Emerson CopelandScroll ZX 401, User Manual

Page: 17 / 32

17
Expansion Valve Selection for Low Ambient Application
For systems expected to operate in varying ambient conditions – namely summer and winter temperatures – the expansion valve (TXV
or EXV) sizing should take into consideration the maximum expected saturated condensing temperature at high ambient conditions
(summer) and the minimum expected saturated condensing temperature, set at -25°C, during low ambient conditions (winter).
The chosen expansion valve’s operating capacities should be well within these limits to ensure satisfactory system performance.
In the event that different expansion valves come up for the two conditions, the valve for low ambient condition should be
selected. This means that at higher ambient, the valve will be oversized. However, if the valve at the high ambient is selected, it
may be too small during low ambient condition.
Location and Fixing
The unit should always be installed in a location that ensures clean air flow. It is recommended that a clearance of 300 mm from the wall
(or the next unit) be maintained from the unit’s left and rear panels whereas a clearance of 500 mm must be maintained from the unit’s
right, top and front panels (seen facing the front of the unit). Both service access and airflow have been considered in making these
recommendations. Where multiple units are to be installed in the same location, the contractor needs to consider each individual case
carefully. There can be many variations of unit quantities and available space and it is not the intention of this manual to go over these.
Ideally, the unit should be mounted on a solid concrete slab with anti-vibration pads between unit feet and concrete. However the ZX
condensing unit has also been designed for wall mounting on suitable brackets. Wall mounting brackets are not included. Another factor
to consider in finding a good installation site is the direction of the prevailing wind. For example if the air leaving the condenser faces
the prevailing wind, the air flow through the condenser can be impeded, causing high condensing temperatures ultimately resulting in
reducing unit life. A baffle is a remedy for this situation.
840
500
500
300
300 500 352
70 70
23
90
172
424
Power Supply Hole
Suction Service Valve
Liquid Service Valve
388
110
580
2 HOLESØ15MM DIA
2-R7.5MM GROOVE
1029
21
1242
172
90
500 300
300
500
352
70 70
1029
23
424
94
Liquid Service Valve
Suction Service Valve
Power Supply Hole
388
110
580
2 HOLESØ15MM DIA
2-R7.5MM GROOVE
500
21
Fixing dimensions and distances - Single fan unit
Fixing dimensions and distances - Dual fan unit