McQuay M4AC 080 C, Manual

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Water buffer tank & pipe connection
The unit does not come with a water buffer tank. However, the unit does come with an 8 liters expansion
tank.
(A 135L water tank is available as optional item)
The external water piping connection can be made either from the left or right side of the unit. Connection is
done with
I
1-1/4” female thread couplings for both supply and return pipes.
Anti-freeze protection
The chiller unit has several anti-freeze protection features:
1.
Brazed plate heat exchanger anti-freeze
The BPHE has a strip heater around it to prevent water freezing inside.
2 . Auto mode
The chiller controller will force-on the unit to the heat mode if the outdoor ambient air temperature
becomes too cold.
Maintenance
In order to facilitate maintenance of the controller, a rocker switch is provided to power-off the supply to the
PCB. However, switching off this switch will not disconnect the main incoming power supply to the chiller
unit.
Coil Guard
The unit also comes with two sets of coil guards (i.e. on the left and right side coils). Each guard is basically
a metal mesh which protects the coil from damage due to a side impact on the coil surface itself.
Fin Coating
The finned tube heat exchanger coil used on the chiller unit is made of staggered rows of 3/8” seamless
copper tubes, mechanically expanded into die-formed louvered fins. The slit openings on the fins enhance
the heat transfer coefficient between the fin surfaces and air.
In order to protect these fins from corrosion, a special fin coating (gold fin) is applied on the surface. This
coating is standard on the heat pump version, whereas it is an option on the cooling only model.
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