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NOTE: Once the 42GM unit has been installed, ensure
that it is level or slightly sloped towards the rear of the
unit (to ensure that the condensate is drained correctly).
•
Connect the flexible water pipes. Each flexible pipe is
equipped with a 1/” gas screw connector.
•
Connect the condensate drain pipe, using clear 10 mm
bore pipe and provide a fall of 10 mm/metre over the
whole horizontal pipe run. Install a 50 mm (minimum)
siphon to prevent gases and odours from flowing back
into the ceiling void (see Fig. 4).
NOTE: The condensate drain pipe has to be attached to
the drain pan by a collar (not supplied by Carrier).
When all modules are installed in this way open the shut-
off valves on the manifolds, bleed all air from the circuits.
Bleed valves are on the system manifolds (no purge on the
unit) then pressurise the system.
Now the electrical connections can be made. Do not switch
the power on until the connection and earthing are complete.
4.3 - removing a 42GM unit
Disconnect the power supply before carrying out any work
on a 4GM unit by switching off the power supply at the
isolator provided for the purpose during installation (iso-
lator not supplied by Carrier):
•
Disconnect the power supply cable and the earth wire
fitted with a flat tag.
Disconnect the power supply cable of the user inter-
face.
Disconnect the power supply cable for the BMS bus.
Disconnect the connection cable for the window contact.
Disconnect the connection cable for the motorised
fresh air valve.
•
Disconnect the condensate drain pipe.
•
Close the water valves on the system supply manifolds.
•
Disconnect the flexible water pipes by unscrewing the
1/” gas connectors.
WARNING: Since the flexible water pipes do not have
drain valves, provide:
•
either a receiver to allow the flexible pipes and part
of the cooling coil to be drained (in this case do not
drain the flexible riser pipes during the removal of
the unit);
•
or male plugs to be screwed onto the flexible pipes.
•
Move the hydraulic lift and the support block under
the 4GM unit.
•
Loosen the clamping nut on the rear suspension rail.
•
Raise the hydraulic lift slightly (approx. 10 mm) to
disengage the two hooks at the front of the 4GM from
their rectangular seat in the front fastening support.
•
Lower the hydraulic lift and set the unit down.
...
6 mm hole at the top
Non-return valve
Slope 2%
Siphon
50 mm
Slope 2%
Clear Ø 10 mm ID pipe
(not supplied by Carrier)
Condensate
drain pipe
Ø 16 mm hole in the horizontal
pipe on the drain section
Joint
Non-return valve
Fig. 4