This article is written from the point of view of a commercial or semi-industrial installation using fluorinated gases in direct expansion. We are not talking about large industrial facilities, facilities which use ammonia and similar where this is not even an issue. In large facilities there is always a technical project, so it tends to be the engineering department which is responsible for selecting and designing the best installation with the means available, taking into account the considerations of the premises.
In small and medium-sized installations, the design is normally carried out by the installer, who recommends the assembly of one type of installation or another.
Let's break this down.
What is a refrigeration plant?
A refrigeration plant is a group of compressors that work in parallel mode adding the individual input of each of the compressors making up the plant together. Most of the English documentation talks about compressors in parallel (parallel compounding or parallel circuits)
Why a refrigeration plant?
There are several reasons for using central rather than individual compressors (we can also give reasons why we should use individual compressors instead of a cold store).
Some of these are as follows:
●Physical space in the engine room
Suppose we have a typical installation of a supermarket or medium-sized refrigeration plant with several cold services in the same temperature range.
The "normal" solutions would be:
1.Condensing units or condensing group: Installing as many condensing units as there are services or cold points
2.Compression units refer to a special type ofcondensing unitwhere on the one hand you have a compressor mounted on, or with the liquids container and its controls, and on the other hand you have the condenser
3.A multi-circuit compressor is a grouping of compression groups in a bank with one or more external condensers common to all groups. The capacitors are internally divided into as many circuits as there are compression groups.
4.Single-suction refrigeration plants, for joint work at the same evaporation temperature.
5.Multi-suction refrigeration plants are several refrigeration plants connected by the suction manifold to be able to work at different evaporation temperatures. They work on the same container and condenser. It’s like the central of the centrals.
6.Tandem compressors (erroneously called cold storage plants) are the simplest cold storage plant installation where 2 compressors are physically linked and work together as a central unit, but without the independence of the compressors.
Advantages and disadvantages of each system
Therefore, there are basically 3 main types of installation and each type of installation has its advantages and drawbacks
Complete independence of each of the systems
Large space in engine room, inefficient system
The same as with condensing units, and there is a certain reduction in space in the machine room due to the use of a common condenser.
Efficiency, reliability, duration, and reduction of space in the machine room
If there is a refrigerant leak, the repair may be more expensive