How To Operate Using The Service Switch The Outdoor Unit; How To Operate The Outdoor Unit Independently - Hitachi RAK-25NH4 Service Manual

HOW TO OPERATE USING THE SERVICE SWITCH THE OUTDOOR UNIT

MODEL RAC-25NH4, RAC-35NH4, RAC-50NH4
1. Turn off the power supply to outdoor unit and then turn on again.
2. Remove the electrical box cover.
LD303 (red) will light and the unit will operate in the forced cooling mode at this time.
Never operate the unit for
more than 5 minutes.
RAC-25NH4, RAC-35NH4
Electrical Box Cover
RAC-50NH4
(Cautions)
(1) If interface signal (DC 35V) terminals C and D are not connected when the outdoor unit is in forced cool mode, the outdoor
unit defect indicator (LD301) will blink 9 times during operation to indicate communication error.
(2) If checking is done with the compressor connector disconnected, the unit will continue normal operation when the
electrical parts are normal, or it will repeat operating for approx. one minute and stop due to overload power limit cut,
or it will operate in the overload status.
Be sure to push the service switch again to stop the forced cool operation.

HOW TO OPERATE THE OUTDOOR UNIT INDEPENDENTLY

1. Connect the large dia. pipe side and small dia. pipe side service valves using a pipe.
Connect the small diameter
service value and the large
diameter service valve using the
reducing union and copper pipe
as shown on the right.
Charge refrigerant of 300g
after vacuuming ( 1 )
The operation method is the same as "How to operate using the connector to servicing the outdoor unit".
1 The charging amount of 300g is equivalent to the load in normal operation.
Electrical Box Cover
Outdoor unit
Compressor
Reversing
valve
– 114 –
Service switch
(forced-cooling mode is set by
pressing for 1 second or more,
and stopped by pressing again.)
(1) Reducing union
Large dia. service valve
Reducing union
(2) Copper pipe (2/8" and 1/2")
(2/8" and 3/8")
(3) Shorting leads
Copper pipe
(2/8")
Do not operate for more than 5
Small diameter
minutes
service valve
Self diagnosis lamps
(LD303, 302, 301)
Parts to be prepared
2/8" (6.35mm)
1/2" (12.7mm)
2 leads approx. 10 cm long
with alligator clip or IC clip