Replacing an old relay from a natural gas fireplace

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New Member
Jan 2, 2021
I work in a hotel which has a natural gas fireplace in the lobby. This hotel is about 25 years old. I'm currently having an issue with the furnace coming on. It was just fine the other day and now nothing.

I noticed a relay near the vent adjustment lever. I also notice that when the lever is pulled all the way back it comes extremely close to the relay. When I looked closer I could see a broken piece from the relay (possibly the core - I'm no expert). See the picture of the relay.

I haven't been able to determine whether the vent lever or flue lever is supposed to make contact with this relay but my hunch is yes.

The shots below from left to right (after the relay itself) show:

* The vent lever which pulls back into the relay
* The relay leads. The one on the left appears to go to the thermostat. The one on the right appears to go to the thermopile
* Wiring diagram for the leads and other wires

Question: How can I replace this relay with the correct part? The name on the relay is McGill for whatever it's worth.

Thank you in advance!

Link to the gas valve unit:

relay.jpg lever and relay.jpg relay connections.jpg wiring diagram for relay.jpg