Nordyne E2EB 015 Sequencer not sequencing
Posted: Tue Nov 16, 2010 12:48 am
Hi! Our troubles began when the heat wasn't coming, fan worked fine when turned to on and with the a/c - nothing with heat setting. So after some diagnosis and searching on here I narrowed it down to the sequencer (or so I thought)
Ordered a new sequencer, while waiting for it, took the whole blower out and cleaned it per instructions found on this site. My only issue there is that I'm not 100% sure if I hooked the capacitor leads back to the correct places on the cap itself although it does not appear to be a polarized cap.
Got the new sequencer in, d/l'ed the schematic and manual for my model from Nordyne and followed it to the T. Installed new sequencer and the fan and heat were coming on as soon as power was applied from the breakers - would stay on until power was shut off. With power at the breaker off (leads still conected on sequencer) I checked for continuity across M1 and M2, M3 and M4 and was showing continuity across both but not across M5 and M6. So I thought I got a bad sequencer out of the box, called and got a new one sent right out. Meanwhile was controlling heat with breakers to stay warm and it was working fine, all coils getting hot.
Also replaced the t-stat with a digital model and replaced the fan relay (wanted a new t-stat anyway).
Got the replacement sequencer and went to put it in. Made sure power was off and pulled the leads off the sequencer that was currently installed, checked it with my meter and it checked ok - very odd I thought. So... I hooked it back up and turned the power back on - fan and heat coils did not come on right away as they had been, thought that was a good sign and sent a call for heat from the t-stat. Fan came on but only the third coil came on, checked for power off M1 and M3 while it was on, no voltage out of sequencer on those terminals. Thought, ok maybe it is a bad sequencer after all. Swapped it out with the 2nd new one and it is doing the exact same thing.
I have checked the coils, good contintuity (very low resistance), none of them are grounded. I've rechecked the wiring about 50 times to the schematic, all is as it should be.
Also checked the control from the t-stat, turns on and off by temperature control as it should, stays off when switched to off, a/c works normal.
Checked for 24volts across the sequencer - good.
What am I missing here? Surely I can't have two new sequencers be bad...
How do I check the limit switches? They are the self-resetting type.
Any guidance will be very appreciated, the wall is starting to look tempting to the noggin'....
Thanks! - Jeff
Ordered a new sequencer, while waiting for it, took the whole blower out and cleaned it per instructions found on this site. My only issue there is that I'm not 100% sure if I hooked the capacitor leads back to the correct places on the cap itself although it does not appear to be a polarized cap.
Got the new sequencer in, d/l'ed the schematic and manual for my model from Nordyne and followed it to the T. Installed new sequencer and the fan and heat were coming on as soon as power was applied from the breakers - would stay on until power was shut off. With power at the breaker off (leads still conected on sequencer) I checked for continuity across M1 and M2, M3 and M4 and was showing continuity across both but not across M5 and M6. So I thought I got a bad sequencer out of the box, called and got a new one sent right out. Meanwhile was controlling heat with breakers to stay warm and it was working fine, all coils getting hot.
Also replaced the t-stat with a digital model and replaced the fan relay (wanted a new t-stat anyway).
Got the replacement sequencer and went to put it in. Made sure power was off and pulled the leads off the sequencer that was currently installed, checked it with my meter and it checked ok - very odd I thought. So... I hooked it back up and turned the power back on - fan and heat coils did not come on right away as they had been, thought that was a good sign and sent a call for heat from the t-stat. Fan came on but only the third coil came on, checked for power off M1 and M3 while it was on, no voltage out of sequencer on those terminals. Thought, ok maybe it is a bad sequencer after all. Swapped it out with the 2nd new one and it is doing the exact same thing.
I have checked the coils, good contintuity (very low resistance), none of them are grounded. I've rechecked the wiring about 50 times to the schematic, all is as it should be.
Also checked the control from the t-stat, turns on and off by temperature control as it should, stays off when switched to off, a/c works normal.
Checked for 24volts across the sequencer - good.
What am I missing here? Surely I can't have two new sequencers be bad...
How do I check the limit switches? They are the self-resetting type.
Any guidance will be very appreciated, the wall is starting to look tempting to the noggin'....
Thanks! - Jeff