Yazaki CH-K100, Operating Instruction

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water is cooled to 44.6°F
(7°C)
while the
refrigerant vapor is attracted to the
concentrated solution dripping over the
absorber tubing bundle.
Absorber
A deep vacuum in the absorber is
maintained by the affinity of the concentrated
solution from the LGE for the refrigerant
vapor formed in the evaporator. Refrigerant
vapor is absorbed by the concentrated
lithium bromide solution flowing across the
surface of the absorber tube bundle. The
heat of condensation and dilution are
removed by the cooling water and rejected to
a cooling tower. The resulting dilute solution
is preheated through heat exchangers before
the solution pump returns it to the HGE
where the cycle is repeated.
Figure 1
– DOUBLE-EFFECT
ABSORPTION CYCLE (COOLING)
HEATING OPERATION
High Temperature Generator
(HGE)
The solution boils in the HGE and
superheated refrigerant vapor and semi-
concentrated solution flow into the primary
separator in exactly the same manner as in
the cooling cycle.
Low Temperature Generator
(LGE)
In Heat mode, the changeover valve
opens a path for the semi-concentrated
solution to flow out of the primary separator
directly into the Absorber/Evaporator sump.
Therefore,
the LGE and both heat
exchangers are completely bypassed while
in Heat mode.
Condenser/Absorber
It is imperative that there be NO
COOLING WATER FLOW in the Heat mode.
As such, neither the Condenser nor the
Absorber have any function in Heat mode.
Evaporator
Since the Evaporator acts as the
Condenser in Heat mode, hot refrigerant
vapor condenses on the surface of the
evaporator coil and heat, equivalent to the
latent heat of the refrigerant, is transferred to
the hot water circuit, heating it to a leaving
temperature of 131°F
(55°C)
. The condensed
refrigerant drips off the evaporator and into
the absorber sump where it mixes with the
semi-concentrated solution, diluting it once
again.
Figure 2
– DOUBLE-EFFECT
ABSORPTION CYCLE (HEATING)