What type of air conditioning is around these days?

One of the most common solutions for office cooling is air conditioning. This most often uses an outside unit called a condenser and an indoor unit called an evaporator.

In the past this was cooling only.

Then the reverse cycle air conditioner became available which allows both heating and cooling to be done via a wall mounted air conditioner.

The reverse cycle in turn can be further differentiated into the two pipe or three pipe reverse cycle air conditioner. The three pipe system is known by various names including VRF or VRV depending on manufacturer.

In terms of cost of installation a two pipe system is always cheaper than 3 pipe. Typically for domestic and small office installations the two pipe system most often provides best value to cost.

In terms of functionality the three pipe system provides more capacity and can be more efficient in mixed temperatures or where part of a building is in shade and part in full sunshine. The reason for this is because the three pipe heat pump system can use the heat from the hot side and use it to cool the cold side. This is achieved by having a collection point between the internal and external unit which can redirect gas and liquid prior to sending it to the external unit.

One of the effects of all gas to liquid air conditioners is the instantaneous effect of both heating and cooling. This can be lovely but can also cause discomfort. Air conditioners struggle to temper the cooling or heating effect that they provide. If you have a person who is sensitive to small changes in temperature (If the pick up of changes in increments less than +-2 degrees) then an air conditioned air can feel either too hot or too cold.

One way to modulate this effect is by fan speed. If an air conditioner is chasing a target temperature it can slow down fan speed as it approaches the target temperature.

Chilled water based air conditioning is generally subtler with the delivery of air and the overshooting of a target temperature is less pronounced. However chilled water systems require a far larger level of complexity and therefore capital investment and infrastructure. However from a power consumption point of view chilled water systems can be more energy efficient per unit of cooling delivered for larger projects.