Hybrid Water Heater
 

I decided to go ahead and get a hybrid water and install it before the tax rebate (30%) runs out at the end of this year.

I went with the Rheem from Home Depot.Rheem EcoSense 50 gal. Hybrid Electric Water Heater with Heat Pump technology - HP50ES at The Home Depot

I ordered it online and they delivered it to my house for free. It took about 5 days to get here. According to the EPA sticker it only uses $284 worth of electricity per year, which is about half the average. So payback should be about 4 years (after the tax rebate). That beats the heck out of anything I could do with a wind turbine or solar PV.

I had also looked at the GE offering from Lowes, but decided against it because it requires 7" of space behind it and I just don't have that kind of room to install it. Shop GE 50-Gallon GeoSpring™ Hybrid Water Heater at Lowes.com

The GE does have a better Coefficient Of Performance (2.35) than the Rheem (2.0). Also, the Rheem has unconventional water pipe connections that will require me to redo some of the plumbing. But the GE requires more space overhead to remove the air filter.

So now my garage will be cooler in the summer (good) and colder in the winter (bad). But I don't do much in the garage in the winter time.

interesting, I've never heard of a hybrid HW setup before. They aren't in the local home depot or rona at least. My electric tank is effectively silent but my heat pump is anything but. How does one of these compare noise wise?

I'm not sure on the noise. The static displays in the stores here weren't hooked up so they were silent. I haven't hooked mine up yet, but plan to in the next few days. I'll report back. My current electric element heater is silent though, so I would imagine there will be some increase in noise from the new unit.

Very interesting. I know a few forum members have looked into these and will be interested to hear your results with it!

I got it hooked up. It does make some noise when the compressor is running. It's louder than my refrigerator, but quieter than my central air conditioner. It has a circulation pump that's almost silent when it is running. Since the heater is in my garage, I can't hear it at all when I'm in the house. If it were mounted in an alcove inside a home you might be able to hear it, but if the alcove had a door on it I doubt you would notice it. The unit is really quite sophisticated - it has computer controls to maximize energy efficiency and protect the compressor. I'll try to take some pictures and post them up later today.

PS - I was amazed at how small the power wires were inside the unit. I'd say they were maybe 18 gauge, 16 gauge at the most. Way smaller than the wires in the old heater.

Here are some pix of the heater.

I find it interesting that it uses R-410a even in a high temperature application.

What does the "energy saver" mode do?

Where is its cold sink, and does this thing blow out cold air?

Energy Saver just uses the heat pump. Normal uses the heat pump with resistive heating element backup.

The heat source is the air in the garage. It blows out cold air and transfers the heat from the air into the water in the tank.

Here are some more pics:

What is the typical BTU output of your water heater?
 

Patric,

Do you have any information on what the typical BTU output of your water heater is?

Regards,

-AC_Hacker

No, just that it uses 6.46 amps @ 220V and has a COP of 2.0. That would be 1412W. If it ran for an hour that would be 1.412 kWh X 2 COP = 2.814 kWh of heat produced. If there are 3412 BTU in one kWh, that would be 9698 BTU/hr.

At 4.2kJ/kg*°C, and given a 40°C deltaT, 2.8KWh/hr (:rolleyes:) would be 60kg/hr of hot water, or about 15gal. But that's probably not right. I'm guessing the vast majority of the 6.46A is at a COP of 1, i.e. the resistive heating element.

Does it have a "first hour" rating?

Edit: I just thought of something. Does "normal" mode mean it uses the resistive heater every time you take a shower? Unless it has a frugal, intelligent controller, that mode would reduce your COP to maybe 1.2 all the time.

67 gallons.

thanks...
 

Patrick,

Thanks, just what I was looking for.

Under certain low-demand circumstances, a unit like yours could possibly be used for home heating.

As I was thinking through this, the tank would best left inside the heated space, so that heat leakage could be utilized. But the heat pump part, at least the evaporator coil, the part that gets cold, would be best left outside the heated space.

It's not so easy to find a smallish ASHP that heats water instead of air. Xringer found a small pool heater that could possibly be used.

Regards,

-AC_Hacker

Well I guess you could build some kind of a box around the coil at the top of the heater to direct the cold air somewhere else.

If you're serious about doing something like this, take a look at the GE model available through Lowes. It has a COP of 2.35. I didn't use it because it requires 7 inches of space behind it and the Rheem needs only 2 inches so the Rheem fit better where I needed to put it.

Patrick,

Thanks for the information, I'm still thinking about this... every day.

BUT... There's a thread where various water-heater options were being discussed, and since I've been using one for maybe 15 years, I put in my 2 cents worth about tankless water heaters, and I also voiced my one hesitation regarding the ASHP water heaters:

...and today I came across this illustration over at Build It Solar which more than completely addressed my hesitation...


... the picture tells the water heater story, but the whole story is well worth checking out.

Regards,

-AC_HAcker

Lowes has it on sale, today only, for $1399: Shop GE 50-Gallon GeoSpring^TM Hybrid Water Heater at Lowes.com

Maybe you could shoot the exhaust into a cold food storage closet :)

Hey everyone,
I'm new to this forum, however I bought the ge hybrid water heater back in Jan. When I moved to my new place which is out in the country I knew nothing of propane or it's costs. After 3 months and a 1200$ propane refill I knew something had to change. So I went looking in the garage to see where my propane was going. And what I found was 2 water heaters. One said it uses 276 gallons a year and the other 270. So at the price I was paying for propane at the time (3.14$/gal) that's around $1100. So I started researching energy efficient heaters. Anyways I found the ge and knew it was what I needed. So went online to lowes but no luck there. Went down to the local store and no body there knew anything about it or even what a heat pump was. So I called lowes national and talk with there rep, who then contacted the local manager who then was very helpful. They did finally get me one but had to ship it from the east coast out here to California. I will say the thing looked cool. We were getting our pictures taken next to it when I opened the carton. Luckly while I was waiting for it to arrived I ran a new 30amp line to it's future home. So when it arrived I took the day off to install it. I had to cut and piece together the copper overpressure discharge line. Also had to tee into that line to run the condensation tube too. So all that was left was to lift it into place. Damn that is heavy 2 or 3 person job. The original was light comparatively. Right after I installed it I replaced all 136 light bulbs in the house with cfl's so at the next bill it had still gone down from previous months. When running on just HP mode it draws 450watts. But when put on high demand mode when we had a bunch of guests it pulls around 6500. It is kind of noisy, like a window ac. But I can't hear it in the house. And if I'm working in the garage I can just hit the fan off button and it's nearly silent. Anyways that's been my experience. Wonderful unit no complaints..

Hv23t

136 light bulbs in the house? How is that possible? A quick count in my head puts me at 30 for a 2400 sqft house...

That's funny that's the same thing I was thinking when I was making a list of the bulbs I needed. There is 21 bulbs in my bedroom/bathroom alone. House is fairly large, lots of patio around the house with lights too.

I've got 71 at my place.

39 not counting Christmas lights. My total includes exactly 1 incandescent that requires a laddder and a screwdriver to change. It's been on for about an hour in the past year.

Have you guys ever seen the AirTap? It is an add on unit, I bought one this fall and was waiting unit spring to put it on and give it a try, I like the idea of venting the cold air from it into a cold storage area, that is a great idea...

Yes, I have heard of those and thought about getting one but didn't because Consumer Reports said you have to change the anode rod every year and I didn't like the fact that AirTap says to turn off the regular heating elements so you have no backup.

If you live in the U.S. you might want to look into hooking your unit up in the next week - I think it qualifies for the 30% income tax credit, but only if it's put in service in 2010.

I seen that their web site also sells a refillable anode rod..
they must recommend that you change it every year so that in a worst case situation you don't corrode the copper tubing you run down into the heater.
I would think that you would be able to just turn down your thermostat on your water heater to just below the working temp of this unit so that it can act as a back up..

As for the tax credit not to excited about it, not sure if it would amount to much.
unit was fairly reasonable want to say like $600 without shipping.

Well $180 is not too shabby in my book. :confused:

I know I'm late to the party, but there's 11 bulbs in my house (2 in appliances) and 4 in the garage. That's 3 incandescents, 2 linear fluorescents, and 10 CFLs, for roughly $25 in lighting. It's all staying here when I move out.

You didn't save the old incandescents so you can switch them back?

When I moved I thought about switching out my CFL's since I had the old bulbs but decided karma for helping out the world was worth more then the $40 the bulbs where worth. All I did do was take the giant 23 watt cfl's from the shop and replace them with some 13 watt bulbs. the Real big/bright ones are hard to find around here sometimes. The second or 3rd day I lived here I went shopping and bought door stops and $100 worth of CFL's including 6 dimming floods for pot lights and 2 dimming regular ones.

In 1.5 years I think I've replaced 3 of them, one was noisy from day one and works but I got annoyed at it, one I broke when I hit it while on a ladder and the other burnt out within the first month.

I have a CFL box with about 8 incandescents in it, but I should probably just throw them out.

When my last roommate and I parted ways, I left all the CFLs with her, because she's too frugal (:rolleyes:) to buy them for herself.

If you're looking for ways to spend money to save energy, giving people CFLs that they will actually use provides absolutely enormous bang for the buck.

So Patrick, have you had any problems with your water heater yet? I'm seeing on sears.com people complaining of issues and the local plumber said he had people complaining also. Just wondering how your experience has turned out so far. My local electric company gives us a $300 rebate so I've been considering this seriously.

What complaints are there?

No problems so far. My wife complained that the water temp was getting lower at the end of her shower when I had the heat setting at the lowest level. But she likes to take REALLY hot showers. I just turned the heater up a notch and it's been fine since.

The one Sears sells is the GE unit, mine is the Rheem.

Daox, Someone on sears.com said their compressor exploded after they had a brown out. That's a weird one. There were a few other people saying that it died after a month or two of operation. The plumber I called up said he had issues diagnosing problems with them. That's probably an obvious one though. You'd probably have better luck calling up an HVAC repair man.