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If above solutions don’t work, please contact your installer or Davey service agent with detailed information
and your model number. Don’t try to repair it yourself.
NOTE:
If the following conditions happen, please stop the machine immediately, and cut off the power
supply
immediately, then contact your dealer or Davey:
1. Inaccurate switch action.
2. The fuse is frequently broken or leakage circuit breaker jumped.
Guidance for flammable gas maintenance.
Please refer to the technical service manual for more information on
service and maintenance.
Any maintenance on the refrigeration circuit including handling, installation,
cleaning and servicing and disposal must be carried out by licensed personnel and in
compliance with national gas regulations
1. Detection of flammable refrigerants
Under no circumstances should potential sources of ignition be used in the searching for or detection of
refrigerant leaks. A halide torch (or any other detector using a naked flame) should not be used.
2. Leak detection method
Electronic leak detectors may be used to detect refrigerant leaks but, in the case of flammable
refrigerants, the sensitivity may not be adequate, or may need re-calibration.
Any calibration of detection equipment should be done in a refrigerant free area.
Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant used.
Leak detection equipment should be set at a percentage of the LFL of the refrigerant and should be
calibrated to the refrigerant used, and the appropriate percentage of gas (25% maximum) is confirmed.
Leak detection fluids are suitable for use with most refrigerants but the use r of detergents containing
chlorine shall be avoided as the chlorine may react with the refrigerant and corrode the copper pipework.
If a leak is suspected, all naked flames should be removed or extinguished.
If a leakage of refrigerant is found which requires brazing, all of the refrigerant shall be recovered from
the system, or isolated (by means of shut off valves) in a part of the system remote from the leak. For
appliances containing flammable refrigerants, oxygen free nitrogen (OFN) should be purged through the
system both before and during the brazing process.
3. Refrigerant removal and evacuation
When breaking into the refrigerant circuit to make repairs, or for any other purpose, conventional
procedures should be followed. For flammable refrigerants, it is important that best practice is followed
since flammability is a consideration.
The following procedure should be adhered to;
Remove refrigerant
Purge the circuit with inert gas
Evacuate
Purge again with inert gas
Open the circuit by cutting or brazing
The refrigerant charge should be recovered into the correct recovery cyclinders. For flammable
refrigerants, the system should be flushed with Oxygen Free Nitrogen (OFN) to render the unit safe. This
process may need to be repeated several times. Compressed air or oxygen cannot be used for purging
refrigerant systems.
For appliance containing flammable refrigerants, flushing should be achieved by breaking the vacuum in the
system with OFN and continuing to fill until the working pressure is achieved, then venting to atmosphere,
and finally fulling down to a vacuum. This process should be repeated until no refrigerant is within the
system. When the final OFN charge is used, the system should be vented down to atmospheric pressure to
enable work to take place. This operation is vital if brazing operations on pipework are to take place.
Ensure that the outlet for the vacuum pump is not close to any ignition sources and that ventilation is available.
