Installation, Operation, and Maintenance Manual
CA Series Heat Pumps -8733851021 (2025/04) US
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18.3.6 Checks to the Refrigerating Equipment
Where electrical components are being changed, they must be fit for the purpose
and to the correct specification. At all times the manufacturer's maintenance and
service guidelines must be followed. If in doubt, consult Bosch service and support
for assistance.
The following checks must be applied to installations using flammable refrigerants:
1. Ensure the actual refrigerant charge is in accordance with the room size
within which the refrigerant containing parts are installed.
2. Ensure that the ventilation machinery and outlets are operating adequately
and are not obstructed.
3. Check the secondary circuit for the presence of refrigerant, if an indirect
refrigerating circuit is being used.
4. Ensure the markings on the equipment continues to be visible and legible.
Markings and signs that are illegible must be corrected.
5. Ensure the refrigerating pipes or components are installed in a position
where they are unlikely to be exposed to any substance that may corrode
refrigerant containing components, unless the components are constructed
of materials that are inherently resistant to being corroded or are suitably
protected against being so corroded.
18.4 Checks to Electrical Devices
Repair and maintenance to electrical components must include initial safety checks
and component inspection procedures. If a fault exists that could compromise
safety, then electrical supply must NOT be connected to the circuit until the safety
fault is satisfactorily corrected. If the fault cannot be corrected immediately but it
is necessary to continue operation, an adequate temporary solution must be used.
This must be reported to the owner of the equipment, so all parties are advised.
The following are required initial safety checks:
1. Ensure that capacitors are discharged—this must be done in a safe manner
to avoid possibility of sparking.
2. Ensure that no live-electrical components and wiring are exposed while
charging, recovering, or purging the system.
3. Ensure that there is continuity of earth bonding.
18.5 Repairs to Sealed Components
Sealed-electrical components must be replaced.
18.6 Repair to Intrinsically Safe Components
Intrinsically safe components must be replaced.
18.7 Check Cabling
Check that cabling will not be subject to wear, corrosion, excessive pressure,
vibration, sharp edges, or any other adverse environmental effects. The check must
also take into account the effects of aging or continual vibrations from sources such
as compressors or fans.
18.8 Detection of Flammable Refrigerants
Under NO circumstances may 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) must NOT be used.
The following leak-detection methods are deemed acceptable for all refrigerant
systems:
• 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. (Detection equipment must be calibrated 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
must be set to a percentage for the Lower-Flammable Limit (LFL) (25%
maximum) of the gas that is confirmed.
• Leak detection fluids are also suitable for use with most refrigerants
but the use of detergents containing chlorine must be avoided as the
chlorine may react with the refrigerant and corrode the copper pipe-work.
Examples of leak detection fluids are:
◦
bubble method
◦
fluorescent method agents
If a leak is suspected, all naked flames must be removed/extinguished.
If a leakage of refrigerant is found that requires brazing, all of the refrigerant must
be recovered from the system or isolated (by means of shut-off valves) in a part of
the system remote from the leak.
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