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John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma

Hybrid-electric water heaters

I'm relocating to Florida. The house I am in the process of buying has two conventional electric water heaters (because it's a large single story with two different "wings"). One unit is 27 years-old, the other 9 years-old.

I am looking to replace both, for obvious reasons and am interested in the new hybrid-electric units and wondering if anyone has any feedback.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...

TheMG
Premium
join:2007-09-04
Canada
kudos:3
You need to be more specific. Hybrid what?

Gas-electric? Solar-electric? Heat-pump-electric?


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma
said by TheMG:

You need to be more specific. Hybrid what?

Gas-electric? Solar-electric? Heat-pump-electric?

Heat-pump-electric.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...


BillRoland
Premium
join:2001-01-21
Ocala, FL
kudos:3
reply to John97
I too am interested in this.

Zach1
Premium
join:2006-11-26
NW Minnesota
reply to John97
In a warm climate, like Florida, where you'll probably be cooling nearly year-round, I can't imagine, aside from unit reliability, why the ROI wouldn't be quick and post ROI savings significant. The only downside I can think of immediately is if your heaters are in the living space. A hybrid heater will probably make more noise. Also, the unit on display at the local supply house requires a condensate drain or pump if gravity drainage isn't practical. This must be separate from the T&P drain.

Be sure to let us know how it works out if you go hybrid. They look interesting but the numbers don't seem to work out too well up here where heating is primary.
--
Zach


Ken
Premium,MVM
join:2003-06-16
Markle, IN
reply to John97
I looked into them. They are really good if you have them setting in a warm area. However the heat pump mode only operates at a very slow recharge rate. If you take a shower in the morning and then leave the house for the day, you are good to go. If the family wants to take 4 showers in the morning then the heat pump can't keep up and it goes back to heating with the normal way. It will then use the heat pump to maintain heat. So depending on the makeup of your family and what your usage is the heat pump can be a huge savings, or almost no savings at all.


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma
reply to Zach1
Thanks for the replies.

Like I indicated in the original post, my new house has two water heaters which I plan to replace with hybrid units. One services the master suite, a full hall bath, and a powder room. The other services the kitchen, and two other full baths.

So, the "load" is going to be pretty evenly spread across the two units. One unit is located in the laundry room, the other is located in a utility room that is only accessible from the outside of the house. Providing a condensate drain will not be an issue at either location.

I am looking at this unit in particular:

»products.geappliances.com/ApplPr···50DEEDSR
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...

Mr Matt

join:2008-01-29
Eustis, FL
kudos:1
Reviews:
·Millenicom
·Embarq Now Centu..
·Comcast
·CenturyLink

1 recommendation

reply to John97
Here is what I learned about Hybrid-electric water heaters when I was considering one for this house:

Here is the advantage.

1) Reduces the cost of producing hot water.

Here is the disadvantage:

1) Slow recovery rate.
2) Makes noise.
3) Requires good air flow to unit.
4) Time required to pay back higher cost of unit may exceed useful life of unit.
5) Cost to repair refrigeration section is very high once the warranty expires.
6) Not enough heat absorbed to cool of a 3 car garage.

Do not waste your time with the above, get a Desuperheater.

Here is one:

»www.hotspotenergy.com/residentia···heaters/

Here is another:

»heatexchangers.doucetteindustrie···rheaters

These units recover heat from the hot refrigerant output of the AC compressor and transfer it to the hot water heater. They consist of a heat exchanger, thermostat and circulating pump. The circulating pump runs whenever the AC is running until the water returning from the water heater reaches the set temperature and then the thermostat shuts the pump off. The thermostats on the heating elements are set lower than the thermostat on the heat recovery unit so that you will always have hot water. When I lived in South Florida I had one. From about April 1 until November 1 I almost never paid to heat hot water in the summer. One summer it turned off the circuit breaker to the water heater from June until I was unable to get how water in October because the outside temperature dropped.

You will get the best results if the AC Condenser is close to the heat exchanger and water heater. Some AC manufactures are offering condensers with built in heat recovery systems. You might consider one of them if you are replacing the Air Conditioners.


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma
The house has two very new heat pumps, so I won't be replacing them any time soon. Also, the condensers are quite far from both water heater locations. So, I am not sure how well that would work.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...

Mr Matt

join:2008-01-29
Eustis, FL
kudos:1
Reviews:
·Millenicom
·Embarq Now Centu..
·Comcast
·CenturyLink
In my case the Desuperheater was installed right next to the condenser. The hot water inlet and outlet lines were insulated and ran about 100 feet to the water heater. The circulating pump is incorporated in the Desuperheater cabinet. An insulated hot gas line is run directly from the output of the compressor to the Desuperheater and then run to the condenser coil. If the water line is properly insulated the heat loss is insignificant. I owned the house for 18 Years and never had a problem with the Desuperheater. I had to replace the water heater after about the 14th year.

guppy_fish
Premium
join:2003-12-09
Lakeland, FL
kudos:3
Reviews:
·Verizon FiOS
reply to John97
In Florida the Electric tanks are usually in the Garage, so its a double benifts using the heat-pump hot water tanks as it reduces the heat load from a hot garage as when the HW runs its cools the space its in.

Also a Desuperheater doesn't work well, if at all with new high efficiency AC's as by design, they have less available heat to harvest, and the costs of a Desuperheater with installation is probably double the cost of a store bought heatpump HW unit.

An in the winter months a Desuperheater does nothing, zero payback where a Heat pump still has significant savings over resistive heating

Zach1
Premium
join:2006-11-26
NW Minnesota

2 recommendations

reply to John97
Found this bit testing for the GE hybrid heater.

»www.bpa.gov/energy/n/emerging_te···ev2a.pdf
--
Zach


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma
said by Zach1:

Found this bit testing for the GE hybrid heater.

»www.bpa.gov/energy/n/emerging_te···ev2a.pdf

Nice find.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...


Ken
Premium,MVM
join:2003-06-16
Markle, IN
reply to Zach1
quote:
The GeoSpring HPWH is marketed and sold as having 50 gallon capacity but careful
measurements showed the unit in the lab held 45.5 gallons. National guidelines on the sizing of
equipment allow a 10% variation in nominal versus actual size. This water heater fits within
those guidelines albeit on the lower end. It should be noted that the difference in nominal size vs
actual size is not unique to HPWHs and occurs with traditional electric resistance tanks as well.

I did not know that my 50 gallon electric water heater might only be 45 gallons.

ncbill
Premium
join:2007-01-23
Winston Salem, NC
Reviews:
·AT&T Southeast
reply to John97
The first-generation Geospring units have their heat pump units sourced from China, with frankly terrible reviews for reliability.

Even for those still under warranty some customers have had to wait nearly a month for parts to become available - can you live w/o hot water for several weeks?

The second-generation are now made in the U.S., but there is not yet enough data to determine their reliability - buy the extended warranty (parts & labor)

There are other heat pump-assisted water heaters out there, but they normally cost at least 2x that of the Geospring.

Why not solar instead? You are in Florida.

Or simply add a timer to each water heater?

said by John97:

Thanks for the replies.

Like I indicated in the original post, my new house has two water heaters which I plan to replace with hybrid units. One services the master suite, a full hall bath, and a powder room. The other services the kitchen, and two other full baths.

So, the "load" is going to be pretty evenly spread across the two units. One unit is located in the laundry room, the other is located in a utility room that is only accessible from the outside of the house. Providing a condensate drain will not be an issue at either location.

I am looking at this unit in particular:

»products.geappliances.com/ApplPr···50DEEDSR


HarryH3
Premium
join:2005-02-21
kudos:3
Reviews:
·Suddenlink

1 recommendation

ncbill's post brings up an excellent point. A standard water heater is quite possibly the simplest appliance in a home. I just can't see a good reason to replace one with a device that adds an electric motor, a compressor, a control board, condensor and evaporator coils and refrigerant. Just seems to be adding far too many potential points of failure. Once that thing is out of warranty any repair costs are likely to be crazy expensive.

Who do you call when it breaks? I'm fairly sure that you won't find many plumbers with HVAC skills and licenses.


ArgMeMatey

join:2001-08-09
Milwaukee, WI
kudos:2
Reviews:
·voip.ms
·AT&T Midwest
·Time Warner Cable
reply to ncbill
said by ncbill:

Why not solar instead?

If I lived in Florida and had the choice between these units and solar, why wouldn't I choose solar?

In fact it seems any residential dwelling where there would be enough waste heat to make the compressor units cost-effective, solar would be simpler choice with lower operating cost.

The report did a good job exploring the usage patterns where these would not make sense. I wondered, if I could have a larger compressor and a 100- or 150-gallon tank, could I get a better payback, or just a more realistic recovery rate?
--
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16TDN2870
Find your USNG coordinates:
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guppy_fish
Premium
join:2003-12-09
Lakeland, FL
kudos:3
Reviews:
·Verizon FiOS
reply to ncbill
said by ncbill:

Why not solar instead? You are in Florida.

I have had solar hot water, when it functions, its great, when something goes wrong it can be significant damage or have a significant cost to repair.

I've had a collect fail and once freeze ( yup even in Florida ) due to the controller being issue.

Putting holes in your roof for both mounting and larger ones for pluming, can lead to a path for water damage , a failed panel can dump a large amount of water into ones ceiling

My personal choice, having done the solar route, is cheap and simple, the cost savings for me would take decades to even break even on a Geo unit or solar.

A 30 dollar extra insulation blanket is the best solution for cost savings in Florida, the thermal losses on conventional HW tanks are pretty low as 3/4 of the year its warm and hot!, our electric rate are very reasonable as well.

scooper

join:2000-07-11
Youngsville, NC
kudos:2
reply to John97
I'm not so sure that a waterheater blanket actually buys you something tangible, with newer units anyway. Heat loss is almost zero. I have my electric tank sitting in a "waterheater enclosure" and it's been fine.
»myaquahut.com/


tschmidt
Premium,MVM
join:2000-11-12
Milford, NH
kudos:9
Reviews:
·G4 Communications
·Fairpoint Commun..
·Hollis Hosting
reply to John97
Interesting thread - here in cold New England I supplement our electric water heater with a heat exchanger in our wood stove and in the summer a simple batch heater in our greenhouse. Low tech but cost effective.

I have no direct experience with HVAC heat recovery but I would think using the waste heat from an air conditioner in a hot climate like Florida is a great way to get cheap hot water water and improve AC efficiency.

I replaced our electric water heater a couple of years ago and looked at the hybrid units. As has been posted it adds an awful lot of complexity for modest gain.

You said the HVAC is a long way from the water heater. One way to address that issue is to locate a preheat tank near the AC compressor and then plumb warm water from that tank into a conventional water heater.

/tom


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma
reply to John97
Thanks again for all the replies.

After looking over everything, I am still considering going with two of the GE hybrid units. Lowes sells an extended warranty, and I'll go with it to cover any potential repair issues. Since there are two units, even if one dies I won't be completely without hot water...

Since both existing units are in rooms that are adjacent to the garage, I am looking at the feasibility of installing the new units in the garage. The supplemental cooling effect from the two units should cool the garage down nicely. Also, it will be no problem setting up the condensate drains as well to go right out to the flower beds out front.

Putting them in the garage will also free up space in the rooms the existing water heaters are located. This will make my wife happy as she wants to put some kind of shelves/cabinets in the laundry room
It will make me happy because I'll be able to store more stuff in the outside storage room where the 2nd water heater is currently located.

Also, if one of them blows out and starts leaking water the damage will be zero in the garage with block walls and a concrete floor. I once had a water heater spring a leak up top that sprayed right into the drywall behind the unit. The fact that it was sitting in a pan meant nothing. The pinhole leak sprayed the wall like a urine stream and ran down onto the floor. I had to replace a mess of soaked drywall.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...


toby
Troy Mcclure

join:2001-11-13
Portland, OR
I have had a GE heat pump water for a few years now, I use it in the mixed mode. So most of the time it operates in heat pump mode, but when there is a high water demand it switches to regular resistive heat mode. The unit beeps to remind you to clean the air filter.

Why do you need two of them?
Remember that you'll need a drain line, as it also acts as a dehumidifier and an AC unit.


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House
·ooma
said by toby:

I have had a GE heat pump water for a few years now, I use it in the mixed mode. So most of the time it operates in heat pump mode, but when there is a high water demand it switches to regular resistive heat mode. The unit beeps to remind you to clean the air filter.

Why do you need two of them?
Remember that you'll need a drain line, as it also acts as a dehumidifier and an AC unit.

The house has two water heaters now due to the design and layout. Both need to be replaced.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...