Draft Inducer: Thank you for the helpful info.

[plumb krazy]

Thank you for the helpful info.

 

[Fitter30]

RH shouldn't have anything to do with your problem. Inducers that have failed was it bearing dragging fan wheel down or motor failure? Ever check voltage and amperage at motor? Did any motors have any discoloration from getting hot? Inducers usually last years most life of the furnace. Take a couple pics of furnace. This might be the service manual since you didn't supply the compleate model. In manual they show some parts get hi heat chalking.
https://www.google.com/url?q=https:...wQFnoECAsQAg&usg=AOvVaw2pmJ49tGsp5uGBoTL_TjcX

 

[Sponsor]

 

[plumb krazy]

Thank you.

 

[Fitter30]

Burner control board failure light does the same number of flashes everytime and how many

 

[plumb krazy]

Thank you.

 

[Fitter30]

Fan is running pressure switch not made. Take a pic of the flue sticking out of the roof and guess how much it sticks over the peak.

 

[plumb krazy]

Thank you.

 

[plumb krazy]

Thank you.

 

[Fitter30]

Usually a flue within 10' of the peak needs to be 2' above. Need to do some more checking. Looked at that venter fan never seen one round with a propeller and not a fan wheel. When the inducers were changed were the motors open to the windings and dirty ?

 

[plumb krazy]

Thank you.

 

[Reach4]

That sure is a popular part. Even Walmart offers a replacement. https://www.walmart.com/ip/Packard-...ordyne-903404-Combustion-Air-Blower/114949498

Is that device before or after the flame?

 

[Fitter30]

That sure is a popular part. Even Walmart offers a replacement. https://www.walmart.com/ip/Packard-...ordyne-903404-Combustion-Air-Blower/114949498

Is that device before or after the flame?

Before

 

[plumb krazy]

Thank you.

 

[Fitter30]

I went and read about flue placement/height codes and saw the requirements based on safety but could not find any info about the practicality regarding air flow with regards to the inducer motor facing to much back pressure.

I think I may have gained some insight about the "morning" phenomenon, by finally correlating the fact that we have a thermostat with day/night temp control and it is in the morning when the system attempts to raise the temperature abruptly, so the system gets a bit hotter than when it is simply maintaining the temperature and it starts to run in short cycles. I am guessing that the extra work concentrated in a short span of time causes the inducer fan motor to strain and then the fault occurs.

It's been a year since I last I had removed and replaced one of the fans, but as I recall there was a moderate amount of dust. Nothing that seemed out of the ordinary. I do recall that on one occasion I cleaned one up and re-installed it while waiting on a replacement to arrive, and it remained intermittently problematic until it was retired a few days later. In other words, the dust may have harmed it, but cleaning it did not seem to help it.

Thank you for helping me bounce some ideas around.

I will appreciate any further info anyone can share.

Thank you.

When unit comes out of night set back there is no short cycling thermostat should be calling for heat till it meets temperature. A furnace shouldn't have any strain they should be able to run without any problems for years. Next time unit short cycles raise thermostat setting to 85* that should take the thermostat out of the picture. What brand and model of stat?

 

[plumb krazy]

Thank you.

 

[Fitter30]

LUX TX500E

I was not saying that the thermostat was calling for the short cycle, I was explaining that the system seems to do a series of frequent short cycles in the morning, and I am correlating that to the effort to raise the house temp 4 degrees to the day temp.

The short cycles may be unrelated to the draft inducer issue, but the pattern ultimately reveals a weakness of the draft inducer motor.

The short cycling may be due to the heat limit switches activating.

The hi limlt, aux limit and pressure switch are all in series with the thermostat. If any one of these opens up burner drops out. Limit switch trips 1 flash on igniter board. Need to start somewhere guessing usually doesn't work very well. Thermostat should be program with a 5 minute time delay between cycles.

 

[plumb krazy]

Thank you.

 

[Reach4]

Yes. What would you suggest?

I saw a suggestion in #14. I saw info in #16 that I could turn into an action item if I could probe voltages during the drop-out. Can you locate any of the cut-out switches listed in #16? Can you get meter probes on the connections? Do you have a meter?

You seem defensive.

 

[plumb krazy]

Thank you.

 

[Fitter30]

When power is cycled control resets and clears memory. Take pic of the wiring diagram that i know were looking at the same one. Inside blower door.