Hi, I have a second hand Reznor model SCB125-6 that came out of an unused paint room at my buddies work.
It installed without issue and worked for about 2 weeks before it developed this problem. At first it seemed like a faulty fan switch but after replacing it the problem remains. When the unit cycles, first the exhaust fan comes on, then the burner lights, it heats up and then the blower comes on - at least that's what should happen. About 90% of the time I can hear the "click" when the blower should come on, but it doesn't. Here's where it gets slightly more odd. After the blower fails to come on, the burner will turn off, but then the blower will come on a minute or so later with no burner lit!! Then sometimes the blower will keep going and the burner will light again, and sometimes it just shuts right back off after a few seconds.
To add even more confusion, sometimes (rarely) it works normally, and sometimes the blower won't come on at all.
Any idea's? Like I said I've already replaced the fan switch and that didn't solve the problem. This unit also has a limit control, time delay relay, something called an "eco device". It's also worth noting that the fan switch is also wired to a 24v transformer which I was told probably acts as some sort of delay. As you can probably tell I'm only vaguely familiar with HVAC so any help is appreciated.
Thanks,
Mike
It installed without issue and worked for about 2 weeks before it developed this problem. At first it seemed like a faulty fan switch but after replacing it the problem remains. When the unit cycles, first the exhaust fan comes on, then the burner lights, it heats up and then the blower comes on - at least that's what should happen. About 90% of the time I can hear the "click" when the blower should come on, but it doesn't. Here's where it gets slightly more odd. After the blower fails to come on, the burner will turn off, but then the blower will come on a minute or so later with no burner lit!! Then sometimes the blower will keep going and the burner will light again, and sometimes it just shuts right back off after a few seconds.
To add even more confusion, sometimes (rarely) it works normally, and sometimes the blower won't come on at all.
Any idea's? Like I said I've already replaced the fan switch and that didn't solve the problem. This unit also has a limit control, time delay relay, something called an "eco device". It's also worth noting that the fan switch is also wired to a 24v transformer which I was told probably acts as some sort of delay. As you can probably tell I'm only vaguely familiar with HVAC so any help is appreciated.
Thanks,
Mike
