PA34 Janitrol Heater Trouble

[BGF_Yankee]

I seem to be able to reliably get my B3040 heater to function on the ground, but once I climb into the air, the hot air stops coming. Anyone else have an issue and give me a place I might start? I can verify power is going to the unit and that the blower works (on the ground and in the air). As I said, it's heating on the ground, so I know it's at least getting enough fuel and spark to function there. I'm tending toward the air pressure switch being the culprit, but wondering if there's an easy way to test it...

 

[JAWS]

If you aren't a certified mechanic with experience with these heaters, don't mess with it. Janitrols can be fussy when not petted and stroked nicely. They can also be deadly!

I haven't touched one in years and don't miss them at all.

 

[Banjo33]

Harold Haskins inc. is my recommendation for anything Janitrol-related.

 

[GroundPointSeven]

If you aren't a certified mechanic with experience with these heaters, don't mess with it. Janitrols can be fussy when not petted and stroked nicely. They can also be deadly!

I haven't touched one in years and don't miss them at all.

No joke, had a bad experience with one at night over mountainous terrain..never again.

 

[BGF_Yankee]

Oops...oh well. After about 2 hours with the service manual and 30 minutes on the phone with Hartzell Aircraft Tech., I determined it was the air pressure switch. Ordered a new one, replaced it (as per HET's instructions), and it works fine now. It was very obvious what was wrong when I removed the old switch. I think some threads were damaged either in the nut or connector and was not allowing a tight seal. Big props to Air Power, Inc. for having one overnighted to me for a minimal fee. Also big thank you to Allen (I think it was) at HET for taking the time to talk to an end user in the field. Otherwise, my flight to Florida the day before Thanksgiving at 17,000 feet would've been awfully cold!

And before you guys start, it was all supervised by my A&P/IA who is a MX instructor on my airfield. He tasked me to try and figure it out for myself.