- Posted by Air Conditioning Installers London
- On 21st February 2018
Air Conditioning Installation Commissioning
This article is the last in the line of a series of nine YouTube videos, and accompanying blogs, on how to install a ductless mini split air conditioner. Persons with DIY experience and those training in the HVAC industry should perform the guide, as detailed and straightforward as it has been presented. Furthermore, the tools required to complete, to fully install an air conditioning system. Won’t be found in any general home DIY store. If you need help with air-conditioning installation commissioning in London then contact us today!
Final Step: Air Conditioning Installation Commissioning
Commissioning comes after the pre-commissioning work is complete. In the pre-commissioning article and video, before this, all the checks are done to ensure the installation has been done correctly and is ready for a run test. The pipe connections are tested for strength, moisture and air removed from the lines and all electrics complete. Following steps 1-8 of our series, you are now ready to do a run test commission exercise. The process is very simple and requires, refrigerant gauges, a water bottle with water, a screw driver and thermometer.
- Turn on the system in the cooling mode using your remote control.
- The front louver will open and the fan will kick in shortly after you hear the beep.
- On every home air conditioner the remote will feature various symbols to indicate what mode it is in. The cooling mode is indicated by a frost symbol.
- Drop the temperature display as low as it can go, normally 16-18c.
- It will take a couple of minutes to start feeling cold air from the indoor unit.
This will indicate that the condenser has started and the refrigerant gas has started it cycle.
Air temperature readings
Take a recording of the current room temperature. Now take a reading of the air coming out of the indoor home ac unit. The air off the unit will gradually get cooler as the room temperature starts to drop. Look for a temperature difference of at least 10-15c cooler than the room temperature. This shows the refrigerant is fully charged and saturating the internal coil. Measure the temperature of the larger copper pipe coming out of the unit. Compare this with what the temperature reads on the low side gauge of the system. At this point you want to find the pipe temp is 5-7c warmer than what the gauges pressure/temp indicates. This is called the super heat reading and tells you that your residential air conditioning system is fully charged. Also condenser the air off will be 15c+ warmer than the ambient outdoor temp. Check this and with your hand feel the larger copper pipe at the condenser is cool and beginning to sweat.
Check the drainage
Always make sure the drainage lines and any condensate pumps are working. Gently pour water into the coil of the indoor unit. If you have a condensate pump connected then pour in water gently and gradually. The first time the condensate pumps starts on an air conditioning unit, you will hear a slight buzz where the pump is dry. The noise will stop and then you should see a continual flow of water coming out the pumped drain lines. Commercial air conditioning installation requires heavy-duty condensate pumps capable of high flow and high lifts of waste water. This is due to the increased capacity of these ac units generating greater amounts of condensate water. An air conditioner with a gravity fall drain needs to be checked also for no leaking fittings. Gravity fall drain can get air locks, which prevent the water draining away. To prevent this you should install an air break in the line by adding a tee piece of drainage with an up stand higher than the rest of the drain fall.
Now that you have confirmed the system is cooling and drainage in order, record your operating pressures. These pressures will be dependant on what refrigerant gas your comfort cooling system is running on. Domestic air conditioning systems in London will operate on a refrigerant called R410A. When your ac unit is in cooling look for a pressure reading of 7bar in operation. When the air conditioning system first turns on you may find, due to a high room temperature, pressure readings of 7-9bar. The pressure will stabilise and drop to 7bar as the room temperature falls. In heating mode, look for discharge pressures of 30bar+ on your discharge line at the condenser. The system works in reverse in heating so you will find the once cold suction line, is now a hot discharge line.
Experienced home air conditioning contractors will know to use gloves and goggles when working with refrigerant gases. Use a good set of gauges with quick release ports and shut off valves to minimise gas losses. Every time you attach gauges make sure on completion to pump the system down to clear the excess gas in the lines. Regulations in the UK say only Fgas qualified engineers can work with refrigerant gasses.
Log all information
Log all the air off temperatures in all modes. In this log, record any added refrigerant to the air conditioning system along with its pre-charged gas and all the pre-commissioning data. Every six months leak test all the connections and do an air conditioning service.
Watch our two part video of how to service a home air conditioner.
Thank you for following our basic how to guides on simple home air conditioner installation. We don’t not recommend persons without any DIY experience or the correct equipment perform this. This guide was written for tradesmen and trainees with the correct tools. DIY air conditioners come with all the pre made hosing, connections and a plug in power lead. These are the types of ac systems made for the general novice as there is no gas handling and everything is plug and play. Find these types of air conditioning units on line at your local DIY centres.
For help with fixed air conditioning installation commissioning in London email or call us today.