I have the above mentioned heater. It will come on and heat for about 10 minutes. Then the ignition control module trips out with the led light blinking three times indicating ignition lockout. After checking all shutdown end devices and not being able to locate a problem? All voltmeter checks are good. Pentair rep sent a new contol board no charge and that changed nothing. The thermistor is new as well. I am beginning to wonder if the ICM is the problem but hate to spend that much without knowing for sure? Any assistance or other things to check would be greatly appreciated.