Ability will be refitting their London Showroom. This is used to showcase and demonstrate its ranges of Fan Coil Units, Heat Recovery Units and Twin / Single Fan Units. It will also be used for training and CPDs. The facility itself is...

World Projects

Multi Room

What is a Multi Room Fan Coil?

A Multi Room unit, at its most basic level, is a conventional fan coil unit with a small but fundamental physical change overlaid with a unique, all new controlling strategy.

The physical change is something that Ability has introduced into its ranges and only Ability manufacture. The controlling strategy was wholly developed, written and tested by Ability and is only applied to Multi Room styled products.

The primary aim of Multi Room

Multi Room fan coils were designed to allow one larger fan coil to serve a number of small spaces or offices rather than, what would have normally been the case, to supply a small fan coil for each space.

The reason a number of smaller fan coils generally remains the only option is that to provide an acceptable level of individual control over each space demanded each space have its own small unit with its own controller and its own set point adjuster. The only alternative is to have a large fan coil serve a number of small rooms but with everyone having to accept either the average of the individual demands or the requirements of one space alone, invariably the office of the most senior employee. This averaging system is not really used in the UK because our temperature demands vary so much whereas, in Australia for example, the demand is nearly always cooling and to such a level the occupants don’t mind the small compromise providing they remain COOL!

So, at the highest level, how does Multi Room solve this problem?

A Multi Room fan coil unit is conventional ‘Draw Through’ fan coil using individual fan / motors but which has its discharge plenum specially sectioned. These sections are designed such that each fan / motor in the fan coil serves one plenum section alone – the section directly in front of it! This means that whatever each fan is doing, in terms of air volume, is delivered only to the plenum section in front of it and consequently only to the space that that plenum chamber is subsequently ducted to.

In this illustration of a three fan Multi Room fan coil you can see that the blue fan serves only the blue duct and therefore only the blue grille in let’s call it the blue room. Likewise, the green and the red fans would only serve the green and red rooms respectively.

Multi Room FCU

 

Obviously, and as the illustration shows the Multi Room units still only has one coil, one set of water control valves and one controller – so how does it provide individual control over each space in a way that a conventional unit cannot?

Well, a Multi Room fan coil has a conventional single return air sensor in the return air path but unconventionally there is a supply air sensor in each of the discharge plenum sections. Also, each space will have a room set point adjuster to allow each occupant to dial in his desired temperature.

Reading these various temperatures and considering the varying demands, the control strategy has to now make some decisions about what to do with the single set of control valves and the fan speeds of each fan – remember, each fan serves one space alone.

The Next Page on the Multi Room Strategy