I am trying to troubleshoot problem with CD-45K heating unit which was installed in our PA-31 350 Chieftain in 2002 (s/n 31-8152010). Previously we had original Janitrol unit (s/n 65D79-2).
Signs: The heater disconnects in the air or on the ground without a clear reason. We cannot restart it after that.
We replaced fuel shut-off valve, clean all ducts and had
whole unit inspected for possible failure without success unfortunately. Heater still doesnt work as it should.
We have noticed that each time we clean or replace spark plug heater works for a while and then it disconnects again till next cleaning. we suspect somekind of ignition problem however its hard to tell what should we do to make it work all the time.
Anyone had the same problem?? Any ideas what are we doing wrong or where the problem can possibly exist?
We had a similar problem with our Aztec. First low heat output, then cutting out until we'd clean the ignitor.
Go to www.aircraftheater.com, C&D's site. Go through all the troubleshooting info. Call them, it's their heater and they have great support. I'd start with a new fuel nozzle. It sounds to me that your fuel isn't atomizing properly and it's fouling the ignitor. Don't try to clean the old nozzle. Check the color of your exhaust "stain", it should be light to medium grey,not black.
