Filter
Top Products
ABS-PRC001-EN36
Hot Water Piping
The hot water system must be designed
such that it will avoid fluctuations in the
pressure differences across the control
valve. Trane absorption chillers for use
with hot water may be used at an
entering hot-water temperature of 270°F
[132°C] or below. Piping for a typical hot
water installation using a temperature of
270°F [132°C] or less is shown in Figure
JC-2. In this arrangement, a three-way
energy valve is used to control capacity
by varying the quantity of hot water
flowing through the chiller, while
maintaining a constant supply and
return flow rate. As shown in Figure
JC-3, a two-way energy valve can also
be used where the return and supply
flow rates can vary. The generator
design is rated to 150 psig [10.3 bars]
with a 400 psig [27.6 bars] optional
design available.
When the supply-water temperature
exceeds 270°F [132°C], a separate
circulating pump is recommended in a
run-around loop as shown in Figure
JC-4. The hot water for the absorption
machine should be taken from a header
installed between the hot-water supply
and return mains. The flow of hot water
through the machine is held constant,
but the temperature of the circulating
water is varied to meet load
requirements by modulating the amount
of high-temperature supply water added
to the loop. This is done by installing a
two-way modulating valve at the loop
outlet. The valve responds to the chilled-
water temperatures, but limits the water
temperature entering the machine to a
maximum of 270°F [132°C].
Hot Water Valves
Trane provides hot-water temperature-
control valves with the machine for
installation by the contractor at the job
site. These valves are selected by The
Trane company based on data provided
by the contractor (*i.e. water flow to be
used and the design pressure-drop
across the valve.)
It is desirable to use the smallest valve,
with the highest pressure drop,
appropriate to the design water flow and
allowable pressure drop in the system.
The smaller the valve, the better the
control.
Figure JC-2. Hot water supply piping – 270°F and below with 3-way energy valve
Job Site
Connections
Hot Water
Piping
Figure JC-3. Hot water supply piping – 270°F and below with 2-way energy valve