A good Design?

[Servicefrigo]

Hy all

After your opinion which is the best cheapper and most modern solution for the next data;

6.freezer rooms x with a total surface 4000 m3 /-22 *C
The rooms are for store frozen products To -17*C
The customer must have the right to use these coldrooms ,for keep refrigerating products if he whant .
To +4*C
Monitoring and heat echangers are required also

Regards

[TXiceman]

You are looking to operate the over a fairly wide temperature range. You will need to balance your condensing unit and unit colers at both conditions. The problems you will encounter are:
TXV operation and sizing
DX distributor sizing and coil circuiting.

I regularly design rooms to operate over a range of temperatures, but the wider the range the more problems you will have.

I'd suggest you hire a loacal engineer capable of studying the design.

Ken

[US Iceman]

If you use semi-hermetic or hermetic compressors you will need to verify the compressor selection for both extreme operating conditions (lower and higher evaporating temperatures).

The motors may not be capable of sustaining the operating condition for one or the other of the operating conditions.

The condensers will have to be selected for the highest heat rejection capacity.

This is not an application that may work with prefabricated condensing units. At least, I don't think it will as a first estimate. You may have to resort to using an engineered approach with a remote condenser, multiple compressors (with oil recovery system), and suitable sized evaporators and TXV's.

...but the wider the range the more problems you will have.

I agree. This should be carefully reviewed to make sure the system works correctly for a long time.