Jim Rooney On The Level

Q. My questions are home appliances and their longevity. Our oil fired forced air furnace is a thirty one years old Amana that has required very little maintenance. We’ve had it cleaned and adjusted yearly whether needed or not. On the last inspection the report showed the unit to functioning within the required parameters and no signs of structural malfunction. Our Carrier central air conditioner is approximately twenty years old and also continues to operate at peak performance.

Now may be the best time to stay ahead the inevitable malfunction of these units. My question is would it be feasible to have the furnace overhauled, replacing all of the heat producing parts and mechanisms?

Then replace the air conditioner with a more modern efficient heat pump to perform the dual purpose of cooling in the warmer months and as the primary heating in the cooler months and have the oil fired furnace as back up and operational on colder days.

A. I like the way you are thinking. When I encounter a system such as the one at your house I tell the homeowner or prospective buyer the good news is that it’s still working. Then I say the bad news is that it’s still working. It reminds me of one of my first automobiles. A real beauty. It was a 1954 DeSoto Fire Dome Eight four door sedan. Bought it for $25 and it wasn’t yet ten years old. Drove like a dream to the tune of eight miles to the gallon.

That’s your oil furnace. At age 31 not only wasn’t it designed to heat efficiently on today’s standards but I’m willing to wager that if you tore it completely apart you’d find weak and splitting welds in the heat exchanger signaling it’s time to go. The heat exchanger is a metal box inside the furnace that has burning oil and hot flue gases inside and has the blower pass the household air across its outside, heating the air for the house. The design is always that the blower pushes the air onto the heat exchanger keeping it under positive pressure rather than pulling air across it which could pull flue gasses out of those split welds and introduce carbon monoxide into the house. When the heat exchanger gets bad enough even the positive pressure doesn't help and service technicians can determine that and they will take the furnace out of service and then you have to replace it. You’ve been wise to have it looked at annually but as you correctly sense, the end is near. And like my finally getting rid of that old DeSoto for a more fuel efficient car, any modern replacement of that oil burner will be much more efficient than the old soldier you have now and with the price of fuel oil these days the reduced consumption will feel like a pay raise to you. When people think of fuel efficiency they think mostly of cars. But it’s buildings that use the majority of our fossil fuel consumption.

The other thing to consider when examining your system is the location of the oil tank. If it’s a buried tank, called an underground storage tank (UST), then just on its age alone I would either have it pulled out or filled with a gypsum slurry and abandoned in place. If it becomes obvious that it’s leaking, the clean up won’t be at your call but by others and can get quite costly. In some states, Massachusetts for example, you can’t sell a house with a buried oil tank.

Replacing your air system with a heat pump employing a fossil fuel furnace as a back up is called a dual-fuel system and for quite a while has been considered a state of the art configuration. Even if you just replaced the air-conditioning system alone you’d have to go to a system that is SEER 13 or better and that would probably require replacing every thing right down to the coils inside and the refrigerant lines leading from the outside unit to the inside-- in other words the whole shebang. The SEER rating of a unit is the cooling output in Btus during a typical cooling season divided by the total electric energy input in watt hours during the same period. The higher the unit's SEER rating the more energy efficient it is. A twenty year old air conditioning system might seem to cool just fine but it’s eating you out of house and home with electric bills.

The move towards energy efficiency at all levels has begun to make them more attractive to homeowners. I have read that geothermal systems have even been employed in some Habitat for Humanity homes where the lots were amenable to their installation. Ikea is installing a geothermal system in a new 450,000 sq. ft. building in Colorado and claims of efficiency are nothing short of astounding over traditional heating and cooling. They’d have to be. They are installing 130 500 ft. deep wells to supply the system.

You’ll need to get hold of an experienced heating and cooling contractor who is familiar with setting up dual fuel systems because the real trick is configuring controls and sensors. It’s not going to be cheap but the sooner you do it the sooner you’ll be able to reap the benefits of comfort and lowered heating and cooling costs. And you’ll wonder why you didn’t do it sooner.

Keep the mail coming. If you've got a question, tip, or comment let me know. Write "On The Level," c/o The Capital, P.O. Box 3407, Annapolis, MD 21403 or e-mail me at jimrooney@jimrooneyonthelevel.com or inspektor@aol.com.