and Start Up
Just as important as selecting the right
equipment for your application, providing the correct
installation will ensure your cooling equipment does the job
and will operate maintenance free.
Installations can be broken out into several
Mechanical Room and Plant Layout
Good planning will ensure your installation
will go as planned and will keep costs down and on budget.
It will also reduce issues relating to maintenance access
and future growth.
You will need the equipment dimensions,
shipping and operating weight, moving and support
requirements, maintenance access points, electrical
requirements (MCA, Voltage, Connection Points and necessary
disconnects), city water and sanitary sewer requirements,
and pipe connection sizes and locations.
Setting the cooling equipment in the desired
Depending n the size of the equipment and the
location of where it is to be placed, you may need properly
sized lifts, cranes and other equipment to move it into
You should plan your route to ensure there
are no obstructions or obstacles in moving your cooling
equipment. Also ensure what are the limiting factors in the
size of the cooling equipment, like doorways, loading docks,
ceiling heights and the method of shipping to your facility
(width and height).
Locate the facility services and ensure they are adequate
for the cooling equipment needs.
Find out what your power needs are and locate
them in the plant relative to the cooling equipment
location. Also locate both city water line size and location
and make sure it is also adequate. Any draining, bleed-off
of process cooling water must go into a sanitary sewer. Plan
your route and your needs for sanitary sewer.
and Support Structures
Any equipment that needs to be located on a
mezzanine or support structure requires a proper engineered
analysis of the load on the support members. Placing a
Cooling Tower on the roof will require an analysis of the
roof structure to determine if it can support the weight.
Any support structure must be designed for
operating weight, start-up torques and wind and snow loads.
The most important aspect on pipe
installation is to ensure that the pipe is large enough to
minimize pressure losses through the system and provide the
proper flow to all processes.
A common guideline is to use the lesser of
either a maximum velocity of 10 fps or a pressure loss of 10
ft per 100 feet of pipe. In longer pipe runs, you may want
to adapt a lower guideline. For gravity return pipe, a slope
of 1” per 10 feet is recommended and a velocity less than 4
Plan your route to avoid obstructions like
cranes and support columns. Ensure that the pipe is not
obstructing forklift routes or are in danger of being hit.
Calculate the weight of the pipe filled with
water and make sure your roof/columns can support the weight
(see structural engineer).
Common pipe material used are sch40 steel,
sch80 PVC, copper, and stainless steel.
The limiting factor on using sch80 PVC is the
water temperature. If your water temperature can climb to
110ºF or warmer, the pipe becomes soft and can start to sag
creating weak points at the joints. Sch80 PVC has the
advantage of being low cost and not rusting. However, making
any repairs or changes will require at least 8 hours for the
glue to set. It is recommended that isolation valves be
placed on sections that can be isolated for repairs or
changes without affecting the flow to the rest of the plant.
If you are using plastic valves, these valves must be
periodically used or they can stick eliminating their
usefulness when needed. Steel ball valves or butterfly
valves are an ideal replacement for plastic valves.
Sch 40 Steel can be susceptible to rust. The
cooling water must have rust inhibitors and stay filled with
water to reduce the impact of corrosion.
Copper pipe in small sizes ( ½” to 1 ¼” ) is
an ideal replacement for small plastic pipe. PVC pipe in
these sizes are not rigid enough and require additional
support. Also if the process has a high return water
temperature (like air compressors), you would want to avoid
using plastic pipe for the return drops.
Thin wall stainless steel pipe can also be an
alternative if you do not want to use steel pipe or require
something more durable than PVC pipe. Thin wall stainless
steel is only nominally more expensive than steel piping and
can handle more corrosive water.
Some cooling equipment requires field
refrigeration piping between components. Most common is the
refrigeration piping required between the outdoor condenser
and the chiller.
Refrigeration piping, like water piping, must
be sized to ensure minimal losses while keeping velocity
high enough to ensure refrigeration oil flow. (See proper
refrigeration pipe sizing charts.) Only proper refrigeration
copper pipe must be used. Once completed, a vacumn is
applied to evacuate any contaminants and to ensure no leaks.
Traps are also a consideration in proper refrigeration
piping. A qualified refrigeration mechanic is recommended
for refrigeration piping.
Check the quality of the power being
supplied. You may want to include phase protection.
Depending on the pipe installation, water
hammer may be an issue. Slow actuating valves, soft starters
or a water hammer arrestor are all solutions.
Check the quality of your make-up water. If
your make-up water is too hard, you may want to install a
water softener. Check with your local water experts.
START-UP OF COOLING EQUIPMENT
Whenever possible, the use of a factory
approved start-up technician is recommended. Before
start-up, make sure you have a copy of the Installation,
Operation and Start-up Manual. Review that the installation
is completed before start-up and a cooling load is
recommended to allow the equipment controls to be adjusted
for the applications. If available, a copy of the factory
test sheet is also recommended.
Some things that are part of the start-up:
Power on. For chillers, power is required
for at least 8 hours before start-up.
Rotation. For pumps and fans, power
connected incorrectly will cause the pump or fan to turn
Amp Draw. By measuring the amp draw, you
can determine if a motor may be faulty or the wiring is
Control wiring. Make sure that all sensors
are wired back to the controller and that the sensors are
Pressures and flows. Too much or not enough
flow and pressure through a chiller evaporator, a chiller
water-cooled condenser, a dry fluid cooler, or a Cooling
Tower can cause the unit not to operate properly.
Refrigeration Pressures. Reviewing the
refrigeration and oil pressures and comparing them to the
factory test sheet will ensure the equipment is operating
Controllers timers and set points. These
must be tuned for the system and should ideally be done
when the process is running. A second visit may be
Training. Authorized plant personnel and a
local contractor should be part of the training. Training
should include start-up, servicing, maintenance and
Get a list of recommended spare parts based
on the maintenance upkeep. Also, get a list of how long it
would take to get the major components in case of a major
failure. This way, you can plan your alternatives.
Example of a Mechanical Room Layout