an open basement door would not bother ducting unless you have a warm room upstairs in the summer. If you are in a smaller space ( mine said rooms less that 700 cubic ft) that’s when you needed to utilize the ducts 6604B8ED-C0CE-46C0-B334-B0987A509781.jpeg
 
I haven't messed around with ducting my HPWH out of the room, yet...just have an extension on the intake to pull the warmest air off the ceiling, and an elbow on the exhaust port to point it at the wood furnace 10-12' away...it gets quite the convective loop going in the winter! I have a piece of paper hanging from the door frame between the two units and it will be laying at close to a 45* angle when things are rolling good.
I did notice in the literature that these new Richmonds are a bit different than mine...you have to buy their adapter to hook ducts up now...mine has a little flange that 8" duct pipe slides right onto...
 
I wondered before if anybody offers a fridge/water heater combo...heat from the fridge goes into the water, cool from the water goes into the fridge...I'd think it could be done with 1 compressor unit too...would just need a line set between the 2 units...
Sounds like a good idea for small apts . They already have a combo Stove sink and fridge in one.
 
It just so happens that our water heater is directly below our refrigerator, that doesn't seem like a bad idea. My oldest son brought home kill-o-watt meter and at a maximum output on his PC, it drew 365 watts. When he put it in sleep mode, it was 3 watts....so that's not too bad. I have a clamp ammeter and I'm currently investigating some of the usage, however I still suspect the water heater.
Any new findings?
 
Not yet. There's some tight wires in the panel and recently I started removing the old line mortar from the fieldstone foundation and repointing. Every weekend and evening after work. It's been wearing me out.
 
In thinking about this a bit more, in addition to making sure your well pump is not running more than it needs to (for one of several possible reasons) I'm sure you are probably on a septic system out there...if you have an aerator motor in the tank, need to make sure that it is not wound up with hair, rags, etc...it happens, and that will make a dent in the ole electric bill...also should check to see if the aerator is on a timer, they often are, and it could fail "on"...although they do often fail "off" too...that causes different problems :rolleyes:
 
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With nightly bath tub soaks by multiple residents and your hard working bones, have you considered a hot tub? They’re awesome. Then a shower to be clean.

Admittedly the modern spas require a surprisingly small amount of power too but they don’t overload your septic, your water heater, and you might actually save power plus gain immense enjoyment. Bonus, you can actually talk to your family since phones don’t mix with water!
 
In thinking about this a bit more, in addition to making sure your well pump is not running more than it needs to (for one of several possible reasons) I'm sure you are probably on a septic system out there...if you have an aerator motor in the tank, need to make sure that it is not wound up with hair, rags, etc...it happens, and that will make a dent in the ole electric bill...also should check to see if the aerator is on a timer, they often are, and it could fail "on"...although they do often fail "off" too...that causes different problems :rolleyes:
Unfortunately we have an old septic system with no aerator. I suspect here in the future we will need a new system.....yikes! I have thought about the well, however we have a newer poly line and up to about 2 or so years ago upgraded from an old jet pump to a submersible. Going from 20-40 to 50-70 with the well. I upgraded the well system not only due to maintenance but for savings. The old system had a 3/4 hp pump that would run forever to get up to 40 pounds.
 
With nightly bath tub soaks by multiple residents and your hard working bones, have you considered a hot tub? They’re awesome. Then a shower to be clean.

Admittedly the modern spas require a surprisingly small amount of power too but they don’t overload your septic, your water heater, and you might actually save power plus gain immense enjoyment. Bonus, you can actually talk to your family since phones don’t mix with water!

Don't go there lol. My wife wants either an extension to the pool deck or the patio on the pool for a hot tub. I've been avoiding the thing like the plague since I mainly take care of the pool. I've heard horror stories with our friends having 150.00 or more in excess with usage from a spa.
 
Don't go there lol. My wife wants either an extension to the pool deck or the patio on the pool for a hot tub. I've been avoiding the thing like the plague since I mainly take care of the pool. I've heard horror stories with our friends having 150.00 or more in excess with usage from a spa.

Modern spas are much better. My consumption is of little value for comparison due to climate and lower cost electric but for giggles it’s under 2$ per day in winter. My tub is from 2003 and seriously lacks insulation but has been very dependable and chemicals are super easy. We’re 3 times a week type people.
 
I've been working on drying the basement and repointing the old stone foundation on half of our basement. With all the work I've put in, I decided to purchase an 80 gallon heatpump waterheater from Menards. It's a 220 30 amp 80 gallon model. The benefits of dehumidifying the basement and saving money make the purchase worth it. I'm predicted to get the heater by the 17th of April. Once I install the heater I'll update the thread.
 
Can I hear any pros or cons to brands. I was all for ao smith but now I’m leaning towards rheem. No menards around here. Home Depot, Lowes and plumbing supply places
 
Can I hear any pros or cons to brands. I was all for ao smith but now I’m leaning towards rheem. No menards around here. Home Depot, Lowes and plumbing supply places

I had a State HPWH in my old house. No problems with it in the time I owned it. The installer told me they had previously used Steibel Eltron units but started seeing a high failure rate a few years back and switched to the State brand.
 
Can I hear any pros or cons to brands. I was all for ao smith but now I’m leaning towards rheem. No menards around here. Home Depot, Lowes and plumbing supply places
AOSmith and State are the same company. I was impressed that AOSmith actually honored their warranty, so that says something about them as a company. I bought my unit from Ferguson plumbing supply. Personally, I’d buy the unit with the highest COP, the least amount of noise for the least amount of money. I’d say they all are pretty much the same internally.
 
Thanks fellas, the plumbing supply place told me the same about state owning ao smith. Just based off the reviews, ao Smith support seems lacking when there is a problem. I’ve read them is quieter compared to ao, also no WiFi. I’ll obsess over this a few more weeks.
 
I ended up with an 80 gallon Bradford white HPWH. Been running 12 months only complaint it the filter seems inadequate but that’s easy to address. I’m happy with it.

Evan
 
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Thanks fellas, the plumbing supply place told me the same about state owning ao smith. Just based off the reviews, ao Smith support seems lacking when there is a problem. I’ve read them is quieter compared to ao, also no WiFi. I’ll obsess over this a few more weeks.
I’d agree that their support was lacking until I got someone on the phone that had a clue. Once I got the correct person on the phone, the support was stellar. Getting the replacement HPHW was a very seamless process too.

IMHO - it’s no different than buying a car. All of the manufacturers suck, you just need to figure out which one sucks less.
 
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So I'll be installing the new water heater this weekend. Since the joists are basically touching the top of the unit, I'll need to restructure to give proper clearances (minimum). What I am wondering about is currently I have a peak load management system on the current heater and I'm unsure if those types of systems are compatible. I feel I should remove the peak buster since the new unit is much more efficient. Either way I'm excited and can't wait to see the results.
 
So I'll be installing the new water heater this weekend. Since the joists are basically touching the top of the unit, I'll need to restructure to give proper clearances (minimum). What I am wondering about is currently I have a peak load management system on the current heater and I'm unsure if those types of systems are compatible. I feel I should remove the peak buster since the new unit is much more efficient. Either way I'm excited and can't wait to see the results.

I am assuming the peak load system is managed by your utility company?? I guessing the heatpump uses about 500-700 watts. Don’t see it being useful. The power off-on startup routine on mine runs through a self diagnostic. Takes several minutes to complete. I would prefer not to have routine power disruptions to but it probably would not hurt anything.

I don’t have full 8’ ceilings but didn’t have a clearance issues but I am wondering how one would change out the anode rod? Tip it over?


Evan
 
I would think so unless the heater had a flexible anode rod. Says it has a premium magnesium anode with resistor. I did confirm with a friend who works for our Co-op that confirmed the peakbuster is not compatible (which I figured). I read that load management boxes could actually cause the heater to consume more energy if the water temp fell too much and the elements kicked in. With the unit having active monitoring and Wifi I'll get to see how much our hot water costs.
 
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I am assuming the peak load system is managed by your utility company?? I guessing the heatpump uses about 500-700 watts. Don’t see it being useful. The power off-on startup routine on mine runs through a self diagnostic. Takes several minutes to complete. I would prefer not to have routine power disruptions to but it probably would not hurt anything.

I don’t have full 8’ ceilings but didn’t have a clearance issues but I am wondering how one would change out the anode rod? Tip it over?


Evan
Break/bend the old one as it comes out.
Install a multi-sectioned one. They look kind of like nunchucks.
 
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