I have a HEIL gas furnace located outside my house,I found that with the front panel removed it operates perfectly,however with the panel in place as normal the burner will light but will go out. Once I remove the panel I hear the gas valve click and its running perfect. I replaced the pressure switch but nothing changed. The draft inducer fan is running

Model number ?
If filter clean?
Is indoor returns clear and open?

Model PGAA47F1K4
Filters are new
Returns are clear

If the unit has a flame sensor clean it carefully. Very fine sand paper OR steel wool will work. Check for loose wiring especially at the Honeywell smart valve if so equipped. Be especially careful of cleaning the flame sensor since the igniter hangs over the sensor and is delicate.


Usually something like this has to do with airflow into the unit for combustion or loose wiring. Also check the safety switch on the blower access door since it can be moved around a bit when replacing the front door of the unit.

Post back with results

I cleaned the flame sensor as best as I could and I don't see any loose wires
What could be causing a lack of air for combustion?

You said the furnace is located outside your house.

Is it in a room built for it?
Does this room have combustion are provisions?
Why is the furnace outside your home? Is it a trailer/mobile home?

HOW long has this unit been installed in this room?

Uhh, I was assuming it was a package unit, my bad!

The entire a/c furnace is one unit located next to the house with the ductwork going into the crawlspace and up into each room. The unit is not covered in any way and this is how all the units are setup in my subdivision I believe that this unit is called a packaged unit thanks

Here is your technical support doc.

http://icpindexing.mqgroup.com/documents/086477/46204100400.pdf

Install doc.

http://icpindexing.mqgroup.com/documents/086477/46201100101.pdf

Service manual and a nice one at that.

http://icpindexing.mqgroup.com/documents/086477/46208100100.pdf

Something has to be related between the door that you remove and that the unit will not work when the door is back on. Which panel are you talking about exactly? Is it the one that the burners are behind?

Yes it is the front panel which covers the entire half of the packaged unit which is the furnace side it gives access to the burners,gas valve,circuit board, pressure switch and draft inducer fan

After looking at all the service literature that I posted I can see nothing that could cause your problem. I am not saying the unit does not have a problem it is just a simple unit and this is a very strange situation with it turning off just because the door is put on the front of the unit unless somehow by attaching the front door it is causing the flames to come out of the burner area and tripping the flame roll out disc( NOTE: I believe your rollout switch has a manual reset so unless you are reseting the roll out switch on every shut down event disregard the roll out switch mention in this post). It is also a possibility the exhaust blower or other wiring is intermittent or loose causing the furnace to shut down. The exhaust blower has to be tested with a manometer as per the service manual.

You might try and have the unit running when you put the panel back on and see if you can look through the slats in the panel to see if anything unusual happens that might point to the problem. Sorry but from long distance I cannot see or test anything.

If I have not mentioned this before keep a copy of a 3 documents I posted on your computer since they will come in handy some day.