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Induced Draft Blower tube issue

I have a Carrier crawlspace gas furnace. For some reason the tube connecting the draft blower to the vacuum sensor is heating up - it loses seal on the blower and the vacuum leak prevents the rest of the heat cycle. If I cut 1/2" off, the furnace works fine and will continue to as long as there are regular cycles. If there is a warm day, the tube fails again and must be cut.

The tube was replace about a year ago as the original was rotten. The replacement tube is for these vents. The tube is black, but changes color at the fitting on the blower and periodically on the vacuum sensor.

Any suggestions as to a cause?

Re: Induced Draft Blower tube issue

Ah yes --- the infamous tube issue.

I had an issue with the tube/ hose on my own furnace last year. In that case the hose had developed a crack right at the point where it slips onto the metal tube fitting at the blower. Unfortunately cutting the hose at that point rendered the hose to be too short ---- replacing was the only option.......... btw ..... it was the black as well. Though they may also be an orange/red color or clear.

They will eventually deteriorate or become brittle and need to be replaced but in the short time yours had been replaced doesn't sound normal.

Just a guess -------- it seems the hose is losing it's " memory " not allowing it to expand and contract properly any longer. Perhaps it may be the environment ---- the crawl space ---- may be there is a high enough humidity that's causing the hose to prematurely deteriorate.

Perhaps you can fashion a hose clamp out of some sturdy wire wrapped and tightly twisted around the hose--------- unless you can find a barrel or band clamp small enough to use --------- at the fittings and see if it helps with maintaining a tight seal .

Or ------ you might try the clear hose .
When I needed to replace mine the HVAC supply center recommended the clear hose ---- apparently is has a better silicone compound than the black and orange/red --------- though I can't confirm this. However , since replacing mine with the clear it's work fine ----- time will tell.

Too bad you weren't close by I could give you some ----- bought 3 feet of the hose.

Hopefully this helps. :)

Re: Induced Draft Blower tube issue

The hose you speak of goes to a pressure switch which should prove draft or let the furnace know that the exhaust flue is clear and the inducer motor is working properly, Usually the pressure switch itself goes but as Canuk says the hoses will fail over time, the clear hose could be your best bet though I always try to use OEM parts. Some have two pressure switches, one for Pos. pressure and one for Neg. pressure to make sure both the intake and exhaust are clear. Like Canuk said, they are a safety feature. Good Luke!!! :)

Re: Induced Draft Blower tube issue

You are right about the tiny clamp. Not sure I can find one that small, but since I've owned older vehicles, I probably have 3 leftover in the garage. :-)

I'll see what I can come up with as since the weather got warm again, it will surely fail the first day it gets cooler.

All else fails, I'll see if I can get my hands on the clear tubing.


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