[giantsfan]

My Lennox heater starts up fine runs for about 4 to 5 mins. then the burners shut off.Everything else stays running except the burners.The front panel lights up a open rollout switch which I replaced hoping that was the problem.But that did not fix it.HELP PLEASE

[giantsfan]

keeps blowing air

[SteveKJR]

It could be that the sensor in the heat exchanger is the problem. Some units have several heat sensors with or without a reset.

When the unit shuts down, disconnect each sensor and ohm them out before they cool down - if you get a reading across all the ones you checked then the problem is elswhere - could be in the board.

SteveKJR

Originally Posted by giantsfan

My Lennox heater starts up fine runs for about 4 to 5 mins. then the burners shut off.Everything else stays running except the burners.The front panel lights up a open rollout switch which I replaced hoping that was the problem.But that did not fix it.HELP PLEASE

[giantsfan]

Well come to find out what was wrong with my unit was that the installer built a box in my attic for a filter for my unit.Why they would do something so stupid is beyond me.I had to air draw to my unit come to find out so I started checking my ducts to see if the came loose or became torn by something.Come to find out when I started looking around I found the box with the filter and took it out and relocated it to a more convient place to get to change.

[SteveKJR]

So, it sounds like the high limit was doing the job - the filter caused an air flow problem by reducing airflow across the heat excahnger (that is if the filter you found was completely clogged up). As a result, the temperature in the heat exchanger exceeded the temp on the sensor and the unit shut down.

Good find. Keep an eye on those filters - they can cause problems.

SteveKJR

Originally Posted by giantsfan

Well come to find out what was wrong with my unit was that the installer built a box in my attic for a filter for my unit.Why they would do something so stupid is beyond me.I had to air draw to my unit come to find out so I started checking my ducts to see if the came loose or became torn by something.Come to find out when I started looking around I found the box with the filter and took it out and relocated it to a more convient place to get to change.