Technical data

4.4 Water Connections
The water inlet and outlet connections
must be connected correctly as shown on
the labels fitted next to the fittings.
Connect the external water supply lines to the
water inlet and outlet fittings on the unit, refer to
section 9 for diameters and locations.
YCWM 60-150 Heat Pump
The YCWM unit can operate as a water to water
heat pump by reversing the cycle on the water
circuits using three way valves. Pressostatic two
way valves are available as an option for remote
location in the condenser water pipework.
This type of operation is possible only if
the condensers are supplied with well
water or disposable water. The system
cannot be used if a cooling tower is used.
The unit is supplied as standard in the cooling
mode only. If necessary the change to heating
mode is carried out by York Personnel during
commissioning and first time strart-up of the unit,
when requested.
4.5 Refrigerant Connections
For cooling of YCRM units, condensers are usually
of the remote air-cooled type either roof or ground
level mounted. Refrigerant systems should be
designed and installed by suitably qualified
persons in compliance with relevant national codes
and standards. The complete pipework system
and condenser must have a Design Working
Pressure of at least 30 barg.
When the unit has been located in its final position,
the refrigerant system pipework can be
connected. Pipework and fittings MUST be
separately supported and not cause any loading on
the unit. Flexible connections are recommended
and will also minimise transmission of vibrations to
the building.
Pipework Design
The following notes give guidance but should not
be considered exhaustive.
P-traps and double risers may be required when
the condenser is sighted above the unit. Horizontal
runs of the liquid line should be inclined slightly
towards the YCRM unit.
An in-line receiver should not be installed in the
refrigerant system.
Where the condenser is above or level with the
unit, the discharge line should rise to at least the
top edge of the condenser at some point. This will
prevent liquid draining back to the compressor
during the off cycle.
Elbows, bends and valves should be minimised to
reduce pressure drop and prevent loss of
performance. The liquid line in particular should be
designed for minimum pressure drop to avoid
flashing in the liquid line which will cause loss of
performance and fault conditions to
occur. Particular care should be taken where the
condenser is below or level with the unit.
035B40022-000 4-3