Operation Manual
23
ENGLISH
A. Connect the main line of the gauge to the R-407 bottle stopcock.
B. Open the bottle stopcock and purge the section of tubing.
C. Open the high-pressure valve.
D. Pressurise the equipment to equal the pressure of the bottle.
E. Close all gauge valves.
F. Start the machine. The low-pressure switch may be activated. To continue with the charge, you must disconnect
the low-pressure switch in the electrical panel (just while the charging operation is underway).
G. Open the low-pressure valve until the pressure is above the trip point of the low-pressure switch.
H. Once in a while, close the LO valve of the gauges in order to confirm the real pressure of intake.
I. Verify that the outflow pressure is not above the normal range for normal working conditions.
J. When the correct weight of refrigerant has been charged, close the LO valve.
K. When the equipment is functioning according to the specified working conditions, close the valve of the charging
bottle and disconnect the tubes taking precautions regarding gas purge.
L. Place the caps on the supply and return lines of the compressor.
Detecting Leaks:
Symptoms of a leak
Leaks will cause a decrease in the refrigerant charge in the equipment. Low refrigerant charge may be the cause of:
1. The temperature of the evaporating unit is too low. This may be caused by an obstructed fluid line or the
incorrect operation of a capillary. The consequences may be very serious, for example ice may form on
evaporating unit, etc.
2. The compressor is functioning on cycles which are too short. This may also be due to incorrect functioning of
control humidistat.
3. Compressor is overheated: low gas charge makes for insufficient flow of vapours to cool the compressor. This
may cause the tripping of the internal thermal indicator of the compressor.
4. The compressor operates continuously, there is not enough refrigerant to obtain the desired results, and since
the specified temperatures are not reached, the equipment does not shut down.
In any case, it is better not to wait until a leak appears, and for this reason, it is recommended that the equipment be
serviced regularly.
Methods for Searching for a Gas Leak:
There are various tools on the market used in order to detect leaks, although not all of them are sufficiently sensitive to
certain types of refrigerants. It is very important to choose an adequate detector for the refrigerant used for this
equipment and that the maintenance guidelines by followed.
You can also use soap bubbles (liquid detergent in a spray bottle) to detect leaks.
Other methods such as halogen lighters and additives may also be used to detect leaks.
The R-407-C Gas:
The R 407 C liquid, unlike the R22, is not a pure liquid, but a compound mixed to 23% of R32 + 25% of R125 +
52% of R134 A.
The R-407-C is NOT AN INFLAMMALBE gas; it has no flash point, and so is not subjected to the rules and
regulations of the transportation of inflammable gases
The R-407-C does not irritate the skin, eyes or mucous membranes and does not produce and side-effects.
It has a very low level of toxicity for one or many repeated exposures; it does not cause cancer or mutations.
The R-407-C is susceptible may cause freezing if it comes into contact with the skin, due to its immediate
evaporation.
As with all hydrocarbons, whether they are halogenated or not, the R-407-C gas may, although it has a very low
level of toxicity, cause anaesthetic or preanaesthetic conditions if inhaled deeply and within a closed area.
The compressors approved to work with this liquid are specific and are preloaded with polyol ester oil.
This oil, unlike mineral oil, is very hygroscopic and it very quickly absorbs the ambient air humidity, something
that can strongly after its lubricating abilities and lead in due time to the destruction of the compressor.