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Honeywell Smart Valve Problem

Seann Member Posts: 1
As it always happens, I fired up the propane forced air furnace a few weeks ago to test everything before winter and no issues. Now that its subfreezing outside, the darn thing decides its not going to work.

I cycle the furnace on
First blower comes on
Audible "click" of the pilot valve
HSI glows
Pilot ignites
HSI goes out
No burner ignition

At this point, I originally assumed a flame sense issue. I cleaned the rod and the chassis around it. In series testing shows 1.9uA current. I tested resistance between the SmartValve body and the chassis, roughly 2ohms. So now I'm thinking the flame sense is good, especially since the HSI goes out on pilot ignition, and if I blow out the pilot the HSI comes right back on.

I never hear an audible click for the main valve opening, though I don't remember if I used to.

I'm thinking either my gas pressure is too low? OR the SmartValve is bad?

Is there any further testing I should do? Could it still be a sensor or power issue?

Thanks in advance guys, the wife is cold!!!


  • Tim McElwain
    Tim McElwain Member Posts: 4,556
    What is the model number of the Smart Valve? You stated you have 1.9 microamps how was that measured? The reason I ask is typically you need a special adapter to check microamps on Smart Valve.
  • unclejohn
    unclejohn Member Posts: 1,778
    May be the air pressure switch. Need wiring diagram too know for sure.
    JUGHNE Member Posts: 10,322
    If the air switch did not function would you get as far as pilot?
  • unclejohn
    unclejohn Member Posts: 1,778
    Maybe. Need the diagram,