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GB - 10
42HQM
Connection to the unit
Insufficient tightening torque will cause gas leaks.
Overtightening the fittings will damage the tube flaring and
cause gas leaks.
Tubing diameter
Torque
mm
(inches)
Nm
6.35
(1/4")
18
9.52
(3/8")
42
Once all connections have been completed, check for leaks by
applying soapy water to them.
Finally wrap connections with anti-condensate insulation and
tighten with tape, without exerting great pressure on the
insulation. Repair and cover any possible cracks in the
insulation.
Connection pipes and electric cables between indoor and
outdoor units must be fixed to the wall with appropriate
conduits.
Check
Pour water into the condensate drain pan and check that it flows
freely to the drain.
Refer to the outdoor unit installation manual for tube sizing,
and limitations (slope, length, number of bends allowed,
refrigerant charge, etc.).
For refrigerant tubes use seamless, insulated refrigeration grade
tube, (Cu DHP type according to ISO 1337), degreased and
deoxidized, suitable for operating pressures of at least 4200 kPa
and with a burst pressure of 20700 kPa.
Under no circumstances must sanitary type copper pipe be used.
Flaring the end of the tubing
Remove protective caps from the copper tube ends.
Position tube end downward, cut the tube to the required length
and remove the burrs with a reamer.
Remove flare nuts from the unit connections and place them on the
tube end.
Flare the tube with the flaring tool.
Flare end must not have any burrs or imperfections.
The length of the flared walls must be uniform.
Lubricate the tube end and thread of the flare fitting with anti-
freeze oil.
Finger-tighten the fitting several turns, then tighten it fully with
two wrenches by applying the tightening torque indicated in the
table.
Refrigerant connections
Adjustable wrench or torque wrench
Outdoor end
Indoor end
Tubing diameter
Gas
Liquid
Mod.
(Suction)
(Discharge)
mm
(inches)
mm
(inches)
42HQM 009-012
9.52
(3/8")
6.35
(1/4")
Tube
Tube insulation
Fastening tape