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I've even disconnected power thinking it had something to do with the heater pump or ozinator but the noise is still there.
I own a Caldera Niagara (2003 model) spa. I get occassional popping noises which I cannot identify. They mostly come from the front of the tub but sometimes sound as if they come from other places. If I use the tub for a half hour, I may hear the noise once or twice. Its sometimes quite loud (enough to startle you) and sounds as if something hard hit the shell. Also, its seems to happen more frequently as the weather gets cooler. I've never heard it while working outdoors and the cover on, only when the cover is removed. I've even disconnected power thinking it had something to do with the heater pump or ozinator but the noise is still there. It happens without the jets on. Neither the local dealer nor Caldera know what the problem is. Any ideas?
I think it's time to call a priest in to perform an exorcism! LOL