Bill I have a couple unused valves in the valve box we were using to "blow out" the condensation once we figured out what was going on. Let them build up pressure, open the up quickly and blow out some water, close and repeat. Last time he went up there, with the pump running, no air would come out of the unused valves. Plus, it had shut down every single diffuser. It has to be frozen up somewhere before the box.

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