Well, we have made it through a couple of really cold spells. But winter is really just beginning. The past few weeks, your home central heating systems have been overworking. When the temperature gets down below freezing for a long period, a central furnace will be running 80%-90% of the time. The big problem we have seen is, the home owners are over rating the throwaway air filters, which causes air flow reduction in your heating system.
The filters load up with dirt more quickly and need to be changed more often. When your air flow is reduced by 3-5% for a high rate filter, it gets dirty in a few weeks, and it has reduced as much as 10-20%. This makes the furnace overheat when running for a long period of time.
Filter ratings are by FPR or Merv. FPR are ratings for filters by the retailers, and Merv are ratings by the filter companies. FPR 10 or Merv 12-9 are better than most on the market, but must be changed every 10-15 days. FPR 9 or 7 and Merv 8 filters are rated better and changed monthly.
So if you’re using a high rating filter and your furnace is Short Cycle or not keeping up during the cold days or night, drop down to a lower FPR or Merv Rating filter.
Just remember, the filter is the heart of your heating system. Keep it clean and replace every 10-15 days.