There is a small red button that sits on the top of your oil burner. It is known as the “reset button.” This is the first place you should look if you notice that your heating system is not working.
Press it. If the burner fires rights up then you know that the reset button was tripped for some reason (many times it is an accident and no big deal). If you notice that this is an ongoing problem and you continually have to press the reset button for your oil burner to come back on then it’s time to call a heating professional to come out and run diagnostics.

It is not normal to have to keep resetting the red button continually and this is usually an indication that there is a problem that needs to be addressed. Ignoring the problem could cause long-lasting harm and in some cases pose a safety risk.
What is the reset button and why would it trip the system?
The small red button is a safety mechanism that is attached to the oil burner. Its main function is to turn the burner off when it detects a problem. The reset button is part of the primary control system and is connected to the cad cell relay (a sensor that monitors light).
When oil burners are turned on and running the cad cell’s main job is to sense the light of the flame that is being produced. There is should always be some sort of light when the whole system is on and working as it should.
If it does not sense any light, which is always a product of the flame being produced, it will cause the reset button to trip. This shuts down the oil burner before anything bad starts to happen. The last thing you want is for gallons of heating oil to be pumped through your oil burner without it being ignited!
Second question. I can tell that the oil burner is on. Why is the sensor not seeing any light?
There are actually several reasons this can happen. Some of them are simple fixes and some of them are not.
The following is a list of possible problems that might be causing things to malfunction. The first rounds of things are issues that will require a professional service call. The second rounds of things are ones, which you as the homeowner might be able to address and fix yourself.
- Excessive condensation in your oil tank
- Electrical connections and wiring are loose
- Flexible couplings are damaged
- Too much soot in your oil burner
- Excessive smoke
- Too much air in the fuel line
- Electrodes are either wrongly set or cracked
- Oil valve does not open like it should
- The oil nozzle is clogged
- The strainer is clogged
- Fuel pump on the burner is down
- Motor is not working properly or completely broken
- Ignition Transformer is either not strong enough or not working at all
- Primary control is defective
- Cad cell is defective or dirty
Here are issues that you might be able to solve yourself without calling a heating technician.
- Your holding tank is completely out of oil or very low (have it filled by a heating oil supplier)
- You have a blocked chimney (get your chimney cleaned)
- The oil valve is in the “closed” position (put it in the “open position)
- The oil pump is not primed (prime the oil pump a couple times)
- The oil filter is clogged (change it with a new one)

