Here my problem, we get back from vacation and the wife says whats that noise....what noise....the noise from the furnace...crap, I'll go find out.
Get down to the furnace and the Inducer Blower Motor has pounded out it's bearings, at least thats what I figured as it was vibrating. Next day I replace the blower with the correct model. I tore the old one apart to see if it was repairable and see the plastic cage has broke and wore through the plastic housing...WOW!
So install the new blower and turn the furnace on, goes through the proper sequence and after flame ignition the pressure switch shuts the gas off after about 6 sec. I figure the flame sensor needs to be cleaned so I pull that out and steel wool it per the manuf. recommendations. Reinstall and same thing happens plus I look for the flashing code and see 3 flashes...pressure switch code. Again from the manual it can be the intake or exhaust air, wiring or bad switch. The furnace has been running fine before we left and as my house sitter didn't notice anything wrong with the heat so I don't think the intake and or exhaust has been clogged.
So I decide to buy a pressure switch, installed it and the furnace ran for 5 min. or so, so I figured it was fixed and went back to work. Came home to no heat. Went down recycled the furnance and watched after 10 min or so the flame goes out and I get a 3 blink error code.
Now this is where it gets goofy. I removed the flame box cover and recycle the furnace, gas goes on and furnace works fine...as long as the air tight cover isn't installed. So this leads me back to the intake/ exhaust air, as my piping goes up thru 2 stories and it's winter in Michigan and I'm no mountain goat I cut my intake pipe and use my shop vac.....no debris is sucked down the pipe and the inducer motor doesn't appear to be having any problem and I can hear the exhaust when standing outside.
I plan on putting back on the cover and leave the 3inch PVC furnace pipe unconnected to the stack. I assume if I don't have a problem then I must have a plugged intake stack, If I still have a problem...I HAVE NO IDEA WHATS WRONG (this is what I expect).
Other possibilities:
New Inducer Blower is sucking to much air for the long intake stack to supply to the furnace and having the lid off the box helps make up the missing air?
Flame roll out sensor is bad...but don't get the correct code??
Flame sensor is bad, but likes the extra air????
I just find it hard to believe the inducer motor doesn't have something to do with this as it is the only thing that has changed in the past 12 years! but it is the correct model and seems to be running correctly and all the vacuum lines are hooked up.
Any suggestions would be appreciated.
Chris
Get down to the furnace and the Inducer Blower Motor has pounded out it's bearings, at least thats what I figured as it was vibrating. Next day I replace the blower with the correct model. I tore the old one apart to see if it was repairable and see the plastic cage has broke and wore through the plastic housing...WOW!
So install the new blower and turn the furnace on, goes through the proper sequence and after flame ignition the pressure switch shuts the gas off after about 6 sec. I figure the flame sensor needs to be cleaned so I pull that out and steel wool it per the manuf. recommendations. Reinstall and same thing happens plus I look for the flashing code and see 3 flashes...pressure switch code. Again from the manual it can be the intake or exhaust air, wiring or bad switch. The furnace has been running fine before we left and as my house sitter didn't notice anything wrong with the heat so I don't think the intake and or exhaust has been clogged.
So I decide to buy a pressure switch, installed it and the furnace ran for 5 min. or so, so I figured it was fixed and went back to work. Came home to no heat. Went down recycled the furnance and watched after 10 min or so the flame goes out and I get a 3 blink error code.
Now this is where it gets goofy. I removed the flame box cover and recycle the furnace, gas goes on and furnace works fine...as long as the air tight cover isn't installed. So this leads me back to the intake/ exhaust air, as my piping goes up thru 2 stories and it's winter in Michigan and I'm no mountain goat I cut my intake pipe and use my shop vac.....no debris is sucked down the pipe and the inducer motor doesn't appear to be having any problem and I can hear the exhaust when standing outside.
I plan on putting back on the cover and leave the 3inch PVC furnace pipe unconnected to the stack. I assume if I don't have a problem then I must have a plugged intake stack, If I still have a problem...I HAVE NO IDEA WHATS WRONG (this is what I expect).
Other possibilities:
New Inducer Blower is sucking to much air for the long intake stack to supply to the furnace and having the lid off the box helps make up the missing air?
Flame roll out sensor is bad...but don't get the correct code??
Flame sensor is bad, but likes the extra air????
I just find it hard to believe the inducer motor doesn't have something to do with this as it is the only thing that has changed in the past 12 years! but it is the correct model and seems to be running correctly and all the vacuum lines are hooked up.
Any suggestions would be appreciated.
Chris
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