[MNFrank]

Gas (Propane) Furnace Ruud UGRA 06emaes
I've replaced the inducer blower as the squirrel cage cracked on the old one. New pressure switch.
Not enough negative pressure to close the switch.
Furnace works when I jump the switch.
Furnace has been cleaned.

I believe the problem to be lack of a baffle/restriction on the outlet on the heat exchanger. Without the baffle there isn't enough negative pressure to close the switch. What looked like scale must have been what was left of the baffle I cleaned off. What I need is a picture of the outlet on the heat exchanger to see if indeed there is a baffle and if so how much restriction.

 

[Doc Holliday]

Did you use something such as a fire rated silicone to seal the new inducer motor and did you tighten it very well? I've never had an issue with any baffle (not even certain what you mean by that) when changing inducer motors.

Are we sure that your heat exchanger is not cracked? If so that would be the foremost reasoning why there's no pressure.

 

[Doc Holliday]

Check your tubing between the inducer and the switch, if it's cracked than that's a problem. Check your exhaust vent tubing for restrictions as well.

Remove it from the furnace, bang on it a bit. Check on the roof, any bird's nest or dead squirrels in the exhaust vent? Seriously, we've seen it all and those are concerns.

 

[MNFrank]

Tubing is new.
Heat exchanger is in good shape.
Flue is clean, Horizontal run and no restriction.
New Inducer was installed with new gasket.
No as to the silicon it is not used in this application.
I appreciate the help but am looking for specific info on the
outlet on the secondary heat exchanger.

Thanks