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You’ve got questions, we’ve got answers.

If you have a precise question, or if you would like to get more details on a particular topic, contact us.

How to clean up a reversible installation?

The reversible installation and particularly the heat-pumps are often subject of pollution,principally due to moisture in the circuit.
Presence of moisture in a refrigerating installation generate the decomposition of the refrigerant and oil.
It causes the formation of organic acids which can create:
– The circuit corrosion
– The deterioration of the motor’s windings
– The formation of sludge
– The compressor’s destruction

In the case of compressor’s carbonization, and after its replacement, it is not sufficient to change the polluted refrigerant.
Indeed, in such a case, it remains inevitably in the refrigerating circuit some acid oil and some residues which have not been evacuated.

To resolve such problems, CARLY recommends two types of actions:
– a preventive method is to install a bi-flow filter drier, DDCY, and a sight glass, VCYL which allows to control the DDCY efficiency on the liquid line before the startup of the installation.
– a curative method is to install a cleaning bi-flow filter drier, DDNCY, on the liquid line when the presence of acidity is detected or when a compressor broke down.

Setting up a cleaning bi-flow filter drier DDNCY enable to treat both fluid and oil, while maintaining the refrigerant in the installation.
This cleaning operation can thus be realized without creating a prolonged stopping of the heat pump.
It can be initiated in any season since the cleaning filter DDNCY is designed to function in 2 direction of the circulation.
It is no longer necessary to restrain the operation of the heat pump in a hot or cold mode to carry out the cleaning of both refrigerant and oil.

The control of effectiveness of the depollution is done by sampling and analysis of the oil, using TESTOIL-MAS or TESTOIL-POE in order to check its acidity.
To increase the rapidity of the refrigerant cleanup, CARLY recommends the installation of a suction filter drier FNCY (burn-out, single flow), between de 4-ways valve and the suction of the compressor.
With the CARLY DDNCY filter, the refrigerant will be filtered and cleaned up before being directed to the expansion valves and the evaporators, and thanks to the CARLY FNCY filter, it will be filtered and cleaned up before getting into the compressor.

The DDNCY and FNCY are for temporary use only.
In order to avoid a pressure drop which can decrease the efficiency of the installation, it is absolutely necessary to replace them after the cleaning operation.
The DDNCY will be replaced by a bi-flow filter drier DDCY equivalent in size (for example a DDNCY 164 will be replaced by a DDCY 164), and the FNCY will be replaced by a cleaning filter FACY equivalent in size. (for example a FNCY 285 will be replaced by a FACY 285)

Is it possible to install a vibration eliminator at 90° ?

This is possible with a combination of 2 eliminators EVCYAC at 90°.

Regular installation:

CARLY solution:

CARLY also offers a very flexible vibration eliminator, “double effect” EVCYDEAC, which replaces the installation of 2 eliminators.

For more informations, click on the following link to consult the technical data sheet : EVCYDEAC – eliminator double effect.

How to choose the size of a liquid receiver?

The dimension of the liquid receiver has to take into account the respective volume(s) of
– the condenser(s) – Vcond
– the evaporator(s) – Vevap
– and the liquid line between the receiver and the expansion valve(s) – VLL.

An easy formula enables to calculate the dimension of the receiver:
V= Vcond x 0.2 + Vevap x 0.8 + VLL

In order to avoid an excessive increase in pressure in the receiver, due to the liquid dilatation, it is essential to provide for an additional safety volume (25% to 30% of total refrigerant volume).

Then, the volume of the receiver to select will be at least:
Vres = V1 x 1.25.

What is the difference between CARLYCLEAN and CARLYNET?

To remove grease from an area, there are two methods: water grease removal (product made of water and active agents) and solvent grease removal.

Water grease removal is made of surface-active and anti-oxidizing agents in solution in water. Dirty marks are removed by emulsion: greasy bodies (non miscible in water) are broken up into thin particles in the cleaning liquid (water) thanks to surface-active.
If the cleaning product is concentrated, rinsing is essential to remove all marks of the product.
CARLYCLEAN is a concentrated alkaline (non acid) water grease remover, to be used pure or diluted according to the level of dirt of the fin exchanger (evaporator or condenser). The product is efficient against oils, sludge…

Solvent grease removal is the principle of making greasy bodies soluble without adulterating them. Fast evaporation of the solvent enables immediate drying of the area. Solvent drying is indicated for very greasy areas, such as fitted groups or units installed in the kitchens (restaurants, bars).
CARLYNET is a solvent grease remover formulated without chlorides or fluorides.

Which oil level regulator should I install on my compressor ?

Oil level regulators are usually installed instead of the oil level sight glasses, and positioned on the compressor crankcases.
Oil level sight glasses are not all the same and they depend on the compressor brand and reference.
Oil level sight glasses can be different among the same range of compressors of the same brand.
Because of the dimensions of their cylinder heads, some compressors do not permit the direct fitting of the oil level regulators. In these cases, it is then necessary to install adapters between the oil level regulators and the compressor crankcases.

CARLY offers some help in the selection of oil level regulators in a document where you will find different possible montages of level regulators and adapters, according to compressor brands and references.

The solution recommended by CARLY is indicated in bold and all other possibilities are also indicated.

To select a regulator to associate to a model of compressor, click here.

For help in the selection of all oil line components, do not hesitate to use CARLYSOFT.

Is it possible to make a return by gravity on CARLY suction accumulators ?

A return by gravity can be made on CARLY LCY/LCYE suction accumulators, from 15 litre model, thanks to a connexion located on the lower part of the accumulator.

This connexion enables the oil return in the suction collector.

What do S and MMS mean on CARLY products ?

Refrigerating pipes used are generally in inch (1/4, 3/8…) but certain countries (Germany, Italy…) use metric pipes (6mm, 8 mm, 10mm…).
The CARLY products which part number ends with S are products to be welded for inch pipes.
The CARLY products which part number ends with MMS are products to be welded for metric pipes.
When pipes in inch and metric have very close diameters and that the sets of brazing are respected, the part numbers end with S/MMS.

The CARLY products, which part number ends neither with S nor MMS, are products with flare connections to screw (SAE).

Where a muffler should be installed ?

The muffler is used to reduce the noise related to the gas pulsations.
The CARLY muffler SCY must be mounted on the discharge line, after the compressor at a quite precise distance which depends on the following parameters :

  • Compressor: Rotation speed
  • Number of cylinders
  • Type of refrigerant
  • Discharge line diameter
  • Operating conditions of the installation

The muffler efficiency depends on its implantation and its fitting on the pipe. It must be joined to a vibration eliminator and be correctly clamped.
For more information, consult the SCY data sheet, and contact our technical department to determine the optimum distance of implantation.

Are CARLY cleaning and disinfecting products usable in the food industry ?

Yes. All active elements part of the composition of CARLYCLEAN (heat exchangers detergent), CARLYBIO (heat exchangers disinfectant) and CARLYPRO (heat exchangers detergent and disinfectant) are authorized by the French decree from 08/09/1999, which regulate the cleaning products for containers designed to be in contact with food. A rinsing with water after the cleaning and disinfection is obligatory