how to calculate diversity factor in VRV

[kamal12341]

Hi guys,I have a VRV system installed in my building but in summers I often get A/C complaints.I contacted daiken and they told me that the system has lived its life almost 9.5 years and also the diversity factor is quite high and we need to change are outdoor unit with a bigger capacity

I have 36 HP outdoor units for my 7 floors each.They are recommending to change it with 50 HP each .In this w ay they are saying that diversity factor which is 142 % will come down to 102 %..But how ???

[Loops]

Hi Kamal,

First : Life expectancy.
Most manufacturers will tell you about 15yr life expectancy depends on good install, ,correct maintenance and based on average office working hours (8hr day).

Second: Diversity.
Most manufacturers give 130% max as diversity factor.
What is diversity? Simply the ratio of all the indoor units output to the outdoor duty, so

If you have 142% diversity and 36HP outdoor unit duty you indoor loading is 36*1.42 = 51HP
So the SMALLEST outdoor you should have would be 51HP/130% = 40HP
But it always advisable to get to outdoor to match as close as possible to the indoor load.

You don't say if your VRF is 2-pipe or 3-pipe, personally I don't like seeing high diversity on 2-pipe systems, it's pointless.

Regards

Loops