by bgsengine » Sat Feb 15, 2014 4:15 pm
You need to check the system air pressure.
On the side of the heater on the label- one of them, you should find an Operating Pressure specification (or will need the heater brand and *exact* model number) - Usually between 3 - 6 PSI - To get an accurate reading requires a low pressure gauge (# HA1180) There's an adjustment screw in the end cap next to a plugged port (or the port will have a gauge in it) - Behind that screw is a spring and check ball - the adjustment screw applies pressure to the ball to control system air pressure (Part number PP217 for the kit, assuming it is a Desa variant) - If you plug that off (which you might be doing with the rag) it increases system pressure because the air bypasses that check ball as system pressure builds past the spring weight. (You'll feel air sputtering or blowing out that relief hole in that adjustment screw)
a "seat of the pants" adjustment would be to turn the screw in/out to adjust pressure until flame starts to shoot past the end cone of the barrel , and then back off just a bit until you have an orange hot glow of the cone, but no flame blowing past.
9 times out of 10, when it is a pressure problem, we find a cracked end cap, or someone's been messing with the adjustments to try and "fix" it
Have also found heaters with rotted hoses coming off the air pressure outlet of the air pump.
First thing we do with *every* one of those that comes in the shop is to check and verify the air pressure.
If you got your brand and exact model handy, I can tell you part numbers you'll need for whatever is found wrong.
They are technically very simple machines - very little to go wrong with them most times, and 95% of the problems are either a nozzle, or an air pressure problem.
Photocell would be a problem only IF the heater otherwise burns correctly and shuts down.
We did have a Dura-Heat that was shutting down like that as it got warmer , which was a bad circuit board assembly.
So, it would help a lot to review the posting rules and include your make and model numbers of the equipment. (and serial if you have it, though that's rarely needed.)
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)