In my previous blog, we looked at the benefits of air conditioning on education. In this one we explore which units are suitable for the wide variety of educational buildings.
In general, the choice depends on the age of the building, the number of rooms being done at once and the use that the room is being put to. Remember, all modern air conditioning units use heat pumps to heat as well as cool.
New-build or major projects
The default option is a three-pipe VRF system with ventilation and heat recovery. This is a single large, but compact, unit on the outside of the building, which can serve up to 80 internal units.
VRF stands for variable refrigerant flow, which, unlike previous on/off equipment, uses an inverter to deliver exactly the right amount of cooling or heating wherever it is needed, which reduces costs and CO2 emissions.
This is particularly suitable for a new-build or projects involving multiple rooms, as it means the minimum of outside space is required to serve the maximum number of internal units. Even if there is no budget to do all the rooms you would like straight away, but you know you will be able to add more rooms in a reasonable time scale, it may still be advisable to install a large enough VRF system and add indoor units as required. VRF systems come in a range of kilowatt duties to suit any educational establishment.
Linking the system with ventilation means that, instead of just recirculating internal air, up to 10 changes of fresh air is supplied every hour; increasing oxygen and reducing CO2 levels, which improves concentration and performance.
However, once you have heated or cooled a room to the right temperature, the last thing you need is to pump out that optimal temperature air and suck in ambient air that may be at a vastly different temperature. Heat recovery uses heat exchangers to isolate the outside temperature from the inside as much as possible.
“Such a system will also allow free heating”
Such a system will also allow free heating. Even in the winter, strong sunlight through large windows can often heat up a south facing room beyond comfort. A three-pipe VRF system can take this free heat and move it to a north-facing room, where it is needed. A two-pipe system can heat or cool through all the indoor units. A three-pipe system can heat through some units while cooling through others.
The alternative is to use single or multi-split systems, which link one outdoor unit with between one and four indoor units. This is a viable alternative to VRF where only a few rooms are to be air conditioned. While smaller, these systems still heat and cool and, because they are inverter driven, can match power to required output.
“Single splits are particularly appropriate for IT rooms/suites”
Single splits are particularly appropriate for IT rooms/suites, where we usually recommend redundancy in the form of two independent split systems, so that if one should fail, the other has enough duty to maintain the equipment at the correct temperature.
Indoor units can be ducted, floor standing, high-wall mounted, ceiling mounted or cassettes. Cassettes are designed to recess into false ceilings, so are more suited to modern buildings. Ducted units, of course, require ducts to distribute the air, so are better installed in new-build or during major refurbishment. Their advantage is that the air distribution grilles are fitted flush with walls or ceilings, so there is no unit in the room. This is an advantage where space is a premium, or the unit may get damaged.
If you would like to talk these issue through, please contact me at………….
020 3376 3533