Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Boiler won’t ignite on cold night

petermatheson
petermatheson Member Posts: 6
Over the past few days the temp in my city (and basement) dropped from 30's to negative temps, and my 2004 'New Yorker' Boiler (Classic CG-A series gas boiler, electric ignition, no zones, 4 hot-water radiators) has started to sometimes not ignite. It typically happens in the middle of the night: the newish Nest thermostat calls for heat, the boiler's water pump starts and the flue vent audibly opens, but nothing ignites.

To get a flame I've been doing an off/on cycle with the Nest, the gas valve, and the boiler power. This usuals works but is getting less reliable. It helps if I poke at the wires on the hydrostat during the process.

Hopefully I just need to clean the flame sensor rod with steel wool (is that right?), otherwise this might be a ignition module issue, hydrostat-thermostat voltage issue, or even a gas valve issue. I have a pro coming next Tues but thought I would try to DIY first during cold spell.

Does anyone have insight into what might cause this, especially giver it started with the colder weather?

I don't know the boiler high-temp limit or the size of the boiler. 1200 sf house.

Comments

  • HVACNUT
    HVACNUT Member Posts: 6,300
    You'll need an electric meter to see where the circuit stops. Or if it makes it to the gas valve, then stops.
  • yellowdog
    yellowdog Member Posts: 166
    cleaning the flame sensor isnt going to help. you dont have a flame for it to prove.