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nevgee
26-10-2009, 10:03 PM
Hi guys,

I'm looking for a manufacturer /supplier of air cooled ac split or packed systems, which would be suitable for high ambient conditions. 50 - 52C onto condenser.

Ideally the systems should be suitable for high sensible cooling loads 5 /7.5/10/12.5kW and 50Hz electrical supply.

Any ideas?

cheeers

mad fridgie
27-10-2009, 01:37 AM
How many units, and has the client got plenty of cash?

Sridhar1312
27-10-2009, 12:50 PM
Instead of going for high ambient units it is better to add CELL DECK adiabatic pad with water spray on the pad which will ensure closer to the wet bulb temperature which will be less and it can save power too. Even the water spray can be set based on the ambient temperature say whenever the ambient goes above 35 degree C.
The above will ensure lower power and higher reliability

nevgee
28-10-2009, 11:16 PM
Instead of going for high ambient units it is better to add CELL DECK adiabatic pad with water spray on the pad which will ensure closer to the wet bulb temperature which will be less and it can save power too. Even the water spray can be set based on the ambient temperature say whenever the ambient goes above 35 degree C.
The above will ensure lower power and higher reliability


I realise this type of unit would be very suited as the location ambient air has low moisture content however. water for cooling purposes would be excluded as it would not be readily available.

mad fridgie
29-10-2009, 01:33 AM
What are the "air on" conditions to the evap?

nevgee
01-11-2009, 10:42 AM
What are the "air on" conditions to the evap?

Anything better than the ambient.

The space will be basic equipment rooms with some electronic gear in there. So, high sensible cooling requirement to maintain a "comfort condition". Temp and %RH is not critical say 25C. 50% for a starting point.

Looking for an off the shelf package system may be the wrong approach. Think I'll treat it as a high ambient chillroom and use commercial refrigeration kit instead.

mad fridgie
01-11-2009, 10:52 AM
Anything better than the ambient.

The space will be basic equipment rooms with some electronic gear in there. So, high sensible cooling requirement to maintain a "comfort condition". Temp and %RH is not critical say 25C. 50% for a starting point.

Looking for an off the shelf package system may be the wrong approach. Think I'll treat it as a high ambient chillroom and use commercial refrigeration kit instead.
Designed some systems working in conditions 20C to 60C ambient, also had single pass cooling, control was the difficult area.
In your case load sounds resonably constant, I would look a R134a should fit nicely into most compressor curves. Just need to allow for lower "air on" to the condensor. Fan speed and/or hed pressure control