During normal furnace maintenance or a utility company inspection, a technician may discover a problem with your furnace serious enough to require disconnecting it. In legal terms, it means the furnace is not in compliance with the Ontario B149 Gas Code. The technician may “red tag” the furnace, turn it off and notify the gas company of the situation.
In the best red tag scenario, you receive a ‘B’ red tag, which means the furnace can be safely used for 30 to 45 days, during which time the problem must be remedied. An ‘A’ red tag signifies that the furnace must remain off and disconnected until repairs are made and the furnace is re-inspected.
Red tag issues are furnace deficiencies that create a potential fire hazard, health hazard or a threat to human life. The number one red tag problem is a cracked or otherwise defective heat exchanger, but a defective flue or failing ductwork, among other things, may trigger a red tag also.
A cracked heat exchanger is dangerous because it may cause incomplete fuel combustion that produces dangerous carbon monoxide emissions. Carbon monoxide is a “silent killer” because humans cannot detect it until it is too late. Sickness, convulsions and even death may result from breathing carbon monoxide.
If your furnace is shut off during cold weather, you are faced with quickly deciding between possibly expensive repairs or replacement. Try not to panic, however, so that you can make a reasoned decision that you will not regret later.
If a new heat exchanger is needed, first consider the age of the furnace. Most furnaces have a life span between 15 and 20 years. If yours is over 10 years old, the best decision is probably to replace it with a modern, high-efficiency unit. This makes sense if the cost of replacing the heat exchanger is a third or more the cost of a new furnace. If you are concerned about the extra cost of a new furnace, ask your utility if it offers low-interest loans or other monetary incentives for installing a high efficiency unit.
If the problem is something less expensive than a new heat exchanger, get it fixed especially if you have a newer furnace. If the furnace is older than 10 years, however, start preparing for replacing it in the coming years especially if it is a lower efficiency model. You will have plenty of time to set aside money for a new unit or obtain low-cost financing.
Get a second opinion from a reputable HVAC contractor if you have any doubts about being red-tagged and obtain an estimate of repairs from them. When you call, let them know it is a red tag situation that requires an assessment right away. A third estimate is not a bad idea either. If contractors know you are shopping around, they are more likely to offer their best deals early in the discussion.
Once that red tag is history, arrange with your HVAC contractor to obtain regular furnace maintenance at recommended intervals. If your heat exchanger was replaced but was not covered under the original furnace warranty, consider purchasing an extended warranty for the new heat exchanger. If you purchased a new furnace, you will start enjoying lower winter utility bills right away and probably quieter operation.