Installation Guide
Page 27
mrcool.com
Outdoor Unit Installation
Refrigerant Piping Connection 
6
NOTE 
To distinguish the connectors to be connected to the indoor unit and outdoor unit, the 
connectors of the refrigerant pipe have been labelled “A”,“B”,“C”and “D”. Ensure the marks on 
the connector are the same to the indoor’s and outdoor’s respectively during connection.
Connecting the refrigerant pipe to outdoor unit
CAUTION
For your safety, always wear goggles and work gloves when connecting the pipes.
6 
Refrigerant Piping Connection
1. First remove the 
water tray on the 
outdoor unit as 
shown.
2. Do not remove the plastic seals from the 
outdoor unit and the appropriate 
refrigerant pipes until immediately before 
you connect them.
NOTE: The refrigerant pipes must be connected to the 
valves on the outdoor unit with as little stress as 
possible. 
IMPORTANT: Before you continue, it is essential that 
you read the following instructions carefully.
3. Align the refrigerant pipes correctly so that they line 
up with the valves and are not stressed. Place the 
screw connector on the refrigerant line just on to the 
thread on the outdoor unit and tighten the first few 
threads by hand.
4. Now tighten the bottom screw connector first and 
then the top screw connector using the open ended 
wrench (i.e. crescent or adjustable). Using the wrench, 
hold the points marked “1” and turn the nuts only at 
the points marked “2” (Select the appropriate wrench 
according to the dimensions of the connector).
Ensure that the screw connectors do not skew as you 
tighten them and work quickly. See below for the 
proper torque requirements.
After completing steps 1- 4, check that all the 
connections are sealed correctly using leak detection 
spray or soap suds. If any bubbles form, the system 
has a leak and the screw connectors must be 
retightened using an crescent or adjustable wrench.
IMPORTANT
Since the coupling works with tapping 
rings, it may leak if you undo and 
reconnect the pipes. This will also 
void the warranty.
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