Geothermal

[nizak]

Could anyone here tell me what the electrical requirements may be for a geothermal heating cooling system for a 3200sq/ft house. I am not at all familiar with this type of heating and cooling. Not looking for specific numbers, just trying to get an idea as far as adding this to the service load calculation. 20A/240 30A/240?????? Thanks.

 

[dnbob]

For the houses we have done, which would be about 2400 sq. ft., maybe a little smaller, including the basement,
we have had a 60/2 ckt for the electric emergency heat, and a 50/2 circuit for the compressor/fan. The recirc. pump runs off of the compressor circuit through a circuit board.

I believe the emergency heat strips are 10 KW.

I would think for a 3200 sq ft. house, there may be two units, each a little smaller than what we have used.

 

[augie47]

As Bob noted, in your neck of the woods, the bigger load might be the auxiliary heat associated with most geo units.
Most of the ones I see have a 20 or 30 amp geo circuit, but a 60 amp (10 kw) auxiliary heat circuit. In MI that might need to be larger.

 

[IrishRugger]

Could anyone here tell me what the electrical requirements may be for a geothermal heating cooling system for a 3200sq/ft house. I am not at all familiar with this type of heating and cooling. Not looking for specific numbers, just trying to get an idea as far as adding this to the service load calculation. 20A/240 30A/240?????? Thanks.

Okay Heres what you do I have done enough of these to give some advice.
the answer to these questions will affect your price for wiring!

1) How many water to air units are there?

2) Are there any air to air units?

3) Is there in floor heat involved with this system?

4) Is this an open loop or a closed loop system?

5) If a closed loop system how many pumps in the pump pak?

6) Are the pump pak pumps powered off the load side of the condensor? If so is there proper overcurrent protection in the unit or do you have to provide that for the pumps in the pump paks?

7) If an open loop system is there going to be a need for a pressure pump? (most cases yes)

8) If a closed loop system are there going to be valves you need to wire at the units to keep ground H2O from running thru and coroding the coils while the condesors are on stand down?

Now with those basic questions in mind in our neck of the woods it is most common to have a closed loop system . For a 3200 sq ft dwelling it seems to me that you may to calculate a load for two water to air units with each unit having a 3 ton compressor and 15 KVA for back up heat.

Ask if the HVAC guy if he has a design for the system with specific sizes for condensors and back up heat. It's not really your job to design a heating cooling system unless you are selling one, you are just hooking up power to the units and pumps.

Make sure you ask the questions I wrote above it will save you headaches later on.

If this is your first system like this don't sweat it trust me they get easier each time you do one. Just make sure you are informed.