David Olson
When I turn the temperature knob to start the pump there is a loud buzzing sound (when the temp of the pool water is reached on the dial) and the pump (fan, compressor etc.) doesn't turn on.  The buzzing continues until I turn the knob back down.  This also seems to activate the 5-minute delay, since the there is no buzzing if I turn the knob back up after the initial attempt.    Any ideas on what the problem might be and if it's worth fixing on a 10-year old heater?
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