GSHP backup heat?

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Does anybody know how to get rid of the backup heating when using GSHP's in Trace? I know for a fact that I will not have backup heat (buildings have already been in operation). However, I can't seem to get rid of the backup heat consumption. Any ideas?

hansolo's picture
Joined: 2010-07-22
Reputation: 0

Mr. Solo-

You are going to be "flying solo" forever if you don't keep your ship warm. With the way the princess dresses, you're gonna need backup heat. Perhaps that is why you partner with a self insulated wookie? In any case, this is a common problem, and is a bit more complex in nature than it may seem. Trace doesn't provide a "real" ground loop so your design knowledge and confidence that you do not need backup heat is key. The sure fire way to get rid of the backup heat is to edit the GSHP plant (in the cooling equipment library) copy it, and change the minimum operating temperature to something below 30 degrees F (you are probably using glycol anyway). The lowest you can take this number is to 0, but that will likely eliminate your heating, provided you have adequate thermal storage capacity (under the create plants, cooling equipment tab).


If you still have backup heating, you may want to doublecheck:


-Your assumption

-Your building loads (maybe not enough internal loads, solar heat gain, thermal mass, etc)

- The heat rejection method (to the ground loop)


If that doesn't work, and that would be pretty unlikely since Trace assumes an infinite ground loop, you may want to take advantage of the new(er) feature in Trace that allows you to enter custom ground loops (under create plants, cooling equipment, controls, advanced controls-  you may want to look into the manual for more help there, but I'm doubting it will ever go to this point).

Bob's picture
Joined: 2010-06-30
Reputation: 275