Dear Inspector,

This month I would like to discuss a system that is timely for the season; heating. I'm sure most of us are rather familiar with the basics of heating systems so I will attempt to provide some of my practices for increased inspection accuracy without spending much extra time for investigation. Some of these practices may exceed published inspection standards of practice.

1) Oil boilers and furnaces: with the flame off I open the inspection door to observe the refractory (combustion) chamber for deterioration or cracks. Once I have completed a visual I like to activate the furnace and look at this chamber once again and check that the oil burner flame is not directly striking the back wall. A properly adjusted burner flame will turn upwards and just barely lick the back wall of the refractory chamber. With the appliance running and the flue hot (this can take up to 10-minutes) I hold a mirror at the barometric damper. If the mirror fogs then the products of combustion are spilling and the unit requires immediate attention by a heating technician. I also advise my clients that any oil-burning appliance absolutely requires annual tune-up by a qualified technician. If not maintained oil appliances can malfunction and be dangerous, or at minimum, blow back real smelly fumes into the house.

2) Gas furnaces and boilers: For gas furnaces I like to try to see as much of the heat exchanger as possible. Many older natural draft furnaces have a flame shield that blocks much of the view inside the exchanger. When the screws will move easily, I remove the flame shield to better inspect the furnace. With the furnace or boiler operating and the flue hot (remember, this can take up to 10-minutes depending upon flue length, temperature, etc.) I hold a mirror at the draft diverter. If the mirror fogs the products of combustion are spilling and the unit requires immediate attention by a qualified heating technician. Fan assisted (induced draft) furnaces have no draft diverter. All combustion and dilution air enters through the front of the combustion chamber. On these furnaces I hold the mirror at the front of the combustion chamber, if it fogs the products of combustion are not properly exiting up the flue pipe. Also be on the alert for cracked fan housings on these induced draft furnaces.

The above are just a few tips to help you with your inspections. One more item: I always recommend to my clients that they purchase and install per the manufacturer instructions a carbon monoxide detector for increased safety. I recommend these even in all electric houses. If there is an attached garage or fireplace, potential sources of carbon monoxide may exist.

Mike Casey
Kaplan Professional Schools
Now You're Ready For Business!™