PB105 won't turn off

[jeffrsmith]

I have a PB105 that won't turn off, if I turn the low temp knob to "Off" the status light goes out but the feed auger continues to feed pellets at the normal interval.

Yesterday I started burning Hamers Hot Ones and noticed the pellets are much smaller, when I first started the unit with the new pellets I had a rather explosive start. When I came home from work today I noticed that I had a flashing "seven" so I pull the fuse and reset the unit. Again, when I started it up I had a rather large boom from the unit when it finally started. I have adjusted the dip switches to reduce the amount of pellets in the burn pot when starting.

I wanted to check it out to see if it would start without a bang, so I attempted to shut it down using the "Off" position of the low temp switch - like I said above the status light goes out but it still continues to feed pellets at regular interval.

Does this sound like a control board failure? Has anyone else ever experienced an issue like this? The boiler is still working ok but I can't shut it down without securing power.

 

[dmaclaren]

U may want to post in boilers or search for PB105 and PM them.

I know my PF100 has an auto and manual switch, are you in manual?

 

[jeffrsmith]

The PB105 also has an auto/manual switch - I am in auto.

 

[Delta-T]

should continue to feed for a bit while the temp lowers....did it eventually shut down?

 

[exoilburner]

My Harmon pellet furnace takes almost an hour to shut down after turning it off. It even continues to feed pellets after turning it off but it does eventually shut down.

 

[jeffrsmith]

Don't know if it finally shut down, I didn't leave it off that long - only about 15 minutes. I will try shutting if off and leave it off tomorrow when I am home to see. Again today when I got home it was flashing 7 at me - I turned the low temp knob to "off" and then back on and it cleared the flashing. I don't understand why, all the sudden, the fire is staying lit like it is in "manual" - until Sunday, when the boiler got to temp the fire would go out and then start up again when there was a call for heat. I called my dealer today about the "delayed start", manual type operation while in automatic, and my burn pot bubble/crack issue - waiting to hear back what they are going to do.

I'll let you know what the outcome is.

 

[Delta-T]

how long have you had the unit up and running? 7 blinks is overheat shutdown, are you sure it was 7 blinks? if you continue to get the 7 blinks, but the temp gauge is not registering an excessive temp you might want to look at the aquastat, or check for low water level in the boiler. if you have the "hump" in the burnpot, that could be part of the slow ignition and kaboom at startup.

 

[Skippydo]

The PF100 has a probe in the vent liner above the combustion fan. If that is dirty, it
will do some crazy things. Keep it clean, you only need to clean with a soft clean cloth.
Possible the PB105 has this same probe...
Good luck

 

[summit]

get a service guy w/ a DDM out there to give you a proper reading on the aquastat. Go from there. Whats the water draw like? if enough of a trickle, that thing can run on standby into perpetuity.

 

[jeffrsmith]

I haven't had anyone out yet, but the Hamer's that I was burning were very small and had a lot of very coarse "fines". I cleaned the unit and picked up some InstantHeat pellets from Tractor supply. These pellets burned well without causing a major overheating, but when the unit was shutting down between calls for heat it would sometimes get up to about 200-210 degrees.

The dealer that I bought the Hamer's from came and took them back, he too thought they seemed not up to par. He replaced them with Turman's pellets. I put two bags in the hopper and last night I heard banging in the pipes and an awful odor was coming from the basement. I went down and checked it out - the boiler temp was at 275 and the foam insulation was melting off the pipes - at least I know that the pressure reliefs on both my oil burner and my pellet boiler work - I had water all over my basement floor. I opened the door to the burn chamber to shut the unit down, and had to turn all the thermostats in the house way up to lower the temperature in the boilers.

I have emailed Harman and spoke to my dealer about this issue and have had no response. I called my dealer just the other day and he was surprised that I had not heard anything back from Harman. I sent them another email last night asking what they are going to do about the issues I am experiencing. Harman apparently has agreed to cover the replacement of the bubbled/cracked burn pot.

One of the biggest issues that I have is that Harman did not even acknowledge receipt of the email that I sent, nor did they contact my dealer about the email. The dealer did put in a request for installation of the new style pressure ignition system and Harman refused stating "he has not had enough problems with his unit" to warrant installation of the revised ignition system.

I was going to install the new burn pot myself, but I will probably have the repairman from my dealer replace it so he can check the aquastat and any other components he thinks could be causing the problem.

I hate having to burn oil because this pellet boiler won't play properly.

 

[jeffrsmith]

Repairman came out today and installed the pressure ignition mod and a new circuit board - time will tell if this fixes the problem.

 

[smwilliamson]

Good ole part swapping. I work on more than a 1000 stoves a year and replace about 6 control boards. I go into these dealers and look at piles of control boards they are waiting to send back for credit....shame.

Thought it may have well been a faulty board...we'll see. How much cleaning did the tech do?