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BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22514
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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Can't get a 175 prestige to initially fire---Gas pressure at

Customer Question

Can't get a 175 prestige to initially fire---Gas pressure at the inlet port is 7.7, no drop when the ignitor sparks, also no voltage at the control module.The install is at 10,500'. Backed the throttle all the way in and out, no joy. Can't do a combustion analysis since it won't fire. First fixture off the main gas trunk line,even have a one inch run to the dirt leg,then a flex connector(properly sized) to the inlet.
Submitted: 2 years ago.
Category: HVAC
Expert:  BillyHvac replied 2 years ago.
are you getting gas through burner but it wont fire or you are NOT getting gas at burner?
Use reply please
Customer: replied 2 years ago.
No voltage from module to the negative pressure gas valve
Expert:  BillyHvac replied 2 years ago.
the spark and th valve receive power at the same time...if you have spark (voltage) yet no signal to valve then you have a wiring/harness issue or control module.
However I will open this for another opinion.
Customer: replied 2 years ago.
I replaced the module thought it was damaged in shipment still does not fire. It gets voltage for the ignitor but does not send any votage to the Valve. Have good pressur and gas at the inlet side of the valve