How to Retrofit a Gas Furnace
Natural Gas Furnace Retrofit
An old gas furnace that has poor efficiency ratings can cost you a bundle. While it’s possible to simply replace the gas furnace, you can also retrofit it with some of the following upgrades that will save you money and improve its efficiency without costing you a fortune.
- Vent Dampers, When the furnace isn’t firing, a vent damper will close off the vent to stop excess chimney losses. These are most effective with older furnaces and boilers. Newer models don’t benefit much from this upgrade as they may already have features installed that provide the same basic benefit.
- Derating Gas Burners, The vast majority of older furnaces and boilers are oversized, resulting in too much gas being burned. It is possible, through retrofitting, to actually reduce the heating capacity of your gas boiler to the point that it only produces what your home needs based on an accurate load calculation. This is done by reducing the size of things like the baffles, the burner orifice and other components in your furnace. Beware that this is not allowed in all municipalities and must be performed by a professional due to local building codes.
- Intermittent Ignition, Instead of a continuous pilot light that burns all year round, you can have an intermittent ignition installed that will click on only when you need the furnace to operate. These are electric and quite complex so they should be installed only by a trained professional, but they are relatively low cost and they pay for themselves in 5-10 years. Keep in mind that the cost savings are more for devices that are not too old, older devices that can just be turned off entirely (pilot and switches) when not in use won’t gain much from this upgrade.
Retrofitting or Replacing a Gas Furnace
To decide whether retrofitting is worthwhile for your gas furnace, you must first determine the savings you stand to gain from doing so. If you feel like you’re going to gain a significant amount of money from retrofitting your gas furnace, you should contact a technician to go over your options. If some upgrades are not possible or you simply have a very old furnace, replacement may be your best bet.