Combustion Analysis, Furnace or Boiler analysis and Tune Up (Part 4 Home Energy)
A combustion analysis can be done on Oil and Gas systems to determine efficiency, draft, CO, O2, among other things. Typically the 80% efficiency + systems and below will progressively lose efficiency after they have been tuned. It is a good idea to have your system professionally maintained. It really does make a big difference.
Oil boilers and furnaces:
The best systems are typically 85% efficient. If you have an older system, it could be around 60% or 70% efficient. If you have an older system, it is recommended to discuss replacement with your HVAC professional. If no natural gas is available and you have the funds, switching to a geothermal heat pump is a great way to go. It is on the pricey side, with systems for 20-30K, but paybacks can approach 10%, depending on how much oil you are using.
Gas Furnaces or Boilers:
Natural gas is inexpensive in 2012, and the high efficiency 95% + units are affordable and extremely efficient. This is a nice option if you have a natural gas line that you can tap into. If you have an older 70%+ unit, a high efficiency replacement unit can give you a 10-15% payback, and with the sealed combustion, CO is no longer a major concern.
Electric Resistance Heat:
This is by far the most expensive way to heat a house. It is a great idea to switch to natural gas if you have access to a gas line, or to geothermal if you have the funds. High-efficiency natural gas units can yield a 20% ROI, while a geothermal heat pump can yield a 10% ROI.
Size really does matter: One problem in almost every home is that the heating systems are oversized. Does your system frequently turn on and off? Or does it run constantly? A perfectly sized system will run constantly on a cold day. A perfectly sized system will not be able to heat your house to 72 degrees on the coldest day of the year. Combustion heating systems run at their maximum efficiency at steady state. When a system starts and stops, it runs at a much lower efficiency than the unit’s rated efficiency. Fantastic savings can be gained by air sealing and insulating, thereby reducing the heating load on a home, and then the heating system can be replaced with a smaller, more efficient system.
ROI on heating system replacements: 7%-25%
(Varies dependent on how inefficient the current system is what fuel source, rebates, and cost.)
ROI on tune up for combustion equipment: 50%
(Possibly more depending on how out-of-tune your equipment is.)