sequencer

[djustice75]

Kinda weird sequencer wouldnt open & continued to heat the appt. after no call for heat. Replaced with new 1 same thing. guess do to heat in the air handler. Any one ever experience that? Replaced with contactor fixed the problem. just kinda weird.

[dandyme]

what's weird? the contactor or what it did?
not so sure the problem isn't still there.

it's either a stuck sequencer a meter and knowing how to use it would inform you of that condition or there's something shorting across the element.

[kls-ccc]

I have had this happen before, the control compartment where the sequencer is mounted gets to hot and since teh sequencer is heat operated it won't cool down enough to shut off. The ones I found the sequencer was ok but there was an airflow issue causing the extra heat. You may have just put a bandaid on a bigger issue.

[gravity]

I have had this happen before, the control compartment where the sequencer is mounted gets to hot and since teh sequencer is heat operated it won't cool down enough to shut off. The ones I found the sequencer was ok but there was an airflow issue causing the extra heat. You may have just put a bandaid on a bigger issue.

Have seen this before ^^. Maybe some dampers got closed, or weak blower motor, etc...

Also, a lot of 1st company air handlers will do this. it's not a airflow problem but, more of a design problem.

[welling service]

I don't think the control compartment can get hot enough to cause the sequencer to remain closed without roasting the whole compartment.
Did you check for 24 volts at the sequencer?

[kls-ccc]

I don't think the control compartment can get hot enough to cause the sequencer to remain closed without roasting the whole compartment.
Did you check for 24 volts at the sequencer?

On the ones I've run into the compartment was 110 - 120 degrees with the compartment open, sequencer closed no control signal. Shut the power off for 5 minutes and re-energize, everything would be off. raise the stat, let it run for 3 minutes and it wouldn't shut down. Found where the compartment wasn't sealed from the plenum and hot air off the plenum was going into the compartment.

[54regcab]

I'm not sure why air handlers don't use contacters OEM.

[gravity]

I'm not sure why air handlers don't use contacters OEM.

The contactors cost more. Sequencers boost efficiency because they are "timed"

I will replace sequencers with a rated contactor.

[welling service]

I have never encountered this problem. I would think that a sequencer would require more than 120 degrees to make the switch but don't know for sure.

On the ones I've run into the compartment was 110 - 120 degrees with the compartment open, sequencer closed no control signal. Shut the power off for 5 minutes and re-energize, everything would be off. raise the stat, let it run for 3 minutes and it wouldn't shut down. Found where the compartment wasn't sealed from the plenum and hot air off the plenum was going into the compartment.

[welling service]

I went to Honeywell web site and their sequencers are rated to work in ambient temps ranging from -20F to 162F.

[pacnw]

The contactors cost more. Sequencers boost efficiency because they are "timed"

I will replace sequencers with a rated contactor.

do you use any in particular?

standard or quiet operation?

I have been thinking about this on a few trouble units that seem to go through them on a regular basis.

[djustice75]

I don't think the control compartment can get hot enough to cause the sequencer to remain closed without roasting the whole compartment.
Did you check for 24 volts at the sequencer?

yep when the termostat was satisfied it dropped voltage at the sequencer.

[djustice75]

lol was neither & trust me bud have meter & know how to use it. Also what the sequencer was doing. replaced with contactor. insulation looked fine but may have blown up when the blower came on concentrating heat on wall behind sequencer thought of that after the fact. So gotta go back to check. Wasnt so much stuck because when i took the door off & cool air entered the sequencer would open up!