My unit will run one heating cycle, achieve the desired temp and kick off. When the thermostat calls for the next cycle it will fire up and blow heat for maybe one minute or not at all! I will then have to turn off the thermostat several times and back to heat to make it come on. I replaced the thermostat and no change, Please help.

Provide the unit model #. XL-1100 is just a model name.

Maybe a mod can link these up?

I had a tech. come out and look at my unit siad it would not fire so I bought a new ign. And it is doing the samething it will fire sometimes and light and then others it just breaks down and just hit and miss sparks the board throws no codes the tech. says he has no idea and has been a tech. for 20 plus years never seen this it has 24 volts at the ign. And still won't work he checked ign. And said it was good someone please help we have no heat with kids!!