Even though this is the OEM replacement for the original on a Sterling GG the mounting plate at the burner box has to be removed and new holes drilled to mount it. The sensor access hole needs to be enlarged slightly. It was not fun.

ACF Greenhouses: We checked with Sterling regarding your issue. They switched to the new part about 13 years ago, so very few units should be affected. They also said the only modification needed was to drill a new top mounting hole which can be done without removing any of the parts from the heater. No mod to the sensor access hole is needed.

I decided to try and tackle the part swap myself since it looked straight forward. Glad I did. The swap took me about 15 minutes and saved me a $200 service charge to have the local gas company do it!

Both a rollout switch and controller board were purchased.

The technical customer service support was EXCELLENT.

Troubleshooting help from someone with knowledge and experience provided confidence in ordering the correct part.