Lopi Berkshire

[Dieseltruck15]

Hello!
I have an older model Lopi Berkshire that is giving me issues. With the pilot on, once the thermostat calls for heat, the burner ignites. It burns great for awhile but eventually the burn and the pilot shut off. Usually it doesn’t meet the temp the thermostat is calling for before they both shut off. I can’t tell which is shutting down first because I’ve never actually been watching the pilot when it happens. Sometimes it runs for over an hour (when I haven’t been home all day and set the thermostat high to warm the house up) before it kicks out. So I was wondering if you can point me in what direction to look and tests I can run to rule certain things out.

Thanks!

 

[DAKSY]

You will need a multimeter set to volts DC
& take readings on the thermopile & thermocouple
Do you have one?

 

[Dieseltruck15]

Yeah, I’ve got a multimeter. What should the readings be for each?

Thanks!

 

[Dieseltruck15]

With just the pilot on the thermocouple had around 500-485 volts, it seemed to keep dropping as the pilot stayed lit longer. When I turned the stove on, the thermocouple volts dropped to around 85-78 volts. With the stove on, the thermopile was around 235-220 volts. That seems like quite the range difference to me...what do you think?

 

[Dieseltruck15]

After the stove has been on for 15 minutes or so, I rechecked the readings. The thermocouple is at 57 volts and the thermopile is at 231.

 

[DAKSY]

With just the pilot on the thermocouple had around 500-485 volts, it seemed to keep dropping as the pilot stayed lit longer.

Where did you take THAT reading. TCs generate 28 - 31 mV DC

When I turned the stove on, the thermocouple volts dropped to around 85-78 volts.

See above

With the stove on, the thermopile was around 235-220 volts.

That is adequate. Doe it hold steady?

That seems like quite the range difference to me...what do you think?

 

[Dieseltruck15]

That’s my fault, I’m sorry. I tested it completely wrong...I’ll have to retest it tomorrow and get back to you.

The thermopile I checked a few different time while it was running. It always seemed to be around 220-230. What’s the lowest that reading should drop to?

When I was doing this, I just used the switch on the stove (not the thermostat) and it stayed running for quite awhile and never shut down. I ended up shutting the switch off and when I did the pilot stayed lit as it should. I’m pretty sure I have used the switch on the back of the stove before and had it shut down after a little while of running but I usually only use the thermostat so I’m not 100% certain. Is there something that would cause the burner and pilot to shut off if I was just using the thermostat? As I said, my issue is the stove will kick on when called for heat, run for awhile but before it reaches its set point temp, it shuts the burner and pilot off.

Thank you for your help and sorry about the mis-reading on the thermocouple!

 

[DAKSY]

Take the wires off the thermostat - if it IS wired.
Touch the two wires together & tape or wirenut them together.
If it stays on, then the thermostat may be the culprit.
Let us know...