Important things to consider before accepting a refrigeration quote.

1

The ambient is vital when designing a refrigeration system.

Make sure the contractor has selected the correct temperature.

By designing for a lower ambient the system will be operating under extreme conditions during the hotter periods in Summer.

This will cause latent damage to the compressors and will eventually lead to system failure.

2

Make sure you are being offered semi-hermetic compressors. They are more expensive but last much longer than other types.

The condenser fans size and speed must be specified. Where ever possible the fans must be speed controlled, this will take care of most noise pollution problems and has better control over the high pressure conditions in the system.

The refrigeration plant room must be air-conditioned and maintained at a temperature of 26º c maximum. By doing so the plant will always be clean and dust free as well as controlling the temperature of the electrical switch boards.

Heat and dust are major contributors to electrical switch gear failure. The 15% diversification factor is used but should not be exceeded 25%. Using a diversification is common practice and should only be used on the medium temperature systems. The low temperature system must be selected at 100% load. Generally, the design should be for either one or two medium temperature units and one low temperature unit, this will also depend on the size of the store. Using multiplex systems is also a big energy saver.

3

Check that the capacity offered matches or exceeds the capacity in columns A and B (No. 8).

Also check that the Operating Temperature is correct.

6

Check that the condensing temperature does not exceed 42ºc.

Make sure the Kw given are greater than the Kw required.

4

Check that the condensing temperature does not exceed 45ºc.

Make sure the Kw given are greater than the Kw required.

7

The type, model, capacity and quantity of the evaporator coils must be detailed in this column for comparison purposes.

5

Check that the capacity offered matches or exceeds the capacity in column C (No. 8a).

Also check that the Operating Temperature is correct.

8

The final capacity required for each system relates to the figure in No. 3 and No. 3a for the two medium temperature systems.

The low temperature capacity relates to No.5.

9

The EPR valve plays a vital role in temperature sensitive areas such as Bakery, Fruit & vegetable, Butchery and drop temperature areas.

The EPR allows these areas to operate at higher conditions than the main system design.

This improves the quality of the products and saves huge amounts of energy. Butchery cold rooms benefit greatly where less moisture will be extracted from the meat and the dehydration process is inhibited.

10

This relates to the defrost required and is controlled via a timer or an electronic controller to activate heaters to melt any ice buildup on the evaporator coils in the cooling or freezing applications.

This is an extract from a sample report about the important things to consider before accepting a refrigeration quote.

Click Here to Leave a Comment Below

Leave a Comment: