Heat pump water heater?

[daleeper]

I've had a little mung or something get into the drain and clog it up a little. I found a little rusty colored water running down the side of the heater. I gave the hole a poke with a wire and got it cleared. Never came back after that... How did your drain break?

Well that model had trouble with the coils leaking, and we had it repaired, and I think they must have cracked it at that time, or I did, when getting it prepped for repair. The filter slot is also bugered up some. The drain connection that connects to the drain hose broke off at the bottom of the catch pan. I think I can probably make something work, but is in a real bad location to work on, so haven't taken it on yet.

 

[NSMaple1]

Here's another angle, still in testing I think but almost ready for sale maybe?

http://www.americansolartechnics.com/products/space-heat-pumps/

You could do space heating, a/c (check out the fan convectors on the site), and heat your DHW. The connections between outside & inside are regular plumbing & carry an anti-freeze - all the refrigerant stays in the outside unit. Could do as much as a mini-split, plus DHW on top of that, and you could DIY it easy without a reefer tech.

 

[stihly dan]

Late to the party here. I have had the geo spring for 5 years now. It drops my basement temp 1 to 2 degrees. My basement is not insulated here in NH, on a 0 degree night and say 10* day, my basement would be 53* with the HPWH it is 51*/52*. For 7 months of the year it is FREE hot water and I actually MAKE money. This is do to not running the dehumidifier. The other 5 months the electric bill did not go up from what it was before, AND that was with OIL heat. I run mine in the summer at 140* with a mixing valve set at 118. Basically makes it an 80 gal tank. I actually waste hot H2O in the summer because I want the dehumidification. I get rid of about 3 gallons a day dehumidifying in the summer. I save a butt load of money off this thing. Now the newer ones are at 3.5 compared to my 2.5. They don't even make an electric water heater above 55 gallons anymore. Electric is obsolete, in a few years you won't even be able to buy any above 15 gallons.

 

[Mustang71]

So ur saying in the summer it costs as much as running a dehumidifier? So soon to be a family of 4 I wonder if a mixing valve would help the efficiency a bit. I'm not buying one soon since my tank is still cooking but in a year or 2 if it'd really a good energy saver I could see it happening. You most likely have about the same weather as I do which was one of my concerns...winter efficency.

 

[JosesmicT]

Why are you thinking about switching to propane? Do you know exactly how much your electric heater is costing you?

We have an 80 gallon electric, it costs us in the area of $25/mo. Family of 5, $0.18/kwh electricity. I did put an extra layer of insulation around it, and added a heat trap to the outlet. And it's up off the floor on a stand with insulation under it. Don't think you'd find anything much more economical especially factoring in up front costs. Except for a heat pump model. They also have the added benefit of dehumidifying in summer and giving a bit of a/c effect.

How old is your tank?

$25 a month? How thick was this layer of insulation you used? Cause holy cow, you somehow made that sucker efficient! What temp is the water set to on that thing?

 

[NSMaple1]

Just a layer of fiberglass, think it's 4" thick. Held in place with Reflectix & tape.

Set to around 120.

Nothing special - electric tank heaters are more efficient than most people think.

 

[TonyM]

$25 a month at $.18/kwhr gives you about 30 gallons of hot water per day if you raise the temp 60 degrees F. That's assuming no heat loss. That's not very much hot water for a family of 5. The average US household uses something like 70 gallons of hot water every day. Let me guess, no bathtub in the house? I think my wife uses 30 gallons of hot water a day by herself.

 

[ChoppyChoppy]

[QUOTE="stihly dan, post: 6160140, member: They don't even make an electric water heater above 55 gallons anymore. Electric is obsolete, in a few years you won't even be able to buy any above 15 gallons.[/QUOTE]

That's not true. They have 80 gallon units available at Lowe's for sure, was looking at water heaters 2 days ago.

 

[ChoppyChoppy]

$25 a month at $.18/kwhr gives you about 30 gallons of hot water per day if you raise the temp 60 degrees F. That's assuming no heat loss. That's not very much hot water for a family of 5. The average US household uses something like 70 gallons of hot water every day. Let me guess, no bathtub in the house? I think my wife uses 30 gallons of hot water a day by herself.

My gas bill is $25-30. Gas water heater, dryer and kitchen stove.

Raising the water only 60* would be pretty cold water. I have mine set to 120*. Incoming is 36-38*

 

[Marshy]

... Now the newer ones are at 3.5 compared to my 2.5. ...

Tell me more... Who are the manufactures of the HPWH?

So ur saying in the summer it costs as much as running a dehumidifier? So soon to be a family of 4 I wonder if a mixing valve would help the efficiency a bit. I'm not buying one soon since my tank is still cooking but in a year or 2 if it'd really a good energy saver I could see it happening. You most likely have about the same weather as I do which was one of my concerns...winter efficency.

I have the same weather as you as I'm on the southeastern edge of lake Ontario about 2.5 hours east of you. I was told by the GE rep the heat pump is equivalent to a 400 BTU/hr air conditioner. If you look up humidifiers you will see they are sized in that range more so than a window sized air conditioner. The concept between a heat pump, air conditioner and dehumidifier is identical. Only difference isn't where the hot or cold air is going.

Don't confuse capacity with efficiency. Turning the take temperature up and using a mixing valve will increase the capacity of the tank, not the efficiency.

 

[TonyM]

My gas bill is $25-30. Gas water heater, dryer and kitchen stove.

Raising the water only 60* would be pretty cold water. I have mine set to 120*. Incoming is 36-38*

Yeah, 60 degree rise is probably about the overall temp rise for a shower, meaning 30 gallons of water per day total usage, not just hot water. My point is $25 for electric hot water per month is unreasonably low for a family of 5.

In your case, how much do you pay per MCF or gallon? Gas is usually cheaper per BTU than electricity, especially natural gas. Although there is more wasted energy with a gas water heater.

Electric elements are 100% efficient at transforming electricity to heat. So $25 per month divided by $.18 per KwH equates to 139 KwH per month to heat water (25/.18). Converted to BTU, that is 473,889 (3,412 BTU in 1 KwH). One BTU raises one pound of water 1 degree Fahrenheit. So 473,889 BTU would raise 5924 pounds of water 80 degrees F (473,889/80). A gallon of water weighs 8.3 lbs. So 5924 pounds of water is 714 gallons (5924/8.3). Over 30 days, that is just under 24 gallons per day (714/30), which is not very much hot water. In reality, some additional energy (5-10%) is lost to standby losses, so even less hot water per day is available.

By comparison, natural gas at 7$ per MCF (about 1,000,000 BTU) would cost $3.32 for 473,889 BTU of energy. Even if the gas water heater was 65% efficient, it would only increase the cost to $5.10. So natural gas is about 1/5 the cost of electric for hot water at the above energy prices (even for an inefficient gas water heater), all else being equal.

 

[TonyM]

By comparison, LP at $2.00 per gallon produces 473,889 BTU for about $10.42. At 65% efficiency, it increases to $16.02
A heat pump with a CP of 2.5 would produce 473,889 BTU on electricity at $.18/KwH for $10.00

The following produce the same quantity of hot water:

Standard electric storage water heater - $25 (@ $.18/KwH)
Hybrid electric water heater - $10 (@ $.18/KwH)
Natural gas water heater - $5.10 (@ $7 per MCF)
LP water heater - $16.02 (@ $2 per gallon)

 

[NSMaple1]

I am quite sure in my figures - unless our meter is whacked, which I seriously doubt.

No baths, showers only. I'm only in there 5 minutes - 10 at the most on cold winter days if I picked up a chill. But it's heated with wood then. Wife the same, she's usually quicker than me since she does hers before going to work. Washer usually uses cold water - odd load uses warm. Never hot. Dishwasher runs a load every 2-3 days.

Don't think I'm alone, have read of similar consumption figures elsewhere.

 

[Mustang71]

Tell me more... Who are the manufactures of the HPWH?


I have the same weather as you as I'm on the southeastern edge of lake Ontario about 2.5 hours east of you. I was told by the GE rep the heat pump is equivalent to a 400 BTU/hr air conditioner. If you look up humidifiers you will see they are sized in that range more so than a window sized air conditioner. The concept between a heat pump, air conditioner and dehumidifier is identical. Only difference isn't where the hot or cold air is going.

Don't confuse capacity with efficiency. Turning the take temperature up and using a mixing valve will increase the capacity of the tank, not the efficiency.

I'm not confusing the two but a if u took 3 showers in a row or a bath and then showers which all happens around here you are getting more capacity out of a 50 gallon tank with a mixing valve. I'm just wondering if that's more efficient than having a 75 gallon tank because you are storing 50 gallons of hot water not 75 but it's at 140 not 120 degrees.

 

[Mustang71]

I like all the energy calculations too. That's the reason I don't heat hot water with propane and if I had natural gas I wouldn't care about any of this.

 

[TonyM]

Nsmaple1, I don't doubt your usage. Just wish my family was as conservative. 2 teenage boys taking two showers per day and wife and daughter filling wirlpool tub at least once a day. Adult daughter coming over to do her families laundry. We use 250 gallons of water every day.

 

[NSMaple1]

Nsmaple1, I don't doubt your usage. Just wish my family was as conservative. 2 teenage boys taking two showers per day and wife and daughter filling wirlpool tub at least once a day. Adult daughter coming over to do her families laundry. We use 250 gallons of water every day.

If we're conservative, it's not because we're trying to be. It's just the way our things are.

Sounds like maybe our situations are flip sides of a coin - conservative vs. excessive? My sympathies for your situation.

 

[Mustang71]

I'm sorta on the other end of conservative also. I have a 2 year old and one on the way. Water usage just happens no stopping it so maybe I can help the electric bill. I'm constantly walking around and shutting stuff off lol I'm switching from cfl to led lights as they go but this water heater and dryer kill the bill

 

[Need2Saw]

Why are you thinking about switching to propane? Do you know exactly how much your electric heater is costing you?

We have an 80 gallon electric, it costs us in the area of $25/mo. Family of 5, $0.18/kwh electricity. I did put an extra layer of insulation around it, and added a heat trap to the outlet. And it's up off the floor on a stand with insulation under it. Don't think you'd find anything much more economical especially factoring in up front costs. Except for a heat pump model. They also have the added benefit of dehumidifying in summer and giving a bit of a/c effect.

How old is your tank?

Why would you have a 80 gallon water heater if your using less than 50 gallons of how water a day? My 50 gallon electric is using $50+ per month with my wife, 2 children(baths) and myself. If i turn on my recirc pump, the bill goes up $20/month. Hard to believe i could spend $20 heating recirculated hot water and you spend $25 on your total hot water bill. I wish that was possible with my .13cent/KW electric water heater.

My dad on the other hand, he has a 40 gallon natural draft natural gas water heater. He used 1.2-1.4MCF in the summer months on hot water. With his natural gas costing $6.04/MCF, he pays more for the meter charge($11.75) than he does for the gas, but he doesn't use much hot water. (2 adults)
I'm still trying to figure out how to get natural gas to my house....hmm.

 

[ChoppyChoppy]

Why would you take 2 showers a day?

I take a shower every 2-3 days in winter, every night in summer.