Dehumidifying benefits from electric heat pump h2o heater ??

Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: sperry On: Fri Oct 07, 2016 8:59 pm

Recently our electric water heater had succumb to age. Having to replace the appliance it appears that a electric heat pump water heater should be purchased to replace our old heater. I'm all in on the purchase especially with the $600 credit discount available from Efficiency Vermont program. My question is what amount of dehumidifying is the average result? Enough to replace a standard dehumidifier? Some mention a cooling effect in room also? All bonuses for a damp basement install especially when summer time will be when its used. Thanks to our ol 63 520! Anyone that been there done that I'd appreciate you sharing your results.
sperry
 
Stove/Furnace Make: efm/alaska
Stove/Furnace Model: 520/fireplace insert


Re: Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: Freddy On: Sat Oct 08, 2016 4:39 am

I work in the lower level of my house (basement). I used to have a big old, and inefficient, air conditioner in a window. It got used 20 or so days days a year when it was hot & humid. Two seasons ago I installed a heat pump water heater for summer use. It makes a HUGE difference for me. I removed the AC and have not needed it. We do AC the upstairs so that might help too, but certainly the heap pump does cool the area and remove a bunch of water. Now that it's Fall, I notice the cooling effect more. One thing: They do make a certain amount of noise. You wouldn't want one in a living area..... Ohhh, you could live with it, but most people wouldn't want the fan noise. They do run quite a bit.
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: Richard S. On: Sat Oct 08, 2016 7:18 am

sperry wrote:Some mention a cooling effect in room also?


As the name implies it "pumps" heat, they move heat from one location to another which is also what an air conditioner does. Heat pumps for houses source their heat from outside air, as the temperature drops they become less efficient.

The heat pump on hot water heater uses indoor air, the source of your heat is your primary heating source hence the reason it's going to make the room colder. This is fantastic if you live in a warm climate or during the summer and want to remove heat from that living space. The efficiency of these are based on regular electric, if they are saying it's 200% efficient it's going to use half the electric of standard. What is not included in this is the heat that it stole from primary heating source.

Let's suppose you have electric heat, you put 2000 BTU's into the air and then the heat pump uses 1000 BTU's of electric for mechanical energy to move it to the water heater for total of 3000 BTU's. I'm unclear exactly where that 1000 BTU's of energy used for the mechanical energy goes. Some of it for example will turn to heat because of friction and be put back into the room.

I have topic on that here: Pressure and AC/Heat pumps

I don't see how this can ever be as efficient as directly heating the water with 2000 BTU's in regular electric water heater. There is caveat here, you have a primary heating source that is far lower cost per BTU than electric. Even if the energy use increases the costs will probably be lower over standard electric since you are basically using coal to heat the water. Of course the dehumidifying costs you avoid should also be considered but how much does your dehumidifier run?
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

Re: Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: Rob R. On: Sat Oct 08, 2016 7:52 am

Seems like a good idea to me. For 1/2 of the year you get very economical hot water, and a cool & dry basement. For the other half of the year, if you find the basement gets too cold you can use the EFM or run the water heater in standard mode rather than heat-pump.

I am very impressed at how much moisture our heat-pump AC unit removes from the house, on a humid day it is nearly a steady stream of water from the drain tube.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy

Re: Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: Rob R. On: Sat Oct 08, 2016 12:53 pm

Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy

Re: Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: Richard S. On: Sat Oct 08, 2016 3:51 pm

Note they do have hybrid models, the recovery time on heat pump models can be fairly long which for most people shouldn't be much of an issue. They can be set to use standard electric for fast recovery or put it on full time.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

Re: Dehumidifying benefits from electric heat pump h2o heater ??

PostBy: sperry On: Fri Oct 14, 2016 8:05 pm

I just want to start out by saying what a great resource you guys make this site for all! Thanks for the follow up. Richard I did come across your post and find it interesting. As mentioned the bonus for our install is that it will only be in operation during the summer months, allowing us to benefit from the potential side effects of heat pump operation. Unplugging a dehumidifier and a little cooling effect in summer months is surley a welcome thing around here! The hybrid style is what Vermont Efficiency is offering the 600.00 instant rebates toward. So finally I had time to purchase one from our local retailer today. All in it ends up being two bills more than a conventional electric water heater. IMHO Not too bad. I’ll post the results when available.
sperry
 
Stove/Furnace Make: efm/alaska
Stove/Furnace Model: 520/fireplace insert