GE Geospring with an indirect

Dixmont

Hello, everyone. New to the forum and have done some reading. Hopefully I have come to the right place!

I just purchased a GE GeoSpring HPWH and want to connect it inline with my existing system. I currently have an indirect system using a 41-gallon Amtrol Boilermate. Based on my estimated hot water usage and the timing of the usage, I think the 50-Gallon GE will not keep up without bumping up the mode (less efficient).



I am wondering if there is a preferred arrangement to place the GE and use my existing Boilermate as a storage tank? I would like to shut my boiler off for the summer months if possible. I have considered simply putting the GE in line prior to the Boilermate with the hot supply from the GE going to the cold inlet of the Boilermate. This would appear to work as long as we are using hot water on a fairly frequent basis.



Is there a better option? I'm wondering about using the thermostat on the Amtrol to control a circ pump to mix the Geospring water into the Amtrol when the temperature in the Amtrol drops. I'm not sure if it will work or exactly the pump and equipment I should use. Any help, descriptions, or experiences are greatly appreciated. Thanks.

kcopp

If you have...

an indirect why buy the HPHW? I don't think you are saving any money in the short or long term....

Zman

What type?

What type of boiler is powering the indirect. What are your fuel and electric rates.

Keep in mind the geospring savings are as compared to electric. Another inconvenient fact is that the heat it "pumps" is coming from the air inside the house.

Carl

moey

buy another

I would do this instead:



http://nwwaterheaters.com/blog/featured-uses/rheem-marathon-water-heaters-booster-tanks-airgenerate-airtap-hybrid-water-heaters/



and leave the Amtrol at the street



only you know your usage, but give it a try for a month. I think you'll be surprised at the cost to operate, I suspect it will be noticeably lower then using your boiler. Unless your paying > 16c kw/hr

Jean-David Beyer

Unless your paying > 16c kw/hr

My latest bill was for $64.25 for 424 KWH. That is almost $0.16/KWH: $0.1515/KWH.

moey

probably should not have put a number in

you would need to do the math I just threw out a number, which probably should not have done

Dixmont

Answers

Kcopp - Quite certain of the savings. $999 GE unit minus $100 military discount - $300 State incentive plus install it myself. I can't get the additional $300 Federal Tax Credit because I used it on a pellet stove a couple years ago or that would have really sweetened the deal! Oil in Maine is around $3.60/gallon and power around $0.15/KWH. I track my oil consumption and use around 1 gallon per day in the off heating season. At these rates I spend $100 a month on water heating for around half of the year or around $600. Best estimates from my research is that in Hybrid mode I'll bump my electrical bill by $20-$30/month. I'm looking at about a two year pay back.



Zman - See rates above. The unit is in my basement and I am monitoring the heat change in the area. I am noticing no appreciable drop from the 58 degrees it was when I installed it last weekend. It is a walk out basement and it is used as our main entrance.



Moey - Already bought the unit, I would think that I could get my setup to do the same as what you posted, just not sure of the arrangement.

I am currently running just the GE unit in hybrid mode (would rather be in just the heat pump mode) at 130 degrees with the Amtrol bypassed and no issues with lack of water. I do want to get to just the heat pump mode, but I do think I'll need to come up with a storage option to make up for the slow recovery. Any more input is appreciated. Thanks.

kcopp

get ready....

for a cold basement.

Zman

Good info

Here is a link to the spread sheet www.eia.gov/neic/experts/heatcalc.xls

You are presently paying $44.86 per MBTU with the geospring running in non heat pump mode, $17.58 at peak efficiency.

Your boiler is costing $32.45 per MBTU on it's best day.

What do you think of putting the boiler mate before the geospring and setting the boiler mate aquastat as low as it takes to keep the geotherm in heat pump mode?

Just thinking out loud.

Carl

moey

rates

Sounds like the same deal as me. I run my pellet stove and don't use my boiler for much of anything anymore. Nice heating my 2000sq ft place on $800 a year. I just put in a electric hot water heater about a month ago my boiler was using about 30 gallons a month just for hot water.  You might check out some of the other suppliers for electrical power. Im at 13.3c in southern maine with CMP and Electricity Maine. Of course if your with one of the smaller electrical providers you can't switch suppliers.



Didnt realize you can only use the $300 federal credit only once, I used it for my pellet stove a couple years ago. I was thinking of getting the GeoSpring at Lowes when I saw Maine had the rebate I figured I could get it for about $250 when all was said and done. I guess thats not accurate. I would avoid any setup that makes the dino come on.



The heat loss calcs dont account for all the heat your boiler is losing just sitting there after it fires. Its considerable in most cases. Keep that in mind if you hook up your boiler. I suspect you would be able to run all electric and still be much cheaper then your boiler.

Dixmont

Tax Credit

I have CMP also, just using the Standard Offer. I'll look into the other offers more. I believe th tax credit has a cap, now set at $500 (I think). If you have already used that (or more), I believe you cannot claim again. I am going to research it more, but I think that is the answer.

I agree on not using the boiler if at all possible during the summer. It will be on in the winter for some supplemental heating that the pellet stove cannot handle. I am checking into a recirc pump run off the Amtrol thermostat to increase my storage and subsequently allowing to go to just the heat pump mode. If anyone has experience with that I am all ears!