It’s winter and you have started noticing you air conditioner is doing some strange things. Read below to see what your air conditioner can do in the winter months to help keep you warm inside.
Water Pooling Around the Outdoor Unit
It is ok, this is normal and your unit is designed to do exactly this.
During heating operation, the outdoor unit will produce condensation. If there is no drain installed to remove the condensation away from the unit, water may build up around the outdoor unit.
If you prefer to have the water drained to another location, please contact your installer who can arrange this for you.
It is perfectly normal for the outdoor unit to produce condensation in heating mode and is not a unit fault.
When I turn on the air conditioner it takes up to 5 mins to start blowing warm air
Due to the cold, the outdoor unit needs to warm up before it can start blowing warm air out of the indoor unit. The air conditioners are very much like the car heater with the engine needing to warm up before the heat comes thru the vents.
Depending on the temperature it also maybe going into defrost mode as well.
Air Conditioner going into Defrost Mode
Defrost function is a feature on every air conditioner and is designed to remove the ice build-up on the outdoor unit heat exchanger. Ice build-up on the outdoor coil occurs during the heating process of the air conditioner because the temperature of the outdoor coils drops below zero degrees causing the moisture on the coil to freeze.
Why does it need to happen?
If a heat exchanger is covered in ice, the airflow is restricted and therefore the efficiency of the heat exchanger is greatly decreased. Ice on the heat exchanger also acts as a thermal insulation barrier preventing heat absorption which would reduce the unit’s capacity to heat and eventually cause it to stop. By defrosting the heat exchanger the efficiency is increased.
How can I tell if my unit is defrosting?
Most units will indicate defrost by flashing LEDs on the front cover. This may be a red or green LED depending on the model. Other units that have a wall controller will display a defrost icon.
How often does it need to happen?
This really depends on the following factors:
- How cold/damp is the air around the outdoor unit
- How much work the unit is required to do, e.g. room insulation, thermostat setting is too high or greater expectation to heat adjacent areas
- Are there any mechanical defects with the unit?
- Is the unit sized correctly?
- Are the filters and condenser clean?
- Is the outside unit recirculating its discharge air?
Assuming for now there are no mechanical defects…how often would my unit be expected to defrost?
Most units will not check for a defrost requirement until at least 45 minutes have elapsed from the initial start-up. This period should have given enough time to bring the room to the desired temperature (assuming you have set a realistic and achievable temperature setting).
After defrost has started, how long should it take to complete?
Defrosting function on most units is ended after a certain time has elapsed OR the outdoor unit heat exchanger temperature has risen sufficiently indicating that defrosting can be completed. Defrost termination can occur within 15 minutes.
If my unit is frequently defrosting… what could be wrong?
Regular and unsuccessful attempts to defrost an outdoor unit can be a sign that the system is undersized for the area to be heated. Or possibly you have set the thermostat to an unrealistically high setting.
Another factor may be that the unit could have a mechanical defect or suffer from a lack of maintenance. Refrigerant loss, heat exchangers blocked by dirt, restricted airflow due to obstruction such as foliage, blocked filters, or uncalibrated sensors are all possible problems. First, try cleaning the air intake filters to the indoor unit as this may help to reduce the frequency of defrost and will help improve product performance.
Also, check your unit is not set to a fixed low fan speed as this will prevent the unit from delivering full heat capacity while it can. Adjust the fan speed to ‘auto fan’ as this allows the unit to automatically adjust the fan speed so the output capacity will match the requirement. If the unit is the correct size and the thermostat setting is realistic, the fan will slow as the temperature rises. Turn the heating on earlier or leave it on in extremely cold conditions.
If none of this helps we advise a visit by an air conditioning specialist to help diagnose the problem.
Is there anything I can do to decrease defrosting?
Your air conditioner will need to defrost if the ambient temperatures are low. Keeping the doors and curtains closed will help; Insulate your floors and ceiling if they aren’t already. Only set your thermostat to a maximum of 21 Degrees Celsius and try and reduce the load by closing off zones that aren’t being used.
This is usually high enough for comfort levels and most sizing calculations would be based on this. Thermostat settings higher than this will just cause your air conditioner to work much harder, defrost more frequently, and ultimately cost more to run.
^Answers are deliberately non-technical and do not cover specifics on any particular model, therefore some small allowances should be made for minor technical differences between units that can affect the way defrost is both initiated and then terminated.
