frozen open loop

[mike42]

I have a GSHP running in open loop using water from my well. The water discharges through a buried pipe that comes to the surface on a stream bank. When it gets very cold at nite and the HP does not run for many hours due to programmed setback, the water outlet sometimes freezes up. It is insulated and covered where it comes to the surface, but that is obviously not good enough. Is there a preferred way to make the surface breakout in cold climates?

[motoguy128]

Maybe you can use a larger pipe and increase the slope. Ice won't form if the pipe drains completely.

If the ground isn't frozen, you could dig up the end, increase the pipe diameter the last few feet and and increase the slope a few degrees.


I wonder if there's a way to cycle the well pump independently on a timer. Have maybe a 2 hour off delay and maybe a 5 minute on-delay that gets reset when the system starts up.

The other option is to use less setback. With a geothermal system, you have to be careful with set-backs. Actually unless your auxillary is disabled you should use them sparingly... and really only for comfort (some people sleep better when it chilly).

[Gross]

it sounds like you should call your installing contractor and complain. exposed discharge piping is a silly thing to do, and goes against all common sense

[mike42]

Motoguy128, I like your suggestion of the larger pipe. The discharge pipe is actually a 3/4 inch that runs inside of a 4 inch drain pipe. The smaller pipe however runs right to the end of the larger pipe. So using your reasoning, the discharge pipe should probably be shortened to keep it further underground, and the drain pipe slope should be verified for drainage. I also discovered that the 4 inch pipe was venting outside air to the building interior which must have contributed to the freeze up. It is now sealed.