8
9
9.2
[Fig. 9.2.3]
<A> When the piping (from the twinning pipe) exceeds 2m [6ft], include a trap (gas pipe only) within 2m [6ft]. Make sure the height of the trap is 200mm [7-7/8 in] or more.
If there is no trap, oil can accumulate inside the pipe, causing a shortage of oil damaging the compressor.
(for PQHY-P·TSLMU-A/YSLMU-A)
2m[6ft]
D
A
D
A
B
C
<B> Example of piping connection (for PQHY-P·TSLMU-A/YSLMU-A)
A
: Indoor unit
B
: Trap (gas pipe only)
C
: Within 2 m [6ft]
D
: Twinning pipe
E
: Field-supplied piping
F
: Twinning kit
G
: Straight pipe length that is 500mm [19-11/16 in] or more
G
F
E
E
[Fig. 9.2.4]
<A> Install the piping so that oil will not accumulate in the stopped heat source unit. (both the liquid and the gas side for PQHY-P·TSLMU-A/YSLMU-A,
the high-pressure side only for PQRY-P·TSLMU-A/YSLMU-A)
1.
A
C
D
D
unit 1
unit 2
unit 3
C
D
D
B
unit 1
unit 2
unit 3
The NG example shows that oil accumulates because the units are installed on a reverse gradient while unit 1 is in operation, and unit 3 is stopped.
2.
unit 1
unit 2
unit 3
unit 1
unit 2
unit 3
h1
h1 = 0.2 m (7-7/8 in) max
unit 1
unit 2
unit 3
h1
h1 > 0.2 m (7-7/8 in)
The NG example shows that oil accumulates into units 1 and 2 while unit 3 is in operation, and units 1 and 2 are stopped. Vertical pipe height (h) should be 0.2 m (7-7/8 in) or below.
