HVAC Questions? Ask an HVAC Expert for Answers ASAP
Hello, I see the photos and the melting/burning.What would you like to know or do? Are you planning replace the programmer?
I'm an independent heating engineer. This site is an independent site where technicians and experts provide advice and online assistance.Regarding your programmer, the warranty expired a long time ago, but even if it hadn't it would be invalidated by the use of a 5 Amp fuse. Honeywell stipulates a 3 Amp fuse to protect the circuit. Burning a printed circuit board track is a commonplace results of using a fuse of too high a rating.Regarding replacement, you can still buy the ST799. Clearly you need to replace the backplate, but it comes with a new one so that's not an issue. I can guide you in the method of installing it safely.However, the ST799 isn't good value for money. For the same money, and less, you can get a more sophisticated programmer. You could even get one that comes with a wireless thermostat. I would need to check the price of that if you're interested.
OK I can see you have things in place. That's good :-)Thank you in anticipation of your rating; it's thoughtful of you to be so proactive with it.This post can stay open as long as you need it, even after your rating. So if you have any further questions during or after tomorrow then feel free to ask.