Hi,

First time on here so hopeful for some help.

I am the UK Sales Manager for a coil supplier based in Italy.

We have supplied 4 condenser coils 2-OFF 'V' unit chillers. The enquiry from our client was as below:

The operating conditions are:

Refrigerant: R407c
Air Temp: 30C
Condensing Temp: 50C (Dew Point)
Heat Rejected: 90kw
Air Flow: 7.5m3/s

We have designed the coils around these conditions, the selection shows a condensing pressure of 19.83 bar (a) and a maximim allowable pressure of 21 bar. This is in line with PED 97/23/CE Classification Class 1.

The selection was approved by the client.

The client is now rejecting the coils as he says the condensing pressure will be higher at start up when the water is above 12C. Also the coils will get dirty again rasing the condensing temp and pressure.

I believe we could only design the coil around the information supplied, it is down to the system designer to advised higher pressures etc.

Am I right?