Your Heating System and Common Problems





At this time of the year we get a lot of people calling in panic, saying things like…

  • “HELP! My outdoor ac unit is on fire!”
  • “A large puff of smoke came from the outdoor unit”
  • “My HVAC unit is making a loud grinding noise”
  • “There is water around my outside cooling unit”
  • “My heat is on and cold air is coming out the vents”

THANKS FOR THE CALL, but don’t worry, here’s an explanation of what’s actually happening:
When the outside temperature starts to drop and you switch to the Heat mode, your HVAC unit can do some things that are often alarming. While you outside condenser unit may appear to be smoking, gasping and taking its last breath, this is just actually part of the normal defrost cycle. This cycle is necessary for the unit to melt any ice that forms in the outdoor unit.

The defrost cycle happens in cold temperatures and usually only lasts for about 5 minutes. The unit will go into defrost cycle as needed, so no need to do anything. You may also notice water dripping off the condenser, this is just the melted ice so don’t panic. While in defrost you may hear noises often described as: clanking, humming, vibrating or thumping. Again this is normal for the defrost cycle.

If you experience any of this and you are maintaining the desired indoor temperature, you can relax knowing that your unit is behaving as it should. If you are not maintaining the desired temp, give us a call and we will be out to troubleshoot the problem.

Also normal but again a frequent cause for alarm is, “I turned on the heat and it smells funny.” In defrost cycle, the condenser will stop running, in order to maintain the desired temperature the heat strips will turn on and the system will run in “auxiliary heat” until the defrost cycle is over. This is very normal the first time you use your heat or if you haven’t used it in a while. Dust has accumulated over the year and what you smell is that dust being burned off.

A side note about the heat strips, on an extremely cold day they may turn on with the heat pump when the unit is NOT in defrost cycle to assist the heat pump in bringing the temperature up in your home.

When You Should Call Us:

  • If you notice the steam or ‘thumping noises’ last more than 15 minutes
  • If the condenser is covered in ice, and the unit has not gone into the defrost cycle
  • If the unit is not maintaining the desired temperature
  • The heat has been on all day and it still has a foul smell
  • Call Donovan Air, Electric & Plumbing 904-685-8355 We are available 24/7

Donovan Preferred Customer Maintenance Program: This provides all required upkeep to run your Jacksonville A/C system efficiently. With programs starting at $174 per year, you’ll gain peace of mind knowing that our licensed technicians are keeping close tabs on your heating and air conditioning twice a year.

Donovan Air Conditioning Repair: Few things are as annoying as an air-conditioning system that’s not working properly. When your system fails, you can rely on Donovan to correctly diagnose and repair your system fast.

Donovan’s 100% Guarantee:
Every Donovan purchase is backed by a 100% satisfaction guarantee. If you decide within one year of purchase that your complete system fails to meet or exceed your expectations, we will refund your money, no questions asked!

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