currently we run 8 commercial ceiling mounted units. Problem is, if one or 2 break, we get complaints galore even though the ambient temperature is probably 24-25c.

 

Is it more economical to buy 1 big central unit? The individual units cost around 70k a piece and are getting between 5-8 years old.

 

Just looking for suggestions as I'm new to this.

 

Thank you in advance  

Here's a decent document to get you up to speed:

 

https://www.scribd.com/doc/18185824/HVAC-Design-Thumb-Rules

 

Let's move this topic over to the Electrical Sub forum.  Good luck!

 

Topic Moved.

if it is not an 'eating establishment' i would suggest you find other ways to increase moving air volume... ceiling fans, wall fans etc.

 

if your existing air con units can cope well with the space, you just need to increase circulation of air.

 

you can also do a combination of new a/c unit + fans... again this works great in most settings except mid end and above eateries where wind cools down food and drinks too quickly.

 

good luck!

Get a punkah wallah.

Can you provide more details of the actual building? Is it a warehouse style building? Commercial style like a large shop or is it a collection of offices?

Depending on what type of building there may be passive methods of reducing the initial heat uptake to reduce the actual amount of cooling energy required.

The idea of using A/C with Fan will be the best idea for you. 

 

The AC will only have to cool down the air while the fan will be circulating the cool air around. This way, you can reduce the number of A/C that you need at any one time as well as ensure the cool air is circulated around adequately.

 

You can use a small ceiling fan or some wall mounted fan to do the job..