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Portable Aircon FAQ
  • How to portable air conditioners work?
    Portable ar conditioning units are all refrigerent devices and work on the same principle as installed split unit air conditioning systems that you see in offices and homes (a split system is one where you have an internal wall mounted unit connected by refrigerent pipework to an outside condensing unit that is usually bolted to a wall or on a roof). By using refrigerent the machine can produce chilled air very efficently. The air coming out of these machines is usually between 5 and 10C (40F and 50F).
  • What is the difference between a refrigerent device and an evaporative cooler?
    An evaporative cooler has a tank inside that the user fills with water. This soaks a rotating membrane. A fan pulls air through this membrane and as it does so the water evaporates off and it is this action that causes cooling of the air. Evaporative coolers require a constant supply of fresh, low humidity air in order to operate. This means keeping windows and doors open to allow constant fresh air change. They are largely ineffective here in the UK climate where we tend to get high humidity levels. We recommend you avoid evaporative coolers for this reason. Whatever the conditions a refrigerent air conditioner will always produce cooler dryer air.


  • What are BTU's and KW's?
    BTU's and KW's are different units of measure of heat (or cooling) energy. Here in the UK we always used to use British Thermal Units (BTU's) and often you will find heating and cooling equipment performance measured this way. On the continent they use the Internationally recognised unit of Kilowatts (KW). There is a direct relationship between the two - 1KW is the equivalent of about 3400BTU. So a 9000BTU machine is a 2.6KW machine.


  • How do I set up my portable air conditioning unit?
    To set up a portable air conditioning unit is simple. Having unboxed the unit you attach the flexible hot air hose outlet to the back of the unit and place the other end out of the room you are cooling. This is typically through a window or door. Then simply plug the machine into an normal 13A socket, switch on and that's it!


  • Do I have to have a hose?
    Yes. All refrigerent portable air conditioning units have to have a hose in order that the heat can escape. Do not confuse heat with humidity - with tumble driers you can place their hose into a condensing box but this is to remove moisture not heat. For an air conditioner you have to get the heat out of the room or it cannot cool it! The hose is typically 100-150mm in diameter (4-6") and is extendable from about 0.5 metre to 1.5-2.5 metre depending on the machine.


  • Where can I put the open end of the hose?
    The flexible hose has to be routed so the open end exits the room you are cooling. The obvious solution is to open a window and put the hose out through the window. The machines are supplied complete with an adaptor kit that reduces the amount the window has to be opend to only about 60mm. Alternatively the hose can be routed out through an open door, through a wall or even up into the ceiling providing the ceiling space is well ventilated.


  • Are portable air conditioners good dehumidifiers?
    All refrigerent air con units will remove moisture from the air as they cool it i.e. they dehumidify. This is an unavoidable effect of passing air over a cold surface to cool it (like the condensation that forms on a milk bottle when you take it out of the fridge). Whilst portable air conditioners are optimised for cooling performance they will dehumidify quite well. However, a portable air conditioner will only dehumidify within it's operating temperature range of typically 18-35C. Below this temperature the compressor does not start and the machine will not operate. A dedicated dehumidifier will be more efficent in operation (i.e use less energy) and can be made to work at temperatures right down to below freezing point.


  • What happens to the dehumidified water that the machine collects?
    The water that collects in the portable air conditioner as it dehumidifies is dealt with one of three ways. Some machines have a tank built in to collect the water with a float switch to turn the machine off when the tank is full. The tank is then simply removed, the water tipped away and the tank replaced. The most common method these days is to re-evapourate the water up the hot air hose automatically (known as self evapourating) so there are no tanks to empty and warm moist air is expelled up the pipe. The third alternative is to have a machine with a condensate pump built in. These machines pump the water away continuously via a thin secondary pipe that dribbles the water away. This pipe can be placed to run outside with the main hot air hose or can be routed up and into a sink or container. This can be useful where you cannot allow moisture to be vented though the main hose and yet you don't want the machine to stop when the tank is full.


  • What maintenance is required?
    Generally very little. The machines have a coarse air filter on the back which periodically needs a clean but other than that no regular maintenance is needed.


  • How long do they last?
    Difficult one! Expect about 5-10 years life from these machines. Failures are eventually from either a leak of refrigerent or from failure of a fan motor.


  • What is the warranty?
    All our machines are supplied with a 12 months 'return to base' warranty. This means that if you have a problem within the first 12 months we will uplift the machine from you on courier, repair or replace it and return it to you all at our expense. For this reason we reccommend you try to keep the original packing materials wherever possible to minimise the risk of damage by the couriers should the machine need to be returned.


  • Do you offer an extended warranty?
    These days all the machines we sell are generally very reliable. We at Dry-it-Out do not believe in taking money from people for extended warranties where it is unlikely they will benefit. So, we don't offer an extended warranty but we DO offer a complete post warranty service facility and we will NOT charge a customer a penny until they have agreed costs.


  • How soon can you deliver to me if I order?
    If the machine is marked as in stock then provided we receive your order by 4pm delivery will be by courier the following working day between 9am and 5pm. (In reality we can often still despatch for next day delivery right up to 5pm or even 6pm depending on when the courier collects!) You can optionally specify a timed delivery for pre 12 noon, pre 10am or Saturday by 12 noon at additional cost. You can also nominate a specific date for delivery if next day is unsuitable.