Routine Furnace Cleaning
All winter long, a furnace heats and circulates air. A properly maintained filter will prevent most particulate matter from getting inside the machine. However, some very micro-sized stuff and fumes can get in. My home has a cigarette smoker and a cigar smoker. Twice a year (fall and spring), I open up the furnace and tidy up.
Safety is very important. The control module and blower motor are electric. There is a control module and a transformer where voltage and current are normally present. Care must be taken to avoid bumping any adjustments for gas metering and over-temperature cutout. The edges of sheet metal are sharp. Hand protection is highly recommended.
If you feel you are not capable of cleaning your own, spend for a technician to make a house call. Better safe than sorry.
For this, you will want:
a. a vacuum
b. an extension hose
c. a crevice tool
d. a dusting poof
e. work gloves (cotton is fine, leather is acceptable)
Step 1: Before you begin
Turn the power off to the furnace. There should be a switch next to the furnace. if there is not one, turn the power off at the circuit or fuse panel.
Step 2: Start with the exterior
The outputs of the furnace can get quite hot. Removing cobwebs, dust, and residues will alleviate the odor of a furnace firing up after having been dormant for a while. Clean the ductwork at the furnace so when the cold weather returns and the furnace activates, you won't 'smell something burning'.
Step 3: Open up
The inside is where all the business gets done. Air comes in, gets heated, and goes back out. Removing the accumulated debris internally, the risk of fire is reduced and sensors may read with more accuracy. Moving parts will experience less friction, slightly increasing efficiency.
Step 4: The lower portion
This is a sensor which detects when the lower cover has been removed.
Notice that I have maintained a distance of 2cm between the tip of the crevice tool and the surface of the control module. The longer you keep the tip still, the more crud will come loose and get sucked up. No need to hurry here.
Vacuum the sides of the furnace housing.
The main blower, air filters, and system control module are almost always located in the lower portion.
The blower is a squirrel cage design. Air comes in the sides near the shaft and exits radially, funneled upward by the blower cover design. Debris in the lower area can work its way into and around the shaft and bearings. Chunks of dust bunny may get sucked in then pass through the airway system and get blown out into another room.
The module has electronic components such as relays, transistors, resistors, diodes, and so forth. When vacuuming the module, be careful not to bump any of the components with the tip of the crevice tool. If any of the electronic components get bent and make contact with other components, a short circuit condition could render the module non-functional.
Step 5: The filters
Filters are made from a cardboard frame which supports a mesh of woven fibers or porous paper. The denser the weave and smaller the pores, the finer the particles which are blocked but this also reduces the time that the filter is useful. The more particles trapped in the filter, the less air that will flow through the rest of the system.
Gently vacuum your filter or replace it.
A clean furnace is a happy furnace!