Common Mistakes to Avoid During Air Conditioning Installation

Getting air conditioning fitted in your home is a significant investment, and when it goes well, it can transform how comfortable your property feels throughout the year. But when the process isn’t managed properly, common mistakes can lead to poor performance, unnecessary energy use, premature breakdowns and even safety risks.

Whether you’re researching your first system or replacing an older one, understanding what can go wrong is just as valuable as knowing what to look for in a good installation.

If you want peace of mind from the outset, speak to an expert at GLP Air Conditioning before making any decisions.

Is Choosing the Wrong System Size a Common Problem?

It is, and it’s one of the most consequential mistakes made during domestic air conditioning projects. Fitting a unit that’s too small for a room means it will run constantly without ever reaching the desired temperature. Fitting one that’s oversized causes it to cycle on and off too frequently, wearing out components faster and leaving humidity levels uncomfortable.

Correctly sizing a system requires a proper heat load calculation, which takes into account the room’s dimensions, glazing, insulation, orientation and how the space is used. A reputable installer will carry out this assessment before recommending any system. If a company skips this step and simply asks how big your room is, that’s a warning sign worth heeding.

Poorly Planned Pipework and Unit Positioning

Where the indoor and outdoor units are placed has a direct effect on performance, aesthetics and long-term reliability. Outdoor units need adequate clearance for airflow and should not be positioned in enclosed spaces or against walls that restrict ventilation. Indoor units need to be positioned to distribute air evenly across the room, not simply mounted wherever is most convenient for the fitter.

Poorly routed pipework is another common issue. Pipes that run across visible surfaces, are left uninsulated or take unnecessarily long routes, can create energy losses and look unsightly. GLP Air Conditioning prioritises concealed pipework and clean routing as a core part of every fitting, not an optional extra.

What Happens When Electrical Work Is Not Done Properly?

This is an area where shortcuts can create serious safety risks. Air conditioning systems require a dedicated electrical supply, correct protection devices and proper earthing. Many installers subcontract the electrical element to a third-party electrician, which can lead to miscommunication, delays and inconsistent quality.

GLP Air Conditioning carries out all electrical works in-house, meaning the mechanical and electrical elements of every fitting are designed and delivered as a complete package. Everything is tested, commissioned and documented to the correct standard, removing a common point of failure that affects many domestic air conditioning projects across Essex and beyond.

Installation Mistakes to Watch Out For

Here’s a clear overview of the most common installation errors and what they typically result in:

Common Mistake	What Goes Wrong	How to Avoid It
Incorrect system sizing	Poor cooling or heating, excessive running costs	Insist on a proper heat load survey
Poor unit positioning	Uneven temperatures and restricted airflow	Use a design-led installation approach
Subcontracted electrical work	Safety risks and inconsistent workmanship	Choose an installer with in-house electricians
No pressure testing	Refrigerant leaks and early system failure	Ensure full commissioning and testing is included
Inadequate pipe insulation	Energy loss and condensation issues	Confirm proper insulation standards are followed
Skipping the handover	Incorrect usage and avoidable faults	Request a full system demonstration and walkthrough

Skipping Commissioning and Handover

Commissioning is the process of checking that a newly fitted system is operating correctly, refrigerant pressures are within specification, and all electrical connections are functioning as they should. Some fitters treat this as optional. It isn’t.

A thorough handover should also be part of every fitting. You should leave the process knowing how to operate your system, set schedules, use smart controls if included and understand what maintenance is required. If your installer doesn’t offer a proper demonstration on completion, ask for one.

Speak to an expert at GLP Air Conditioning to learn how a fully managed installation process works from survey to handover.