Need some trouble shooting tips please - Breckwell P400 / Classic Cast

[StrangeRanger]

Hi all,
We've been running our P4000 / Classic Cast for 4-5 seasons now. I think it's model year is 2004 or 2005. It's been great until just recently.
It will burn all day and night on 1 (low). But if I turn it up at all it will shut itself down at some point. The amount of time varies and doesn't seem to matter whether I kick it up 1 or 2 notches. Sometimes it will go for 20 min and sometimes a little to a lot longer, but it will eventually kick over to shut down mode. Just like as if I had pushed the power button to shut it down.
Then it just sits there and blinks that stupid #2 light at me. That light according to the manual will come on for just about any reason. Utterly useless diagnostics code.
I've very recently completely cleaned the stove including removing both blowers and replacing their gaskets, cleaned behind the baffles, cleaned the hopper out, cleaned the exhaust pipe and gave her the leaf blower treatment. She's clean.
When it's running it burns great. But it won't stay running if I turn it up. Thankfully it's getting towards the end of the season and it's not too big a deal, but I'd really like some ideas on what to check.
Vacuum switch? High-heat thermodisc?
I don't think it's the control board simply because it runs on 1. Any ideas out there?
Thanks,
j

 

[CJ-SR4ever]

Did you clean the thermodisc? If its dirty it may be taking in-accurate readings. It it re-settable? Alot of those thermodiscs have a reset button. I would try cleaning the disc, then unplugging the stove and plugging it back in to reset the board.

 

[StrangeRanger]

Hmm... where might the thermodisc be? Is that the one on the exhaust blower?
j

 

[CJ-SR4ever]

Most likely, it should be in the owners manual. Not to familiar with that stove, but it is certainly worth trying.

 

[heat seeker]

You could temporarily jumper the vacuum switch to eliminate it as a cause. If the stove then runs OK, you've narrowed it down. Either the switch is bad (rare) or you are losing the vacuum somewhere. That's an easy and quick test, and will narrow the field down for you.

Same for the thermodisc - jumper it out, but be in constant attendance, as you will be bypassing a safety item.

 

[SmokeyTheBear]

You could do something drastic like clean the venting and the stove with a leaf blower.

Usually a #2 error is a vacuum error, anything that interferes with the stoves ability to maintain a proper pressure difference will cause that.

A dirty stove (there is more to a stove then the burn pot,firebox, and ash pan).
A dirty vent system (the termination piece in particular).
A dirty heat exchanger.
Failing gaskets.
Failing combustion blower.
A cracked, loose, or dirty vacuum line to the pressure switch.
A plugged barb that the vacuum line attaches to.