Oil Furnace Issue

I have a very old oil furnace, replace the oil primary with a Honeywell R7284 and a Honeywell non programmable thermostat (two wire system is what I have). Furnace works through a few cycles, sometimes half a day or all night. Then shuts off, thermostat comes on "heat on", but furnace does not turn on. R7284 says hard lockout...........when I hit reset it states. TT closed, limit closed. I do not use jumpers. Not sure what is is messing up. As i said will run fine.

 

How long has it been since it had a good cleaning? Oil tank included.
Take a look at the history - should be able to scroll through and display errors.

 

r,
Addressing your problem with the info provided, your furnace shuts down on safety for basically 2 reasons. Oil problems or ignition problems.

Since you are saying you can reset your furnace and it will come on it is most likely not an oil problem because if you have a plugged filter or no oil or a bad pump or coupling it wouldn't work periodically. If it shut down it generally would not restart until the problem was fixed.

An ignition problem on the other hand can be a general nuisance sometimes. Working for a while then for seemingly no reason not ignite the oil creating a lockout.

It could be a weak transformer, worn or cracked electrodes or merely misaligned or dirty, whereby sometime it will fire and sometime not until the problem becomes bad enough it won't fire at all.

If it was firing and then shutting down I would look for a dirty or weak cad cell, but since yours is not lighting at all the cad cell doesn't come into play.

I would concentrate on an ignition problem unless you can catch it doing something different.

When you reset your burner and it fires, do you get an oil smell or a puff back. If so that means you had a delay when it tried to start the first time and the oil didn't ignite. That puff back you get on the restart is unburned oil and you have an ignition problem.

As was mentioned earlier servicing the unit may solve your problems if not done recently. In either case it wouldn't and should be done annually.

Hope this helps a little.

 

Thank you very much. I do get a very slight oil smell and the puff. I will have the burner unit cleaned. All the filters have been replaced.

 

That would be a good start. It might be something as simple as dirty or worn electrodes.

If they're just dirty that would be corrected as part of the service. If they're worn they can be replaced at that time saving you a separate service call.