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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8702
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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The air flow light is blinking on my water furnace premier

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The air flow light is blinking on my water furnace premier . I tried resetting but it still comes on
Welcome to Just Answer!

If the system is working properly except for the air flow light, the problem could be a clogged up air flow sensor. some use what we call 'pitot tubes' that poke into the air stream and sense the velocity of the air flow....others are 'sail switches'

You can find the 'air velocity or air pressure switch' on the wiring diagram glued to the inside of the water furnace service panel, then follow the wires to the actual switch and look it over, tell me what you find.

I am up for another hour tonight, then i will be back in the morning if i miss you tonight... there are no time limits here... take your time looking it over.

If the water furnace will not run with the air flow switch tripped, you can fit a jumper wire between the two terminals on the switch... tell me if that allows the water furnace to run or not. It is generally safe enough to leave that jumper in place if the air flow seems to be about the same as before...but I cannot guarantee it will be best to remove the jumper after that test.

We can go from there.


Customer: replied 4 years ago.

Thank you I managed to get it started . My system has a few issues

I'm going to have a professional look at it .

I appreciate your help .



Hello again, I am glad you at least got it working. Good work!

I will put the ratings box up now so that you can hopefully rate my assistance positively.


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