Dirty condenser coils increase energy costs. When the coil becomes clogged with dirt and grime, it’s unable to provide adequate heat transfer, a process that was predicated by the manufacturer on a clean coil. The equipment’s compressor senses this and tries to overcompensate by going to a higher system pressure. This consumes greater electricity. For example, a dirty coil could easily consume up to 37% more electricity as compared to a clean coil. That adds up quickly!
Take a look at a 10-ton air conditioning system operating for an average cooling season of 1,500 hours. When the coils are clean, it will cost approximately $1,650 to operate for the season, given a typical Kw/hr cost and equipment SEER (efficiency). However, when the condenser coil becomes dirty, the six-month cost of operation escalates to $2,230. That’s a 37% increase in cost.
By comparison, if the condenser coil on this unit were kept clean, a savings of $618 could be realized. That’s a savings of about $62 per ton. If you multiply your total building tonnage by $62, you can see what the savings would be. For example, in a typical residential setting, the homeowner could realize a savings in electricity cost of about $248 for the season for a 4-ton system.
When dirt and grime on the condenser coil restrict the transfer of heat, it causes the compressor to work harder. More heat is added to the system and the head pressure could rise by as much as 75%. This can result in a loss of cooling capacity of up to 30%. Your 10-ton system would now only provide 7 tons of cooling … at a higher energy cost. And typically when that happens, it happens on the hottest days of summer!