Diplomat Furnace by Lennox (natural gas) not able to initialize

[lbrowne]

Hello, I have a furance that is acting up. when the thermostat reaches belwo the set temp the furnace tries to start. It has 5 burners/jets or whatever you call them. It tries to light a set amount of times, I think 4 times, and then gives up.

The flames start on the jets, they run for approx 10-30 seconds, then shut off. The furnace tries this sequence about 3-4 time and then shuts down and won't try again unless I jostle with the thermostat. Not good when you wake up cold and theres 2 young kids in the house.

When it does catch it promptly heats the house to the desired temp and shuts down again like it should.... what can i check?

[lbrowne]

I can't find a model number anywhere on the outside - I believe its called a forced air unit? Maybe I have to take off a panel to get the model number.

[applianceman18007260692]

next to the ignitor is a sensing element you may want to try and shine that up with some emory cloth

[lbrowne]

any idea on what this looks like? Should I take a pic and post it?

[applianceman18007260692]

take some pictures of the burner pilot assy and post

[lbrowne]

here she is in all her glory...

 

[lbrowne]

and here

[kdog]

if you look into the ends of the burners,you will see the pilot/orifice ass'y attached near the other end of one of the burners, when the unit fires up,a spark ignitor will energize and light a pilot light(turn your t'stat up and watch this) once the pilot flame has been established- the burners will ignite,when that happens,the pilot flame is sucked up into the burner flame,and if there is a carbon buildup on the pilot sensing bulb,or a poor ground,the valve will be fooled into thinking the pilot has gone out and thus shut down the burner- to cure this,it will be necessary to remove the pilot ass'y,and clean it up,or replace it,and at the same time,ensure that all the ground wires etc. are attached to good clean,corrosion free parts of the metal chasis.

[lbrowne]

Ok, so is this something for a do-it-yourselfer?

Hate to sound dumb, but could edit a pic circling what i have to let or what has to come out first etc?

thanks for your help so far!

[kdog]

the picture that you posted of your unit are from the outside of the unit and the ignitor/pilot ass'y is not evident- it is located inside the burners- since this is a fairly sophisticated device,you may not want to chance servicing it yourself as it does require a bit of mechanical/eletrical aptitude and understanding. if you feel uncomfortable with it- call in a gun as you don't want to mess with gas/heatsource and endanger yourself or your family.