As you may know, in the Albany area of New York we are without power.  It's been a day and a half and while the electric company thought it would be up and running by tonight, they are now saying that it may not be until Monday. 

With extremely cold weather our walkout basement where the geo unit sits is now at 40 degrees F (the house is at 51).  I understand that the closed loop going through the system has methanol so I don't need to worry about freezing, but I was wondering if there was anything that I needed to worry about with the desuperheater portion of this system? 

We have a thermometer in the basement and if it gets to 35 we are planning on draining our water lines, but am still unsure if there is something special that I would need to do with the geo system?  I'm probably being paranoid, but still wanted to put the question out there.

Thanks in advance for any input. 

Ona,

Sorry to hear that you are with out heat. The water in the desuperheater coil could freeze and burst the coil if the temps get much below 32.

Good luck and hope you heat soon.

Ona, if the geo unit is in the basement that will probably the last place in the house to freeze. If you have a gas water heater, fill the tubs with hot water. Hope they get your power back up, although it looks like this freezing rain we are getting might hit you guys Monday.

I agree - flowing water is your best defense.

It might take weeks for an insulated storage water heater to freeze but the skinny desuper lines and heat exchanger are a concern.

If, as in my system one side of the desuper is plumbed into the boiler drain of your water heater or preheat tank, you may be in luck - here's why - opening the tank drain wide would depressurize that line so as to draw water through the desuper.

If yours is so plumbed attach a hose and open the drain valve fully for a minute or so, exchanging the water in the desuper. Lay hands on line from desuper and feel for temperature change confirming water flow. Do that every couple hours or so and you should be OK.

Consider also taping up windows and doors in the walkout basement to cut infiltration as much as possible for the duration.

I checked NWS - low of 12 tonight in Albany, but after that you are in the clear - nothing worse than low 20s. I'm cautiously optimistic that 12 for one night shouldn't freeze lines in a relatively tight house.

Good luck.

Thanks for all your replies. Our basement weathered beautifully... it went as low as 37, but nothing froze. The workers who were fixing the downed high voltage line on that back of our property were kind enough to leave their generator running just outside of our garage last night so we hooked up two electric heaters, one in the basement and one in the bedroom. So, this brought the basement up into the 40's! Also, the geo system is in the back corner of the walkout basement which is the warmest corner (i.e. furthest from the 40 year old garage door), so it was in the mid 40's in that location.

We had considered the running water, but since we have an electric pump in our well I didn't think we could do that. We also were prepared to drain all the water lines if it hit 35. In the 6 years that we've lived here we've never had our power off for more than a few hours, so we were definitely not prepared.