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New Home Geothermal questions

Last Post 25 Aug 2009 07:33 AM by h2otech. 11 Replies.

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bernman

New Member

Posts:11

18 Aug 2009 07:20 PM
My wife and I are looking into building a 1950 sqft ranch in Connecticut with geothermal heating and cooling. We have 2 quotes so far for similar but different systems. They are both quoting a 3.5 ton closed loop system with a desuperheater. One is a Climate Master and the other is a Florida system. One is recomending 1-525' well and the other is requiring 2-300' wells. Which is better way to go? Another question we have is that one has an electric hot water heater with a 10kw electric backup and the other a gas fired hot water heater AO Smith) with gas backup. Which system would be better and more effecient for pre-heating the hot water? We are meeting with both contractors again within the next week and we wanted to get more info and opinions before speaking with them. I have learned alot from reading the posts on this forum but still have alot to learn. Thanks in advance for any input and suggestions. Thanks Bernie

Bernie

bernman

New Member

Posts:11

18 Aug 2009 07:24 PM
I forgot to mention about that both systems will be 2-stage and 2-zones. Bernie

Bernie

engineer

Veteran Member

Posts:2749

18 Aug 2009 09:25 PM
Natural gas or propane? My instinct is to suggest staying with all electric but others may have different opinion. Relative prices of fuel options impacts this question as well.

Curt Kinder <br><br> The truth is incontrovertible. Malice may attack it, ignorance may deride it, but in the end, there it is - Winston Churchill <br><br><a href="http://www.greenersolutionsair.com">www.greenersolutionsair.com</a>

bernman

New Member

Posts:11

18 Aug 2009 10:17 PM
Propane. The only reason we are having propane at the house is for the kitchen stove and maybe an outdoor grill. We do not have NG access at our proposed location. I am thinking all electric too, but I wanted to get other opinions and pros and cons.

Bernie

Bergy

Basic Member

Posts:277

19 Aug 2009 05:48 PM
Posted By bernman on 08/18/2009 7:20 PM My wife and I are looking into building a 1950 sqft ranch in Connecticut with geothermal heating and cooling. We have 2 quotes so far for similar but different systems. They are both quoting a 3.5 ton closed loop system with a desuperheater. One is a Climate Master and the other is a Florida system. One is recomending 1-525' well and the other is requiring 2-300' wells. Which is better way to go? Another question we have is that one has an electric hot water heater with a 10kw electric backup and the other a gas fired hot water heater AO Smith) with gas backup. Which system would be better and more effecient for pre-heating the hot water? We are meeting with both contractors again within the next week and we wanted to get more info and opinions before speaking with them. I have learned alot from reading the posts on this forum but still have alot to learn. Thanks in advance for any input and suggestions. Thanks Bernie Bernie, I've not heard of doing a single DEEP well before. Our systems use one loop per ton of required heating/cooling. The desuperheater will not work with a single gas fired water heater. Two tanks, piped in series, allow the desuperheater to heat the water more efficiently. The first tank is the "buffer tank" and needs to be an electric water heater. The tank does not need to be powered, it's job is to allow the desuperheater to heat the water whenever the Geo runs. The second tank is for the final output to the home. It can be electric, or gas. A gas fired unit heat the water cheaper than an electric unit, however, some electric companies will not allow a gas heater if they provide rebates on your system. The drawing shows how to pipe the two tanks together. Bergy

bernman

New Member

Posts:11

19 Aug 2009 06:49 PM
Hi Bergy, Thanks for the diagram. I will also look into my electric company to see if they give a discounted rate if we are electric only. Thanks

Bernie

Ona

Basic Member

Posts:189

20 Aug 2009 08:21 AM
I have a single well at 450 feet and my 3 ton waterfurnace works great. Something to consider is State law. For example, in my State (New York) you would have to get a permit if you want to drill more than 500 feet.

engineer

Veteran Member

Posts:2749

20 Aug 2009 03:07 PM
Price the cost per delivered btu for the two fuel choices. Propane contains 92k btu per gallon, and electricity 3412 btu per kwh. Electric storage water heaters tend to be 90-95% efficient, not sure about the Rinnai. A standard gas fired water heater might only be 60% efficient owing to large standby losses up the central flue.

Curt Kinder <br><br> The truth is incontrovertible. Malice may attack it, ignorance may deride it, but in the end, there it is - Winston Churchill <br><br><a href="http://www.greenersolutionsair.com">www.greenersolutionsair.com</a>

bernman

New Member

Posts:11

20 Aug 2009 09:24 PM
Thanks. I will have to look in the Connecticut state laws. We will be talking again with the 2 contractors that we received bids from next week and we will be asking them more questions. I am still leaning towards the electric water heater. I still need to find out more info as to what the best well setup will be for us, 1 or 2. Bernie

Bernie

Alton

Veteran Member

Posts:2164

23 Aug 2009 11:03 AM
One thing that I really like about an electric water heater is that when I go on trips I can cut off the water to the house and flip a circuit breaker for the electric heater. However, with gas I usually just turn the thermostat down to vacation which still uses some gas and leave on the water to make sure that the gas water heater has water. So my vote is for an electric water heater so I can easily close up the house for a season.

Residential Designer & Construction Technology Consultant -- E-mail: Alton at Auburn dot Edu Use email format with @ and period . 334 826-3979

engineer

Veteran Member

Posts:2749

23 Aug 2009 08:41 PM
I do the same thing - Water and electric water heater breaker off for any overnight or longer unoccupied times.

Curt Kinder <br><br> The truth is incontrovertible. Malice may attack it, ignorance may deride it, but in the end, there it is - Winston Churchill <br><br><a href="http://www.greenersolutionsair.com">www.greenersolutionsair.com</a>

h2otech

New Member

Posts:1

25 Aug 2009 07:33 AM
We have done single well geo systems.sometimes its hard to get a large drilling rig in a small spot or we have drilled inside the foudation on vacation cottages and then they build the house.lots of time the lot size will dictate the amount of holes drilled.choose a good mechanical contractor and driller.check the consumer protection web site and better buisness web sites.get references when possible.are the installers IGSHPA certified?we do 6 inch bore holes we 1.25 inch closed loops.we do not recomend open loop due to problems with iron and ph.we have been drilling in c.t for 30+years and done 100s of geo wells.talk to the mechanical contractors and driller and ask why 1 or 2 bore holes?some places if the driller knows ledge is deep he will recmmend 1 bore hole to save you money on the drilling end.hope this help you.