atwood 8531 furnace not working

[blorb]

my atwood 8531 III furnace is having issues last year the fan would run but it would not ignite i checked voltage from sail switch and that was fine there was voltage to gas valve
took board in and it checked out good. put board back in this summer and furnace ran fine
last week furnace ran for the day and at night it would not fire.next day it ran for the day
and not later that eve. following day it would not run at all. I can here the gas valve
click the 3 times and smell gas then it will lock out. what else can i check and how do you get to ignitor as the gas valve is blocking access to it. can there be dirt or bugs inside exhaust tube. there was a lot of wasps in the furnace last fall

 

[Alfa38User]

If you hear the series of three clicks and can smell propane in the exhaust, then the only thing left is the igniter/detector. The placement of the igniter in the flame area may not be quite right or you may require a new part. (In many cases the igniter and detector are the same part and serve both purposes). You may have to loosen some stuff a bit to get to the necessary parts.