Fixing Intermittent Cold Air on a Central Air Conditioner

  • 1-2 hours
  • Beginner
  • 15-25
What You'll Need
Hose
Air filter
Wire brush
What You'll Need
Hose
Air filter
Wire brush

When your central air conditioner is not working properly, it can cause you to be irritable due to lack of cold air. Other times, you will have intermittent cold air; it is hard to say which one is worse. Fixing intermittent cold air on a central air conditioner is possible armed with the right knowledge and the right tools. This will allow you to enjoy your air conditioning once again.

Step 1 – Check The Outside Unit

Some models of air conditioners will include a pressure control in order to avoid damaging the condenser outside. A dirty condenser can cause the machine to protect itself from possibly being damaged. In order to allow your system to stop shutting off, you can simply clean the unit. In order to clean it, you will first need to turn it off. Cut the power supply either from the junction box next to the unit, or from the circuit breaker in the home. Use a hose with a sprayer attachment to spray out any dirt which may be in the finned coils. Make sure you are not using a high pressure washer as you may damage the unit instead of fixing it. Allow to dry before turning the unit back on.

Step 2 – Check The Air Filter

Many different problems can occur from a problem as simple as a dirty air filter. Depending on the filter you buy, you will need to replace your filter at least once every three months. Poorer quality air filters need to be replaced every month. When the air filter gets too dirty, it can inhibit the flow of air. The reason why you get bursts of air is when the machine turns on, it has a supply of air inside the unit. As this gets used up, it cannot draw new air, so instead it will draw in the recirculated air which does not have any cooling power.

Step 3 – Clean The Evaporator

A dirty evaporator will only allow intermittent success in cooling air because it will freeze over. As the unit works harder to cool the air, it will cause the evaporator to freeze over. When this happens, no hot air can be released from it. The only cold air you will get from it is right when you turn on the machine or as it goes through a cooling cycle. Use a wire brush in order to clean out anything on the outside of the evaporator coils. What you remove will look like gray fur.

Step 4 – Recharge Freon

Another problem you may be encountering is that you may be low on freon. This will cause you to get short bursts of cold air when the machine is able to squeeze out a little bit of freon from the unpressurized tank. In most states, the only way to get more freon is to call a service professional. The best way to know if you are able to buy your own is to go to the home improvement store. If they sell refrigerant, you can charge your own system.