I have a MasterSpa LS700. 3 pumps and a blower. A couple of weeks ago I noticed the blower button wasn't working when I pushed it and the temperature had dropped from 100 degrees to 80 degrees overnight although I had set it to maintain temp at 100. The only way I could get it to heat back up was to manually push Pump 1 and Pump 2 button on the control pad twice for high speed every 30 minutes. Once it reached 100 degrees again, the temp would start falling again although the pumps automatically kicked in on low speed every hour on the hour. After inspecting the pumps, we found that the circulation pump was too hot to touch. I had it checked out at a local shop and they said the pump was bad. Would the circulation pump cause the problems I've described?

I've located the pressure switch, which is behind the heater. I haven't been able to test it, but I'm suspecting that it may be bad.

Thanks for any input.

Genny

Certainly it would. Usually the circulation pump is the only pump that heats the tub, through your heater.

What you were doing was using the heat and friction generated by your jet pumps on high speed to heat your tub indirectly.