Steam boiler won't start (Weil McLain PEG50)

Vince1017

Please help with identifying the root cause of my heating problem

Weil McLain PEG50 (2017), Hunter thermostat. Just heat, no HVAC.

I disconnected thermostat for about a month due to construction. Today finally reconnected it but boiler wouldn't start after setting temp above room temp.

Troubleshooting steps/observations

1. Drained water/flushed water - LWCO won't lit.
2. Turned heat breaker off/on - single beep
3. Turned emergency power switch off/on - no luck
4. Electronic ignition pilot set to "On" position
5. Replaced batteries in thermostat
6. When pressing + or - button on thermostat - nothing happens/temp won't change.

Where should I be looking?

P.S. Also noticed "low battery" warning on t-stat even though put in brand new batteries. In 5 mins the message went away (not sure if it matters)

Jamie Hall

Without knowing which of about a dozen models of Hunter thermostat you have, it's a little hard to say -- but my first thought would be that the thermostat is damaged or not correctly connected. My second thought would be that something evil happened to the red and white wires (if your colour coding is standard -- it may not be). If you know what you are doing, you can try connecting the two thermostat leads at the boiler together -- the boiler should start. Do NOT connect those two leads to anything else, however. If you are unsure, don't.

But based on what you describe, I'd bet on the thermostat.

Vince1017

Jamie Hall said:

Without knowing which of about a dozen models of Hunter thermostat you have, it's a little hard to say -- but my first thought would be that the thermostat is damaged or not correctly connected. My second thought would be that something evil happened to the red and white wires (if your colour coding is standard -- it may not be). If you know what you are doing, you can try connecting the two thermostat leads at the boiler together -- the boiler should start. Do NOT connect those two leads to anything else, however. If you are unsure, don't.

But based on what you describe, I'd bet on the thermostat.

Yeah, I did directly connect the leads - no luck. But LWCO being not lit with no water in unit still a separate issue, right?

BTW, that's how the t-stat is wired (attached)

EBEBRATT-Ed

Sounds like no power to the boiler

Vince1017

EBEBRATT-Ed said:

Sounds like no power to the boiler

How do I check? Is there a fuse or a reset button?

STEAM DOCTOR

@Vince1017 While I am all in favor of homeowners do work within the scope of their abilities,  I think that you would be well served to call in a professional. Messing around with wiring can cause more problems then it solves. 

Vince1017

Issue resolved. There was a second emergency switch I didn't know about (so silly!)

ethicalpaul

EBEBRATT-Ed said:

Sounds like no power to the boiler

^^^ called it!

Vince1017

ethicalpaul said:

Sounds like no power to the boiler

^^^ called it!

Yup