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Le spécialiste de la climatisation
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Information and precautions

for water-cooled condensing units

Water-cooled condensation is used for our FW, CMHE, CMCE and CMVE ranges. It can be used with either loop water or water from or city water. A number of precautions must be taken to ensure the proper operation of a water-cooled condensing system.

Reversible / Heating models

The FW, CMHE and CMCE ranges include cooling-only and reversible models. In heating mode, heat is extracted from the water flow and transferred to the air in the room.

Please note that reversible models can only be used on a closed water loop.

The flow of water must be guaranteed to avoid any risk of the unit’s plate heat exchanger freezing and the resulting breakage.

When there is no water loop and it is not possible to install a reversible unit, you can resort to auxiliary heating using electric resistors. This option is available for cassette and ductable indoor units, as well as CMHE and CMCE monoblocs.

Safety and protection

For reasons of safety and equipment protection, our water-cooled condensing units feature the following safety features.

Specific maintenance

When using mains water, it is advisable to periodically check that the pressostatic valve is operating correctly, to prevent malfunction caused by limescale deposits.

Water quality

Water quality must be compatible with use in a water-cooled condensing unit. In the event of impure water, we recommend the use of a PN16 stainless steel strainer (see accessories). For very hard water, we recommend installing a water-softening device.

Un tableau montrant les différentes options avec un système split.

Water inlet temperatures and flow rate

The smooth operation of water-cooled condensing units depends on the quality of heat exchange between the refrigerant and the water, either rejecting calories (cooling mode) or drawing them from the water (heating mode).

Water inlet temperature and flow rate are essential parameters for the proper operation of the system. The water flow rate must be adapted to the water inlet temperature, which must be within the specified operating range (Tmin / Tmax).

For example, in cooling mode, if the water temperature is too high or the flow rate too low, the heat will not be dissipated and the unit will not operate (HP cut-out).

The tables below summarize the conditions that may cause the unit to malfunction or trip:

Cooling only" models

Reversible" models

Un tableau présentant différents types de thermomètres pour les systèmes de climatisation.

Cooling-only models are designed to operate correctly when supplied with mains water at a temperature of around +15°C and a pressure of around 4 bar, with a wide tolerance around these values.

On the other hand, for water loop applications (cooling-only or reversible models), it is essential to check with the loop manager to obtain guaranteed water temperatures and flow rates. Refer to the data tables for each range for the temperature and flow rate conditions to be met. Consult us to check the compatibility between the machine and the loop characteristics. 

Note: for reversible models, it is necessary to install a device for measuring and adjusting the water flow rate at the inlet to each machine (see flowmeter valve).

Good to know

We can adapt our machines to higher loop temperatures than those permitted for catalog versions. Please do not hesitate to contact us.
We also manufacture reversible tri-splits on request. Please consult us.