Central air conditioner installation: what to consider


Installation of central air conditioner involves many preparation steps that enable you to get optimal performance of the system. In this post we will outline the basic concerns for central air conditioner and its installation, so ask a contractor near you for solution appropriate in your case.

1. Choose the right-sized ac unit

Central ac installation is not a cheap project. Therefore, you need to do your due diligence to select the ac unit that has got right size for your premise. This step is crucial as it affects the conditions you will live in and your budget as well.

When it concerns central ac unit and its installation, size stands for the exact amount of heat the unit can remove out of your home. 
In other words, it stands for ac unit capacity. You can measure air conditioner capacity in one of two metrics:
  • British thermal unit (Btu) per hour
  • Tonnage
However, in the UK we usually express capacity in Btu metric. So, let’s discuss this metric in more details. Btu is about energy (heat) you need to use to raise the water temperature at certain extent in an hour. One Btu means you take 1 pound of water and heat it by 1° Fahrenheit. That is to say, one Btu is equal to approximately 1.055 kilo joules.

Problems with undersized unit

If your install air conditioner of less capacity you really need, you will suffer from tree main problems:
  • Longer cooling period
  • Higher repair bills
  • Higher electrical bills
First, an undersized unit takes more time to cool your facilities or fails to do it at all. Second, longer run leads to increased wear and tear and more frequent breakages. In other words, you will spend more money to repair your cooling appliance.

At last, you have to pay for wasted electricity. Let’s explain it with an example of far distance at the first sight. Imagine you want to boil water somewhere outside in cold winter with just one candle in your possession.

However, the candle can give less heat to the water that cold air takes away. As a result, you will spend (and waste) your candle but you will not boil your water. So it is with an undersized unit though situation is vice versa. Heat accumulates in your house more quickly and intensively than air conditioner is able to remove. 

Problems with oversized unit

In contrast, if you complete ac installation of too much capacity, your oversized unit will cool your rooms too fast to remove extra moisture. That is to say, your may have to face extra humidity in your house. In turn, it may affect your health and spoil your clothes, linen and furniture.

So, you will end again with more money to spend. Besides, a unit of higher capacity costs more. It means, you overpay for your cooling system at installation stage.

How to calculate the heat gain

Of course, you need to consider a lot of factors to calculate the heat gain. Nevertheless, the basic factors are the following:
  • Premise size
  • Heat sources
  • Insulation
  • Premise location
Premise size includes not only its length and width, bur its height as well. Speaking about heat sources, we mean total heat radiation of all appliances and the number of people living here. These two bullet points are easy to estimate.

However, premise insulation and location needs an expert to estimate their impact on the total heat gain. So, ask a reliable contractor about this when you design your central ac system.

2. Choose air conditioner with an optimal efficiency-price rate

AC efficiency is the ratio between its heat removal capacity and its electricity consumption. In other words, it shows the number of Btu per a watt. In the UK AC rating rated efficiency usually is expressed in letters. Efficiency of modern units typically varies from A to A+++. Installation of central air conditioner that has got higher ratio helps you to save money on your electricity bills.

Although units of higher efficiency are cheaper in use, they are more expensive to buy. Therefore, you need to consult with your budget whether you can afford it or not. We often recommend our clients to choose the appliance in the medium efficiency segment. This is because its efficiency-price ratio is optimal.

3. Think about installation of a multi-zone central air conditioning system

There are two main types of central air conditioning system:
  • One-zone ac system,
  • Multi-zone ac system.
One-zone central air conditioning system has only one thermostat to control the temperature in the premise. However, it may be very inconvenient to have all rooms at the same temperature. Moreover, recent researches proved lower temperature in your bedroom benefits you health and prevent your skin from early aging.
In contrast, with multi-zone system you can create two or more separate zones. To reach this you need to install additional thermostats for each zone and mechanical dampers.
Thermostats control temperature in each zone. In addition, mechanical dampers direct the air toward certain zone based on its cooling needs.
To summarise, it is worth noting you can save up to 30% on your electricity consumption if you install multi-zone central air conditioning system with right-sized unit of A++ efficiency. Isn’t it great to pay less for more comport in long run?