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Discussion Starter · #5 ·
the problem i am having is that where the pressure switch is connected to the inducer wont close the switch. as a matter of fact air comes out of the port (which is connected to the pressure switch). when i manually activated the switch (by sucking on it), the unit runs. Does that mean that the inducer is bad?

Does this make any sense?
 

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Discussion Starter · #7 ·
i held a lighter in front of the flue and it was drafting. According to the pressure switch on the unit, it closed by a "vaccuum". However, according to the port hole on the inducer (where the pressure switch is hooked up to), the PS should be closed by pressure. It's the original pressure switch. Is there a possibility that the port hole on the inducer switched from vaccuum to pressure?
 

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Usually, only if there was a restriction.

Thats why I use a manometer. So I know what pressure the switch is sensing. And how much.

It can feel like its blowing when it is indeed drawing air in.
 

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the problem i am having is that where the pressure switch is connected to the inducer wont close the switch. as a matter of fact air comes out of the port (which is connected to the pressure switch). when i manually activated the switch (by sucking on it), the unit runs. Does that mean that the inducer is bad?

Does this make any sense?
Maybe the hose is not fitting airtight?
My unit quit working once, and I pulled the hose and cleaned the nibble that it connected to and replaced the same hose Seems I also could suck on the hose and close the switch. That was a few years ago when I had this house rented out. Not sure if I used a torch cleaner or something or just blwe through the nibble that the hose connected to. As I posed in anther thread, I just recently had to replace the hose due to something gnawing on it.

Is it possible you have a leak on the hose , and you are creating more vacuum by sucking on the hose than the unit can produce with a small vacuum leak? Or maybe the diaphram in the switch is bad? Stiff? Small tear and is still working only when suffycyent vacuum is created by sucking on the hose?
I know this out of my field, just pondering.
 

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Discussion Starter · #10 ·
I talked to somebody from Heil today and they told me that the inducer motor from that Heil model is suppose to close the pressure switch with negative pressure. For some reason, the current inducer motor is exerting positive pressure on the pressure switch. As I stated earlier, I checked the flue with a lighter and it drafted. I am replacing the flue pipe and will try to old inducer before replacing it. Hopefully that will resolve the problem. These people haven't had heat in 3 days. Thanksfully I had some extra space heaters laying around.
 

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Discussion Starter · #12 ·
No fan is running the right way. The motor is all cloaked up with residue from the chimney. That's the reason I originally thought it was bad.
 

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When someone measures it with a manometer, and says its positive. then will work on checking what is wrong.

Did you check for a blocked chimney.
 

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Did you check for a blocked chimney
.

That also crossed my mind, but he said he was or had replaced the flu. Would make sense if fan is running in proper direction and indicating positive pressure.

Hope you guys don't mind me buttin...er eaves dropping.
 

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Check for a blocked flue, check for cracks in the heat exchanger, if the blower motor is causing a positive pressure in the exchanger the rollouts should go off, so i would lean towards a blocked flue. If the header is cracked you will see water in the floor of the furnace. Also have you confirmed that the inducer is actually pushing out of the port? As mentioned above the air pulling in can feel like it is exiting. More often then not the pressure switch is just no good. You must verify a clear flue, solid heat exchanger, check co levels in flue to make sure it isnt blocked inside one of the chambers. Are the flue pipes clear. If this is a high efficiency furnace it will have pvc pipes, not galvanized. Just because the lighter shows draft doesnt mean its a clear run. More info is needed here. 80%, 90%, age.
 

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Time to check the chimney, if its an 80 then there is no secondary, look for blockage in chambers, double check for cracks, after these items are confirmed, amp the inducer, verify the wheel is true, get a pressure switch, also make sure the inducer isnt freewheeling. A pressure switch does two things, checks for inducer operation and a clear flue, thats all.
 
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