Water Piping - Trane RTWB Helical-Rotary Installation Operation & Maintenance

Condenser piping
components
"Piping components" include all
devices and controls used to
provide proper water-system
operation and unit operating safety.
These components and their
general locations are given below.
Entering condenser-water piping.
• Air vents (to bleed air from
system)
• Water pressure gauges with
shutoff valves
• Vibration eliminators
• Shutoff (isolation) valves.
• Thermometers
• Cleanout tees
• Pipe strainer
Leaving condenser-water piping
• Air vents (to bleed air from
system)
• Water pressure gauges with
shutoff valves
• Pipe unions
• Vibration eliminators
• Shutoff (isolation) valve
• Thermometers
• Cleanout tees
• Balancing valve
• Pressure relief valve
To prevent condenser damage do
not exceed 10 bar water pressure.
To prevent tube damage, install a
strainer in the water inlet piping of
the condenser.
RTWB-SVN01B-E4
Installation Mechanical
Condenser Water
Limitation (RTWB only)
The RTWB starts and operate
satisfactorily over a wide range of
load conditions with controlled
entering condenser water
temperature. Reducing the
condenser water temperature is an
effective method of lowering the
power input to the compressors. The
optimum condenser water
temperature is related to the leaving
chilled water temperature and the
percentage of load on the chiller.
Nevertheless it is required to
maintain a minimum temperature
differential of 18°C between the
leaving chilled water temperature
and the leaving condenser
temperature. This minimum
temperature differential must be
reached within 2 minutes from start-
up and maintained thereafter.
Furthermore, the entering
condenser water temperature
should never drop below 20°C,
whatever the other operating
conditions of the chiller.
When one of these 2 parameters is
expected to drop below the limit
stated here above, even at start up,
it is required that some form of
condenser water temperature
control be implemented to satisfy
compressor safety and to ensure
optimum chiller performance.
There are numerous methods to
control condenser water
temperature. Methods other than
those shown can be employed to
achieve the same results. Contact
your local Trane office for details.
Throttling valve
This method maintains condensing
pressure and temperature by
throttling water flow leaving the
condenser in response to condenser
pressure or system differential
pressures.
Figure 8
1 = 2-way valve
2 = Customer controller
3 = Condenser water pump
4 = To/from cooling device
5 = Temperature sensor
Advantages:
• Good control with proper valve
sizing at relatively low cost.
• Pumping cost can be reduced.
Disadvantages:
• Increased rate of fouling due to
lower condenser water velocity.
• Requires pumps that can
accommodate variable flow.
13