Yazaki CH-K100, Operating Instruction

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GENERAL
These instructions are intended to
acquaint the Owner/End User with the
operation
and general maintenance
requirements of Yazaki CH-K gas-fired
double-effect Absorption Chiller-Heaters.
Please read ALL instructions carefully and
observe precautions. Failure to operate and
maintain this equipment in accordance with
the OPERATING INSTRUCTIONS may
affect the equipment performance and
product Warranty.
If the equipment does not operate as
expected, check the Troubleshooting Guide
in these instructions BEFORE calling your
Yazaki Authorized Service Provider
(ASP)
.
This approach will not only save cost but
also avoid any unnecessary downtime.
ABSORPTION PRINCIPLE
Yazaki absorption chiller-heaters use a
solution of lithium bromide and water, under
a vacuum, as the working fluid. Water is the
refrigerant and lithium bromide is the
absorbent.
During cooling operation, refrigerant
liquid boils under the influence of a deep
vacuum in the evaporator and creates a
refrigeration effect which removes heat from
the chilled water circuit.
The double-effect absorption cycle has
two generators, one heated by a burner and
the other heated by superheated refrigerant
vapor. It also utilizes a condenser, an
evaporator, and an absorber.
The absorber and condenser are water
cooled and heat is normally rejected to a
cooling tower, though ground loop is also an
option.
COOLING OPERATION
High Temperature Generator
(HGE)
T
he gas burner heats a dilute lithium
bromide solution in the HE and the boiling
process drives superheated refrigerant vapor
and droplets of semi-concentrated solution
into the primary separator. The semi-
concentrated solution is precooled through a
heat exchanger before flowing into the LGE.
Low Temperature Generator
(LGE)
Superheated refrigerant vapor from the
primary separator heats the semi-
concentrated solution in the LGE.
Refrigerant vapor that is liberated from this
solution flows into the Condenser while the
fully concentrated lithium bromide solution is
precooled through another heat exchanger
before flowing to the Absorber.
Condenser
In the condenser, refrigerant vapor is
condensed on the surface of the condenser
tubing bundle and latent heat, removed by
the cooling water, is rejected to a cooling
tower. Refrigerant liquid accumulates in the
condenser and then passes through an
orifice into the evaporator.
Evaporator
In the evaporator, refrigerant liquid is
exposed to a substantially deeper vacuum
than in the condenser due to the influence of
the absorber. As refrigerant liquid flows over
the surface of the evaporator tubing bundle,
it boils and removes from the chilled water
circuit an amount of heat equivalent to the
latent heat of the refrigerant. When at
design condition, the recirculating chilled