Changing the sludge filter on your heating oil tank should be part of your home maintenance routine. You can do it anytime of year, but an ideal time is before the cold weather sets in as part of your furnace maintenance plan. The filter, which is located on the oil tank in the fuel line, can be changed with a few tools in only about a half-hour. Replacement filters can be purchased from heating supply stores, home centres and building supply centres.
Find the oil filter on the outside of your heating oil tank. It is mounted near the bottom of one end on most tanks. It looks a little bit like a water filter or similar encased filter.
Turn off the valve between the tank and the filter to shut down the fuel flow from the tank. Do not remove the filter until this has been done, or you will have a major oil spill to deal with.
Position a drain pan of some sort under the filter housing to catch any oil dripping when you remove the filter housing. An old pie pan works great for this. Spread a little sand or cat litter in the bottom of the pan to absorb any oil drips.
Locate the bolt on the top of the filter housing. Turn the bolt counterclockwise with a wrench and remove the lower housing and filter. Separate the filter from the housing by pulling it up and out of the housing. Set it in the dripping pan for now.
Insert a new housing gasket on the housing and rub a small amount of heating oil on it to help it seal. Drop the filter into the filter housing and position the lower housing back on the filter housing at the tank. Install the mounting bolt and tighten it with a wrench.
Open the valve on the fuel tank. Locate the small bolt on the top of the filter housing, this is the bleeder for the filter. Open it with a wrench to remove the air from the filter. Bleed the furnace at the pump inside the house.
Wipe down the filter housing with a clean rag to remove any fuel oil that may have spilt on the outside. You can use a degreasing detergent if you have a lot of material on the housing.
Dispose of the old filter, dripping pan and any contaminated rags or cat litter properly. Check your local government or refuse company to find out how to best dispose of the materials.