Heat Pump Water Heater

Joined
Jun 12, 2004
Messages
4,144
Location
Athens, GA
I've been thinking recently that the water heater in our house is probably getting near end-of-life and that I'd rather replace it on my time rather than waiting for something to fail and then being up against the wall to get it done. Had been doing some reading lately on heat pump water heaters and it seems like the technology can save some serious energy costs over the length of its life. That and my local EMC is giving a $500 rebate on the units led me to pull the trigger last night on ordering one from Home Depot and having it shipped to my place.

Ended up at $1143 shipped to my front porch (Before rebate) for the 50 Gallon Rheem Hybrid unit.. Will have another $200 or so in installation costs as I'll replace the expansion tank and will need a condensate pump and a set of PEX crimpers and some other hardware to install it. One of the upsides to me is that the unit sits in my garage, so the heat pump will actually be pumping cool, dry air into the garage space in the summertime which is a south-facing garage, so it is extremely hot in the summer, which will be win-win all around for that system.

(The Hybrid unit also has standard water heater elements in it so that in extremely cold weather or if the heat pump fails, it works exactly like a normal electric water heater. They can also be used to boost output if you run into a situation where you need a lot of hot water for a longer time)

We use a ton of hot water in our house, so I'm figuring at most a 2 year ROI for it with some quick and dirty math.

Anyone else have one in their place and how has it been for you?
 
I've had 2, my first a rheem came with the house. it had circuit board failure that was covered.. kept tripping.. probably got damaged by hilljack installers. It was also old generation. but worked great.. before rusting out at the pipes due to improper installation with bad unions. lasted 8 years. Died early not its fault.

Current one is Signature Premier 50-Gallon AO SMITH. Cost was under 300$ self installed. then 300$ federal tax credit.
love how it dehumidifies my basement and makes hot water basically free vs running a dehumidifier.
Cold air is great in summer.. in winter its not a plus but the furnace takes care of it with cheap natural gas heating.

I keep mine in heat pump only mode. it can take a few hours to recover if you drain it all the way down.

heat pump vs the conventional electric I had I save around 20-25$ a month on electricity not counting what I would use with a dehumidifier 9 months out of the year.
I never run out of hot water except if I run hot water clothes in the washer , take hot shower, and wife showers after with shaving legs etc.. but it recovers overnight.. probably 3-4 hours in winter with heat pump only mode. never timed it exactly.. my groundwater is also alot colder than yours.

Dont forget your federal tax rebate next year $300

Obviously it more efficient when your garage is 100f, but it should work reliably to under 40f easily.
 
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Check with your local and state governments in addition to the federal rebates. Lots of places have tax rebates for upgrading to these. I know a couple people that have them now and they've saved them a ton of money over the traditional resistive heating HWH. I'd have to ask them but $20-$25/mo like Rand said sounds about right. These things are a game changer honestly. I can't wait for hybrid heat pump electric clothes driers to become more common. There's one or two out there but they aren't commonplace yet.
 
I've been thinking recently that the water heater in our house is probably getting near end-of-life and that I'd rather replace it on my time rather than waiting for something to fail and then being up against the wall to get it done. Had been doing some reading lately on heat pump water heaters and it seems like the technology can save some serious energy costs over the length of its life. That and my local EMC is giving a $500 rebate on the units led me to pull the trigger last night on ordering one from Home Depot and having it shipped to my place.

Ended up at $1143 shipped to my front porch (Before rebate) for the 50 Gallon Rheem Hybrid unit.. Will have another $200 or so in installation costs as I'll replace the expansion tank and will need a condensate pump and a set of PEX crimpers and some other hardware to install it. One of the upsides to me is that the unit sits in my garage, so the heat pump will actually be pumping cool, dry air into the garage space in the summertime which is a south-facing garage, so it is extremely hot in the summer, which will be win-win all around for that system.

(The Hybrid unit also has standard water heater elements in it so that in extremely cold weather or if the heat pump fails, it works exactly like a normal electric water heater. They can also be used to boost output if you run into a situation where you need a lot of hot water for a longer time)

We use a ton of hot water in our house, so I'm figuring at most a 2 year ROI for it with some quick and dirty math.

Anyone else have one in their place and how has it been for you?
How did you get it so cheap? On HD website its $1699
 
How did you get it so cheap? On HD website its $1699

Mine was $225 price mistake/website shenanigans at lowes.

If they offered one that didnt have resistive heating and used a 115v cord it would be even easier.. they make them but super $$$ for some reason.
 
To the OP, was natural gas available in the area? Also, how many gallons of water do you want to heat? Inlet temp and outlet temp and electricity price and you can do the math. That rebate certainly helps things.
 
Check with your local and state governments in addition to the federal rebates. Lots of places have tax rebates for upgrading to these. I know a couple people that have them now and they've saved them a ton of money over the traditional resistive heating HWH. I'd have to ask them but $20-$25/mo like Rand said sounds about right. These things are a game changer honestly. I can't wait for hybrid heat pump electric clothes driers to become more common. There's one or two out there but they aren't commonplace yet.
Check with your electric company, too. Mine gives rebates on several kinds of appliances. I got $50 rebates on two $100 air purifiers last year.
 
How did you get it so cheap? On HD website its $1699
Set your location to Hagerstown, MD, and then ship it to your door. It let me go through the process and submitted the order. They haven't canceled it or changed it. If they do, I'm no worse off than before. Also, if it doesn't work and the price difference stays the same, I'll pick one up on my way home from PA when I go in a couple of months.


HD Rec.jpg
 
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To the OP, was natural gas available in the area? Also, how many gallons of water do you want to heat? Inlet temp and outlet temp and electricity price and you can do the math. That rebate certainly helps things.
for me i cant self install a powervent natural gas heater.(well I didnt want to.) Cost installed was 2300 cost at home depot around $1200, cost installed by plumber $2900

Cost for my hybrid is cheaper than running a natural gas water heater + dehumidifier.. the recovery is about 6-8x slower in full heat pump mode vs gas.

Set your location to Hagerstown, MD, and then ship it to your door. It let me go through the process and submitted the order. They haven't canceled it or changed it. If they do, I'm no worse off than before. Also, if it doesn't work and the price difference stays the same, I'll pick one up on my way home from PA when I go in a couple of months.

I ordered from california lowes got 1000$ instant savings.. then paid truck shipping it came from store 10miles away.. to be even cheaper I could have picked it up in person but its a 200lb unit I wanted the guys to put it in my basement so I didnt get hernia.
I also stacked it with 18% CC +fuelperks so mine ended up being 300-18% -300 tax rebate.

SUPER HAPPY with mine.
But for those that already have a natural gas water heater. I would just replace with a natural gas unit.
 
To the OP, was natural gas available in the area? Also, how many gallons of water do you want to heat? Inlet temp and outlet temp and electricity price and you can do the math. That rebate certainly helps things.
Nope, no gas here. Heat pump would still be way more efficient in this climate. Replacing a standard element style electric with the heat pump model.
 
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Nope, no gas here. Heat pump would still be way more efficient in this climate.
There is eff. then there is cost for energy.
Natural gas blows away resistive electricity but when the heat pump is 25% of the energy vs resistive.
its very competitive..

and when its heat pump vs resistive or propane/oil.... heat pump is amazing.

Some random numbers using my costs..

1,037,000 Btu of natural gas costs me $3.31+ distro fees call it 4$
I have to have gas hookup for furnace..

1kwh is about 17cents and 3400 btu
That is about 305kwh to heat

natural gas is about 80% efficient in water heater so in actual heating
vs resistive electric(100% efficient)

41.48 for electric 4$ for gas.

heat pump around 10-20$ electric(depends on how much heat pump runs vs resistive) vs 4$ gas.
can also subtract if its saving you electricity by not running a dehumidifier (in my case this saves a ton)
Free garage cooling is a decent perk..

Now that doesnt include my monthly get porked by the gas company 36$ connection fee.. but have to have that for furnace.
the numbers for GAS FREE ctech bob are different of course.

You can always oversize to an 80gallon tank if you need more water.
In GA where a heat pump for home heat makes sense.. and/or no gas is available.. Heat pump water heater is really a game changer.
 
There is eff. then there is cost for energy.
Natural gas blows away resistive electricity but when the heat pump is 25% of the energy vs resistive.
its very competitive..

and when its heat pump vs resistive or propane/oil.... heat pump is amazing.

Some random numbers using my costs..

1,037,000 Btu of natural gas costs me $3.31+ distro fees call it 4$
I have to have gas hookup for furnace..

1kwh is about 17cents and 3400 btu
That is about 305kwh to heat

natural gas is about 80% efficient in water heater so in actual heating
vs resistive electric(100% efficient)

41.48 for electric 4$ for gas.

heat pump around 10-20$ electric(depends on how much heat pump runs vs resistive) vs 4$ gas.
can also subtract if its saving you electricity by not running a dehumidifier (in my case this saves a ton)
Free garage cooling is a decent perk..

Now that doesnt include my monthly get porked by the gas company 36$ connection fee.. but have to have that for furnace.
the numbers for GAS FREE ctech bob are different of course.

You can always oversize to an 80gallon tank if you need more water.
In GA where a heat pump for home heat makes sense.. and/or no gas is available.. Heat pump water heater is really a game changer.
Here's our costs in GA for comparison: It didn't copy the column headers but the left column is Winter, second is Summer. Not entirely sure where the switch is. Don't have a handle on what gas costs here since I haven't used it in about 15 years. $.66/Therm is what I'm seeing. So $6.60 per 1,000,000 BTU's? Not sure about that conversion.

First 650 kWh @8.81¢ per kWhFirst 650 kWh @8.81¢ per kWh
Next 350 kWh @8.16¢ per kWhNext 350 kWh @11.06¢ per kWh
Over 1000 kWh @8.06¢ per kWhOver 1000 kWh @11.66 ¢ per kWh
 
Set your location to Hagerstown, MD, and then ship it to your door. It let me go through the process and submitted the order. They haven't canceled it or changed it. If they do, I'm no worse off than before. Also, if it doesn't work and the price difference stays the same, I'll pick one up on my way home from PA when I go in a couple of months.


View attachment 93667
Just ordered, we will see what happens.
 
I worked for a company that worked on an original design of heat-pump water heaters back in the late 1970's (1978, 1979) back when the hike in gas prices had everyone thinking energy conservation. We built 150 of them (3 to be installed in every state including Hawaii, and Alaska) paid for via a DOE project. That also included 150 instrumentation packages I designed that we made that switched the units from resistive to heat pump mode 2 week in each mode repeatedly, and recorded the water temperature in and out, and KWH used for each mode on 2 separate KWH meters. A utility in each state installed them. We had a competitor that made a unit that was a box external from the existing water heater and used a water pump to circulate the water to and from the condenser. Ours was more efficient, and existing units now days are a spin-off of the design we made back then. The company was actually two companies all in one, same offices, same staff. One was not profit, and one was for profit and issued limited stock. One was called Energy Utilization Systems, and the other was called EUS.

We used R-12 back then. The refrigerant charge was very critical on those units. The maximum pressure reached right before shutting down when the water is hot enough to cause the thermostat to trip makes the compressor hard for the last part of that heating cycle. Over charge them and you really over-worked the compressor. I would imagine that the refrigerant change still has to be spot on with the units built today even with the different refrigerants now day, unless some company has included an accumulator or receiver, but the bean counters never want to add anything that cost something if it can be made to run without it.

All in all, if you live in an area where is gets hot often, these units are cheaper to run than electric resistive hot water heating, and you get some free air-conditioning, and free de-humidification.

If you put it in an area were the evaporator gets clogged from dust and or pollen keep the evaporator clean. If the evaporator gets clogged up the low side pressure gets lower, and then the pressure difference between the low and high side gets wider and the compressor has to work harder.

I have natural gas and live in a Northern state. But if I lived in the South without natural gas, I would have a heat-pump water heater in my house.
 
Here's our costs in GA for comparison: It didn't copy the column headers but the left column is Winter, second is Summer. Not entirely sure where the switch is. Don't have a handle on what gas costs here since I haven't used it in about 15 years. $.66/Therm is what I'm seeing. So $6.60 per 1,000,000 BTU's? Not sure about that conversion.

First 650 kWh @8.81¢ per kWhFirst 650 kWh @8.81¢ per kWh
Next 350 kWh @8.16¢ per kWhNext 350 kWh @11.06¢ per kWh
Over 1000 kWh @8.06¢ per kWhOver 1000 kWh @11.66 ¢ per kWh
that is not apples to apples.
take your electric bill and divide by kwh to equal true cost per kwh.

my "cost" for kwh is 5cents.. my true cost with taxes delivery connection charge etc 17cents.

All good. That’s the way to go. Did they promise you certain outlet temp?
mine you can set anywhere from 110-150f
I keep it at 140f in the winter and 130-135f in the summer.
below 120f you can get bacteria etc.

None of these are tankless so is outlet temp really the right question?
 
that is not apples to apples.
take your electric bill and divide by kwh to equal true cost per kwh.

my "cost" for kwh is 5cents.. my true cost with taxes delivery connection charge etc 17cents.
I think you can be selective to what you add. I would only add charges that change with the amount of power you use and leave out the fixed costs. What do you think it will be then?
 
that is not apples to apples.
take your electric bill and divide by kwh to equal true cost per kwh.

my "cost" for kwh is 5cents.. my true cost with taxes delivery connection charge etc 17cents.
Good point....I'm in low brain mode today...

Looks like I average about $.11 per over the year. $.10 in the winter and $.12 in the summer, give or take. This is just straight-up taking my total usage by what I paid. I think that's a fair way to look at it since that's what that service cost me.
 
Interesting concept, never heard of this style of water heater before. For an old house up north would they be good to put in a basement to keep the air dried out? Not electric, gas powered.
 
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