Question about Pentair Minimax Ch 400,000 Btu Propane Pool Heater Millivolt Ignition

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Pool heater cycles off and on

Raypac versa, electronic .  cleaned filter and tryed by pass on pressure switch but problem persists.  Heater was neglected and full of leaves and rat droppings but that has been cleaned . Paul Minimax 400 pool heater cycles on and off about every 30 seconds? Is it the pressure switch or possibly the flow valve? Somethig else I have a similar problem on a minimax 400. I replaced the control board but that wasn't it. I bypased all limit switches and it still cycles. Manifold get's very hot, so I'm pretty sure ti has to do with the flow control valve. I removed the flow control valve last night and am lookign at it now. It there any way to tell from sight if it is bad? Otherwise, $120 to buy a new one. If I replace it and that's not it, what else can it be?

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Insert on hot water and see if open or close than on cold water and must reverse from hot. if nothing happen replace

Posted on Sep 19, 2009


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