boiler temp issue

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smjf

New Member
Jan 14, 2017
2
?
I've been operating a wood master flex fuel 100,00 btu boiler for 3 years now. All was good until the 3 way valve started to fail. This would create the water temp in the boiler to over heat and cause the system to go into "part mode". Basically self protecting so it doesn't boil the water and explode. Ok , that's nice. But after changing the valve, the part mode has started again. Anyone had this issue and solved it ?? I'm wondering if the heat exchangers need maintenance. I flushed the boiler water when I changed the valve. Now what ? By running the 3 way valve at 90* instead of the recommended 140*, I seem the be able to get the hot water sent to the tank. Any advise will be great, thx in advance !
 
I don't have one, but looked at the manual.

From the diagram, the diverting valve has a temperature head and a sensor with wire/tube? back to the temperature head to control the return temperature. I don't know how those controls work, but maybe there's a problem with the head or wire/tube or even sensor? Not sure if you replaced them all.

Is the pump okay?

All valve lined up correctly?

Is there a trouble code?

Just brainstorming...
 
I don't have one, but looked at the manual.

From the diagram, the diverting valve has a temperature head and a sensor with wire/tube? back to the temperature head to control the return temperature. I don't know how those controls work, but maybe there's a problem with the head or wire/tube or even sensor? Not sure if you replaced them all.

Is the pump okay?

All valve lined up correctly?

Is there a trouble code?

Just brainstorming...
Thx for replying. Pumps sound like they are circulating water. Boiler water keeps getting too hot and it goes into half power. Smart computer. But why the water too hot ?
 
One of my theories was that the sensor, wire (or whatever), or temperature control head was wacky. What did you replace when you replaced the mixing valve?
 
I just had another idea. I was having the same problem when I was just now starting up my pellet boiler that had been inactive because I was using the oil boiler. Anyway, I think there was a slug of air in there, because things cleared up, for whatever reason, when I turned on a zone.

So, maybe there's air in your system.