WHAT DOES IT MEAN WHEN MY HEAT PUMP OR AIR CONDITIONER IS ICED-UP IN SUMMER?
It is never normal to see ice in the summer anywhere on a heat pump or a central air conditioner. This includes the indoor unit, outdoor unit and interconnecting line-set. It is possible to ice-up the indoor coil, however, if the air conditioner is running in very cold weather or if the thermostat is turned down extremely low. We recommend never turning the thermostat below 70 degrees. If air conditioning is needed during winter months, such as for restaurants or businesses, then a “low ambient kit” is required, and can be installed by a service technician. If you see ice anywhere on a heat pump or air conditioner during the summer, then there is most likely a problem and you should turn it off immediately. Below is a list of possible causes.
- Bad indoor fan motor – not running/running slow
- Loose, worn or broken fan belt
- Bad indoor fan relay
- Extremely dirty blower wheel
- Low refrigerant charge
- Blocked capillary tube
- Blocked orifice
- Faulty expansion valve
- Stuck compressor contactor
- Faulty thermostat
- Extremely dirty or damaged indoor coil
- Clogged or blocked air filter
- Supply and/or return vents blocked or closed
- Running air conditioner with windows open
- Setting thermostat too low
WHY DOES MY OUTDOOR UNIT MAKE STRANGE/LOUD NOISES?
Heat pumps do tend to makes strange and/or loud noises at times, more so in the winter. Heat pumps have reversing valves that reverse the flow of refrigerant between the heating and cooling modes.
- Bad motor
- Out of balanced or broken fan blades
- Low refrigerant charge – can cause “gurgling sounds”
- Bad reversing valve – passes refrigerant internally, makes “hissing sound”
- Buzzing contactor or noisy solenoid coil
- Loud compressor
- Loud unit
- Bad compressor valves
- Outdoor unit iced-up, fan blades hitting ice (weather-related)
- Fan blades hitting some other obstruction
- Vibration due to loose parts
- Vibration due to refrigerant piping being strapped too tightly
WHY WON’T MY OUTDOOR UNIT SHUT OFF WITHOUT THE USE OF THE CIRCUIT BREAKER?
This happens occasionally. The thermostat reaches the desired temperature, the indoor unit shuts off, the air stops blowing, but the outdoor unit keeps on running. In the heating mode (if it’s a heat pump), it could eventually shut off on a high-pressure safety device. But in the cooling mode, it could run forever unless you turn the breaker off. And this will cause the indoor coil to freeze up into a solid block of ice, and eventually the ice will build up and travel all the way to the outdoor unit.
So what causes this? Only a few things, the most common of which is a stuck compressor contactor – located in the outdoor unit. The contacts tend to get pitted-up. Eventually they can weld shut. This can cause serious damage to the system. It is good practice to replace the contactor every few years or when pitted – just like spark plugs in a car.
- Stuck compressor contactor
- Thermostat cable shorted
- Bad thermostat
HOW OFTEN SHOULD I HAVE MY EQUIPMENT SERVICED?
WHY SHOULD I HAVE MY EQUIPMENT SERVICED?
Annual servicing includes cleaning the system, checking for any problems or potential problems and adjusting for PEAK efficiency.
- Increased dependability
- Find potential problems and fix them quickly
- Provide maximum efficiency which lowers energy costs
- Prolongs the lifespan of the equipment
- Maintains safe and healthy operation
- Can help to protect the environment
- Drastically reduces the chance of a break-down, which usually happens at night or on weekends when repair rates are higher