Air Conditioning FAQs

Let us help with general air conditioning FAQs:

Why is the SIZE (rating of the air conditioner so important?

Efficient air conditioning units cycle on and off keeping the temperature controlled, humidty out and air clean in your home. If your air conditioner is not the correct size, the following may happen:

  • ​Too Small - The compressor will run 100% of the time, increasing running costs and machinery wear and tear. 
  • Too Large - The compressor will not turn on often enough to remove humidity from the room resulting in a damp, uncomfortable atmosphere. 

Electrical installation tips:

  • Any appliance over 10amp/2400watt requires a separate circuit - see your licensed electrical contractor
  • High starting current can caught lights to flicker. Problems that occur as a result of single phase air conditioning unit with compressors larger than 1.75HP or 1.3kW with starting currents greater than 45 amps can be rectified by fitting the compressor with a manufacturer's recommended starting device to limit current. 

What size system do I need?

Not only the size of the area that needs to be conditioned but also the amount of existing glazing (glass) and the heat load generated from the number of people occupying the area will determine the size (rating) of the system required. Thompson Cooling recommends a site visit by one of its sales consultants to determine the correct system sizing for your home or office. If a site inspection is not possible then floor plans will aid in the preparation of your quotation. 

How often should I clean my air conditioner's filter/s?

A general indication is when the filter ‘indicator’ light flashes – however it does really depend on the environment and/or the air purity. In a clean domestic situation once every season is normally adequate. In a commercial situation, once every month is mandatory. 

I've cleaned my air conditioner's filter/s but the light won't go off?

You will need to press the reset button. On wall mounted split and floor consoles systems you will need to remove the grille to find the reset button. With ducted, light commercial and commercial situations the reset button is normally on the controller. 

When I go on holidays, should I switch my air conditioner off at the power point/switch/isolator/fuse box?

It is OK to turn the power off, especially if you are away for long periods. Most units have a low wattage crankcase heater that keeps the compressor warm. If the compressor is cold, damage will occur at startup. If you turn off your air conditioner it must be turned on at least 12 hrs before use. 

I have a ducted air conditioning system but the air only comes out in part of the house?

Ducted systems can be designed so that only parts of the house (zones) can be air conditioned at a time. Check that the zone switch is turned on. 

During the heating cycle, a white mist is expelled from the outdoor fans?

During winter, most air conditioners defrost when the outdoor temperature is below 6°C. This mist is normal, it is only warm water vapour being expelled. 

What is Back-To-Back installation?

This applies to the installation of a ‘split’ system. If the installation is back-to-back, the indoor unit is positioned on the interior wall adjacent to the outdoor unit, reducing the length of the connecting (refrigeration) pipe-run between the two units. 

What is the operating cost?

The most energy efficient method of heating and/or cooling your home or office is reverse cycle air conditioning. Essentially, operating costs are determined by how long the air conditioning system is running and the size of the area to be cooled. It is essential that the correct size unit is installed. An undersized unit will be significantly more expensive to run taking longer to heat and cool the area effectively. 

What is an Inverter Air Conditioning System?

An Inverter system uses a variable speed compressor, which means that the cooling or heating capacity of the air conditioning system will be automatically varied to suit indoor conditions. This makes inverter systems more economical and efficient to operate as well as offering quieter operation than standard counterparts. These units will operate at a lower outdoor temperature and will bring the room to the correct temperature quicker. Inverter systems are available as wall mounted splits or ducted systems. 

What is the different between a room air conditioner and a split system air conditioner?

A room air conditioner is the more common form of air conditioning, where the compressor and fan are together in one box. These units are generally installed into a wall or a window. The split system air conditioner comprises of two units – the outdoor condenser and compressor, and the indoor unit which houses the evaporator fan. These units are connected by refrigeration pipes. The design of a split system allows the unit to be very quiet, in operation, and generally more efficient on electricity use…. See our Daikin Split Systems

What benefits does a ducted air conditioning system have over a split system?

A ducted air conditioning system is designed to air condition more than one room within your home. The indoor fan coil unit is situated manually in the ceiling space and is connected to the outdoor condensing unit. Individual outlets are situated in each room with the air conditioning controlled by a central controller. Unlike the ducted system, the split system is primarily designed to air condition only one room. If you are looking for an even flow with air conditioning throughout the entire home, our air conditioning installers recommend a ducted system….. See our Daikin Ducted Systems

What size unit is required for my house?

This is one of the more challenging questions to answer without sighting plans of your house. A sight visit by a qualified air conditioning technician is typically required. The size of the air conditioner is determined by several factors (i.e.) the size or the area to air condition, the aspect of the premises, large amounts of glass and the heat load generated from the number of people (as in the case of a restaurant) or the number of computers and so on. 145 watts per square meter is required to provide year round comfort conditions, as a general rule… See our Sizing Plan.  

What is meant by zoning for a ducted air conditioning system?

Zoning allows you to control air conditioning in different rooms of your home. Allowing you to heat or cool certain sections of your house at will. This is done through the use of zone controls in the ductwork in the ceiling space. (e.g.) a two-storey house may have an upstairs and downstairs zone, commonly called a day night zone. A larger house may have four or five zones, and depending on the size of the air conditioning, there may be a restriction to how many zones can operate at any one time… Read More  

How are the air conditioning units controlled?

Some air conditioning systems are controlled manually, others by infra-red remote control. Split systems, for example, have an infra-red remote control with functions to control temperature settings, timers and humidity levels. Ducted systems are controlled generally through a centrally located wall mounted controller. This unit controls temperature settings, fan speeds, humidity levels and timer functions. 

How much does it cost to run?

Reverse cycle air conditioning is considered a more energy efficient method of heating or cooling your home. Running costs are influenced by how long the air conditioning unit is left to run. In this way, an undersized air conditioning system will be significantly more expensive to operate than one that is correctly selected. At a cost ‘tariff’ of electricity of 26.7 cents per kw hour, an average two horse power unit with 1.4 kw power input, would cost approximately 38 cents per hour running non-stop. NOTE:- a number of Electricity Authorities do offer reduced ‘tariff rates’ and or ‘control systems’ in relation to air conditioning. This highlights the importance of working with a qualified and experienced air conditioning company. 

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As business owners Tracee and I understand the challenges of the day to day running of a business. We must compliment you and your crew in the way you conduct your business, from the moment we made contact, to the installation on the unit, all was seamless.
You showed up when you said you would for the quotation, you were prompt in getting a quote to us, Matt was extremely helpful and knowledgeable. The guys you sent to install were thoroughly professional and are more than worthy of the title of tradesmen.
I know two of the men are apprentices, as a tradesman myself I fully appreciate and understand what to look for in apprentices and I saw the makings of good tradesmen in those guys.
The unit is quieter than Matt said it would be, which was my only concern on the placement of the unit.
Well done to all involved and to you as business owners,

Many thanks , Paul and Tracee

Ps Your competition sucks, we have had the "its too hot to get in the ceiling at this time of the year" to non-return of phone calls, and we are too busy doing tenders spiel.

Paul and Tracee 20/03/2017

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