Oil Furnace Repair: Troubleshooting Common Problems

man working on a furnace
  • 4 hours
  • Intermediate
  • 0-100
What You'll Need
Ladder
Old clothes
Rag
Lubricant
New filter
What You'll Need
Ladder
Old clothes
Rag
Lubricant
New filter

Some oil furnace repair projects can be done by a handy do-it-yourself homeowner. Other things should be done only by a qualified HVAC contractor or technician.

If you feel uncomfortable repairing your oil furnace, call a contractor in your area because fixing an oil heater is not only messy but requires the utmost safety and care. Below you will find several steps you can take to troubleshoot and repair your oil furnace for several common problems.

Step 1 - Check For No Firing

When the oil burner runs and you notice it just won't fire, several possible problems will have to be explored. First, the most logical reason for this problem is the oil or spark is not producing large enough to get itself over to the actual oil furnace.

Another cause could be that the safeties have become caked with soot. To fix this problem you need to check the valves on the oil furnace. Ensure they are open. Next, take a look at the oil level shown and peek inside the tank. This problem also sometimes happens when the oil has run dry. Clean the safeties of all the soot.

Step 2 - Check the Blower

Sometimes you may find the burner on the oil furnace just cycles way too much. This can happen when the blower filter is clogged or when the limit control (for heat) is not set correctly. Starting with the filter, purchase a new filter at your local home improvement center.

Replace the new filter with the old filter. Take out lubricant made especially for the blower and lubricate it. Then, make minor adjustments per the manufacturer's instructions. Last, the limit control should be checked. For this, call your local HVAC contractor and have them test and check the limit control switch.

Step 3 - Check for Smoking

A smoking flue is caused sometimes when you turn your furnace on for the first time in the winter or fall months. So, in essence it is normal. However, if the smoking persists, this means there is incomplete combustion happening and therefore your oil furnace is wasting fuel. At this point, you need to call your local HVAC contractor to adjust the burner as this adjustment can be too complicated and dangerous for the homeowner.

Step 4 - Check the Breaker and Fuse

If the fan to the oil furnace does not come on, check the circuit breaker or the fuse. Sometimes something inadvertently trips a breaker or blows a fuse. Reset the breaker or replace the fuse, if this is the issue or the cause.