# Complete Heat troubles



## fourcsons (Jun 12, 2012)

I have a 10 year old complete heat tied to the am 30 it was sold with.
No DHW. The am 30 can not see that the hm has hot water in it. Tech support had me change the board in the am unit. New circ pump on top of hm unit. circ pump in am unit good and works when 115v is applied. occasionally the pump in the am unit runs and life is good. Mostly the hm blows t&p and unit shuts down.

I'm thinking thermistor somewhere on hm but who can get tech support on the phone these days when we aren't both covered up.


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## moshei (Jun 21, 2012)

Ok, the reason is there is a high pressure device that can release extra pressure build up from overheat situation. And I know this is basic, but have you checked the filter? 


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