How to Extend a Portable Air Conditioner Hose

A portable air conditioning unit is set up with the hose venting out a window.
What You'll Need
Length of high-quality flex hose

If you need to cool down a room, but have no convenient way to vent your cooling unit, you may want to know how to extend a portable air conditioner hose to vent over a larger distance than what is provided for by your existing hose. Before you continue with this project, it is important to understand that there are various pitfalls to extending the hose of your portable air conditioning unit, but in some cases, you will have no other option except to do it yourself. If this is the case, the steps below will provide you with the proper procedure for doing so.

Step 1 – Understand Your Portable Air Conditioning Unit

Unlike window air conditioners or other types of air conditioners that are at least partially outside, portable air conditioning units will typically be positioned entirely within one room of your house. These units work by sucking warm air out of the room and then venting it outside. If your portable air conditioning unit is not able to vent this warm air outside because of the hose, the unit will not be able to cool down your home effectively.

Step 2 - Precautions

Before making the decision to extend the length of your unit's exhaust hose, it will be important to fully understand the potential pitfalls of this project. Portable air conditioning units typically come standard with five-foot to seven-foot exhaust hoses, which is the length that most units are designed to push air. Extending the length of your exhaust hose can potentially cause problems with back pressure and it can make your portable air conditioning unit run less efficiently or even break the unit completely.

Before extending the length of your exhaust hose, carefully read through your unit's warranty to see what will occur if your unit is damaged in this way. In many cases, extending the length of your portable air conditioning unit's exhaust hose will void the warranty of that unit and leave you without recourse if your unit breaks.

Step 3 - Increase Diameter of Exhaust Hose

The most important thing that must be remembered when increasing the length of your exhaust hose is that you need to avoid creating back pressure at all costs. The best way to do this is to steadily increase the diameter of the exhaust hose as you move away from the unit itself. At a hardware store, you should be able to find lengths of flex hose of different diameters and connectors for connecting these lengths to one another. If you do have to extend the length of your exhaust hose, just be sure to never extend the length to more than 12 feet, as anything more than this will almost certainly damage your air conditioning unit.