Fisher FHIF-WHS-120CE3, Service Manual

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R32 ATW Service Manual
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after completion.
3) The outdoor unit cannot be connected when holding pressure.
11.3.7 Vacuum pumping
1) A vacuum pump with a vacuum degree of -0.1μm or less and gas displacement of above 40L/min
shall be used.
2) The outdoor unit does not need to be vacuumed. Do not open the shut-off valve on the gas side or
liquid side of the outdoor unit.
3) Confirm that the vacuum pump can work below -0.1MPa after running for more than 1 hour. If it
cannot work below -0.1MPa after running for more than 2 hours, it indicates that there is moisture or
gas leakage inside and needs to be checked.
4) The vacuum pump must be equipped with a check valve.
11.3.8 Adding amount of refrigerant
The calculation method of the adding amount of refrigerant is shown in the following table, based on
the pipe diameter and length of connection liquid side piping between outdoor unit and the hydronic
module.
Liquid pipe diameter (mm) Pipe length (m) Adding amount of refrigerant (kg)
φ9.52 ≤
5
φ9.52 >5 Add 0.03kg for each additional 1m
Note: R32 refrigerant must be charged in liquid form with fixed amount measured by electronic scale.
11.3.9 Instructions for use of the shut-off valve
1) It shall be in OFF state when delivery.
2) Open or close the valve with a 6 mm hex wrench, counterclockwise turning for opening and
clockwise turning for closing.
3) The valve cover must be tightened after the operation.
4) The operation of vacuuming and refrigerant injection at the service port must be operated with the
special tool R32. Inject the refrigerant at the gas side valve service port, and vacuum at the liquid side
and the gas side valve service port.
Attention
 Do not mix tools and measuring instruments used for different refrigerants and in direct contact
with the refrigerant.
 Never remove air with refrigerant gas.
 When the vacuum degree cannot reach -0.1MPa, please consider whether there is a possibility of
leakage. Please
confirm again if there is any leakage. If there is no leak, run the vacuum
pump for one or two more hours.