Wood boiler a bit flakey.

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

Bigfoot1044

New Member
Oct 3, 2020
5
Whitney, ON
I have a Heat Master MF5000e wood boiler and had an issue with it recently. The controller was hitting its low set point, which should engage the fan and open the baffle. But neither was happening. I called the dealer and he agreed to come up and take a look at it, a 3 hour drive for him. But the morning he was supposed to come up I tried turning on the boiler and behold!! The baffle made a clicking noise, and then opened and closed 4 times. Then it opened and the fan kicked in. It wasn't working for a week and now it is working perfectly. I thought the fact the solenoid was not engaging was not allowing the fan to turn on. But the dealer says they work independently of each other and the fan should come on even if the solenoid does not engage. Any thoughts on the issue would be appreciated.
 
Sounds to me like a loose connection somewhere. Or a bad temp controller.
The power from the control goes to the solenoid, then jumpers to the fan (maybe vice versa, but one doesn't control the other).
So if they both stop I test voltage at the control etc further back.
 
Sounds to me like a loose connection somewhere. Or a bad temp controller.
The power from the control goes to the solenoid, then jumpers to the fan (maybe vice versa, but one doesn't control the other).
So if they both stop I test voltage at the control etc further back.
Thanks for response. I was testing voltages as you said and disconnected the wires on the high limit switch to make testing easier. After reconnecting I turned on the furnace switch and everything started up and so far appears to be running as normal. Before the fan and solenoid were kicking on and off every second or so. So may have been one of the connections on the high limit switch was not connecting properly, possibly something in there causing a short. Hope it keeps working now.
 
Glad you found it. The high limit isn't expensive if you need to replace it.
Or maybe it needs some new connectors crimped on.
 
Glad you found it. The high limit isn't expensive if you need to replace it.
Or maybe it needs some new connectors crimped on.
Problem finally turned out to be the controller. Power was going in, but no power coming out when turned on. Dealer shipped me a new one and I managed to install it myself. (I am one of those guys who knows just enough about electricity to get myself in trouble). Working fine now. Unfortunately warranty is only one year on the controller. Those things really should last longer than 5 years I have had it. (Ranco controller)
 
Problem finally turned out to be the controller. Power was going in, but no power coming out when turned on. Dealer shipped me a new one and I managed to install it myself. (I am one of those guys who knows just enough about electricity to get myself in trouble). Working fine now. Unfortunately warranty is only one year on the controller. Those things really should last longer than 5 years I have had it. (Ranco controller)
I keep one on the shelf. $89 and nothing lasts. You should have spare solenoids on the shelf also.
 
I keep one on the shelf. $89 and nothing lasts. You should have spare solenoids on the shelf also.
Yes the solenoid that came with this one was bad. It didn't die, but was sticking open the first year. They sent me a new one no charge and then I bought a spare. Might get a spare controller too.
 
Yes the solenoid that came with this one was bad. It didn't die, but was sticking open the first year. They sent me a new one no charge and then I bought a spare. Might get a spare controller too.
Make sure you lube the solenoids with some silicon or other lube that doesn’t attract dust and crap. I hit mine at the beginning and end of the season.