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Lochinvar KBN 080 Swirl tube question

JUGHNE Member Posts: 11,074
Had to change the fan on the KBN, noticed the small 8 ports around the swirl tube/venturi tube seemed plugged.
Are those the actual gas passages into the blower......around the tube?
There is no other way the gas gets into the tube/fan inlet that I can see.
Last valve I looked at when changing fan those 8 ports were open.

I know the fan died (low fan lock out), there is 120 v to the power plug on the motor and when the other plug is removed the fan does not run as it did previously with that test.


    JUGHNE Member Posts: 11,074
    Must not be any ModCon people on today.
    My real question was how does the gas get into the air stream of the venturi tube. It seems it flows thru the 8 small 1/8" "mouse hole" shaped openings on the circumference of the outside of the black plastic tube?
    I was concerned they were partially plugged.
    A call to tech support was returned in about 45 minutes.
    The tech guy could not explain how the gas got into the air stream, he went off to ask someone and returned saying the 8 openings were the gas inlet.....maybe figured that was what I wanted to hear.
    He also said these "older units" can be an issue. This ModCon was built in 2009, installed in 2012. So the perception of these things aging quickly is even pervasive within the company.

    Anyway, cleaned the opening best as possible, back together with the new fan and all is well.