Model# DGAA070BDTB It will ignite then shut off almost instantly then try to ignite again until blower motor comes on it then tries to ignite a few more times till it shuts off and shows a steady red blink. I have replaced flame rod sensor and checked limit switches for 24v all are OK. I replaced T-Stat and checked induction switch. It still does same thing I am trying to help a low income family with four children and I have already put too much time into this job any advice would be very helpful. Thank you

Pressure switch maybe or clogged/or bad tubing going to it

The hose to the exaust vent take it off and with a hard wire stick it in and push it through its probably cloged up and won't close the pressure switch, see when the unit starts up in heat mode the exaust vent comes on and pulls a vacume another way to see if it is pulling vacume take the hose off the pressure switch while its running and put your finger on the hose to see if its pulling vacume that shoul do it. Oh the pressure switch is either chrome or black plastic with a hose rubber hose to it make shure there is no holes on hose some times rats/mice chew on them...

If all else fails post to the address below under Coleman. These guys are mobile home/Coleman furnace experts and will be glad to help.

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