12/18/2015

Water Chillers and Maintenance part 1 Installation Checklist for Absorption Chillers

Water Chillers
and Maintenance
part 1
Installation Checklist for Absorption Chillers

Installation Checklist for Absorption Chillers



CHILLER COMMISSIONING:

Every chilled water system can be operated on the basis of meeting two goals:
Goal 1: Satisfy imposed cooling loads

• Maintain proper chilled water supply temperature to offset imposed sensible
and latent cooling loads.

• Maintain proper supply water flow in variable flow systems to minimize
pumping energy consumption.
Goal 2: Minimize the cost of cooling

• Maintain chilled water temperature as high as possible, but still low
enough to satisfy both sensible and latent cooling loads.

• Maintain condenser water supply temperature as low as feasible. Most
chillers operate satisfactorily with entering condenser water temperature
as low as 70°F. And, at least one chiller manufacturer rates its machines
for operation with an entering condenser water temperature of 55°F.

• Operate each chiller, to the maximum possible extent, in the 40–80%
load range.
To ensure that this type of operation is attainable, the chilled water system
must be properly installed and placed into service and its operation verified by
test, a process called commissioning.
The first step in this process is to verify that the chiller installation is correct
and in accordance with both the design and the manufacturer’s recommendations.
The design engineer should be retained to review the installation process and
perform a final inspection to ensure compliance with the design requirements.
Before the chiller can be started for the first time, the chilled water pump(s)
must be placed in operation and the chilled water flow “balanced” to within ±5%
of design rates. The basic steps required to place the chilled water pump in service
include the following:

1. Check pump installation, including mountings, vibration isolators, and
connectors,
and piping specialties (valves, strainer, pressure gauges,
thermometers, etc.).
2. Check pump shaft and coupling alignment.
3. Lubricate pump shaft bearings as required by the manufacturer.
4. Lubricate motor shaft bearings as required by the manufacturer.
5. Turn shaft by hand to make sure the pump and motor turn freely.
6. “Bump” the motor on and check for proper rotation direction.

The air-cooled condenser or condenser water system must be placed into operation
(see the section “Tower Commissioning” in Chapter 15). System controls
must be tested and their proper operation must be confirmed. Chillers should be
initially placed into service only by the manufacturer’s service technicians, a process
often called factory start-up.
The following checklist may be used for verifying both chiller installation and
functional performance upon start-up:

General Installation Checklist

1. Test and balance completed (chilled water (CHW) and condenser water
(CDW) flows with –5% to +10% of design).
2. Observe no visible water or oil leaks.
3. Observe no unusual noise or vibration.
4. Chilled water piping insulation in good condition.
5. Pressure gauges, thermometers installed and operable.
6. Confirm that O & M manuals are onsite.
7. Confirm that training was provided for operating staff.

Additional Installation Checklist for Absorption Chillers

1. Confirm that the steam control valve is installed and operating for an
indirect-fired chiller.
2. Confirm that the chiller has been leak tested according to manufacturer’s
instruction.
3. Confirm that unit was evacuated properly before charging with refrigerant
and solution.
4. Confirm that distilled water was used for refrigerant charge and proper
amount of inhibitor added.
5. Confirm that the proper amount of lithium bromide was installed.
6. Confirm that the proper amount of octyl alcohol was installed.
7. Test electrical service to each pump for
8. Test operating amps for each pump.


Functional Performance Checklist

1. Confirm that the factory start-up and tests were completed and the chiller
is ready to be placed into service.
2. Determine entering CHW temperature and compare to design.
3. Determine leaving CHW temperature is within 1°F of setpoint.
4. Compute CHW range and compare to design.

kandi younes

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