Installing Chiller Systems: Chapter 2
Unit Handling Part 1
By the end of this module, you should be able to: Inspect the delivery of chillers, Explain types of hoisting, and Describe handling of chillers during positioning. Skip to quiz!
Delivery Inspection
Small equipment such as TV, ovens, AC, and mobile phones can be delivered easily. But, large equipment such as a couch, wardrobe, and bed requires more than one person to lift and shift. Similarly, chillers are delivered at a site using various tools and techniques.
Chillers are delivered to the site very early, even before the mountings are prepared. Before using or installing large equipment, we keep them in a safe place to prevent any damages. Similarly, we do it for chillers keep them in a safe place before installation.
As soon as we receive any new item, we inspect whether it is working correctly, are there any damages. Similarly, we need to check chillers at the time of delivery using the delivery note provided along with it. Let’s see what is to be inspected at the time of delivery.
Some of the points of unit inspection using a delivery checklist are as follows:
Inspect panels and controls,
Open and inspect loose equipment and crate(s),
Inspect unit plates or labels,
Inspect valves (if applicable) and pipes, and
Damaged and missing parts must be noted on the delivery note and at the time of receipt.
Chillers shipment depends upon the type of chiller used and its capacity. Chillers shipment types are:
Single unit shipment or Assembled shipment, and
Multiple shipments or parts shipment.
For small chillers, a capacity of up to 200 tons single unit shipment is used.
Chillers are delivered in three or more parts for larger tonnage. For example, Consider a water-cooled chiller consisting of four parts. Parts of water-cooled chillers are:
Condenser,
Evaporator,
Compressor, and
Control panel.
Rigging & Hoisting
Chillers are heavier, lengthier, and difficult to move, so positioning requires rigging and hoisting. Some of the general methods are:
Forklift,
Hoisting,
Crane,
Rigging, and
By unloading team.
Rigging contractors serve the job of moving from one place to another. A rigging and hoisting contractor can handle the job with the help of workers without any danger or damage to the chiller. Let’s learn how the hoisting is used to lift the chillers.
Hoisting is the process of lifting equipment using various tools. Crane hoisting a chiller is carried out using a spreader and rigging. The tools used for hoisting are simpler to use, such as hooks, Shackles, wires, ropes, and spreaders.
Important points to be kept in mind when installing chillers are:
Never lift or sling the chiller with devices fastened to the top frame structure,
Lift the chiller only from the bottom (sometimes from the top),
Before hoisting, the rigger must ensure that the load is balanced correctly to prevent tilting or tipping of the chiller,
Test the load before lifting it off the truck or ground,
Hoisting or moving heavy equipment should only be done by competent rigging and hoisting contractors,
Never allow personnel to go under the unit while it is in the air, and
Failure to follow safety instructions could result in permanent injury or loss of life.
Types of Hoisting
The list of hoisting methods used for chillers are:
Hooks,
Ropes & cables,
Spreader,
D-Shackles,
Chain pulley,
Rollers and dollies.
Let’s look at all these types in brief.
Hooks are similar to shackles, but they are locked with springs, not manually. Hooks are simpler in use, and cranes have these to lift equipment. Hooks vary in size and capacity, and their use depends on the weight to be lifted.
Specially made high-quality ropes and cables are used to lift chillers. Rigging ropes have hooks at the end to connect and tighten them across the chillers.
A spreader prevents the chiller from being damaged while hoisting. Chillers manuals provide how to use the spreader in order to prevent any damages. Spreaders are available in various sizes, and it depends on the chiller to be lifted.
Shackles assist in connecting ropes and cables with the unit. They have lock pins at the end, which are being tightened during lifting or shifting. There are many types of shackles, but D-shackles are used widely.
Chain pulleys are a form of manual lifting in place of cranes. Chain pulleys consist of a hook and a chain to lift the equipment. The ropes and cables are tied around the unit and placed in a hook for lifting. The chain pulley is useful in lifting the equipment for smaller heights.
Rollers assist in moving the equipment by pushing. They are placed below all the ends or corners of the chiller. Once placed, they can be moved easily by pushing. Rollers are also called dollies.
The lifting and positioning of the chiller is the main task in chiller installation. Crane, forklift, sliders, chain pulley, and many more are used while lifting the equipment. Rigging contractors will inspect the site first then deploy their team for work.
For example, consider a chiller has to be placed in plant room below the roof. The chiller is hoisted using a tower crane. The tower crane is deployed first, and the chiller is brought to lift. Chillers have built-in holes on the frame or support channels to lift.
The sequence would be:
Use of cables or ropes to hoist,
Connecting the hooks, spreader, and D-shackles,
Lifting, and
Positioning.
Now, we have successfully placed the chiller on mountings.
Chillers are inspected using a delivery checklist. Chillers are placed on the mountings with the help of rigging contractors. There are several hoisting methods, but a spreader is used while lifting a chiller to the roof.
Unit Handling Part 2
By the end of this module, you should be able to: Describe how to install vibration isolators, Use a torque wrench on chillers, and Describe how to assemble a chiller provided in parts. Skip to quiz!
Vibration Isolators
Have you ever thought about why vibrations occur in equipment? Can we prevent vibrations from occurring in a system? We have seen large machines such as trucks, trailers, and airplanes make huge noises and vibrations.
Mechanical vibrations and vibration-induced noise are common in chillers due to large-capacity compressors. If a generator is on and moving on the floor, we will use a mat or rubber pad below it to prevent moving. Let’s now find what is used to stop these vibrations in chillers?
Vibration is caused by rotating motion from the components within the chiller. Vibration isolators prevent the transmission of vibrations into the structure. Chillers are connected using flexible connectors for pipes, wires, and sensors to prevent these vibrations.
Vibration isolators reduce the vibrations in the mountings and prevent vibrations from affecting the connections to the chiller. It is achieved by using special mounts designed to absorb the vibration or movements. There are many types of vibration isolators depending upon weight, but the simplest one is a rubber pad.
The types of vibration isolators used for chillers are:
Neoprene rubber pads,
Floor isolator or hanger,
Spring floor isolator,
Restrained spring isolator,
Air isolator, and
Seismic isolator.
Every chiller has its pre-defined vibration isolator by the manufacturer.
Rubber Isolators: Single-ribbed or crossed, double-ribbed elastomer-in-shear pads, in combination with steel shims when required, having minimum static deflections. These are the simplest ones used in residential AC and VRF also.
Spring Isolators: It consists of a spring coil with adjustable torque as per the weight loaded, and it is used specifically for dynamic or unstable loads. Water-cooled and air-cooled chillers use spring isolators in different forms as per manufacturer guidelines.
Mounting locations for each model configuration are found in the dimensional drawings or submittals drawings, available from a manufacturer representative. Submittal drawings also specify the correct isolator color or size for each mounting location, if ordered with the unit.
Spring isolators are installed at the time of unit positioning or fixed previously before unit installation. Isolator springs should not be loaded until all unit installation tasks are complete. Next, the springs should be adjusted to the vendor-listed compression load point.
At last, loading tightens the isolator bolts, removes seals or wood pieces, and does not overtighten the mounting bolts. Overtightening may result in cracking of the isolator housing and will impact the isolation effect.
Bolts are tightened with required torque to prevent leakage and loss of bolts. The torque required to tighten the bolts of chiller connections, mountings, and power connections, depends on the manufacturer to provide recommended torque. The evaporator and condenser coverings are provided with bolts to ease assembling and maintenance.
Tightening or re-tightening must be done using the torque wrench tool and as per the manuals. Recall that the torque wrench tool has a load setting to achieve the required torque. The torque wrench tool tightens the nut clockwise and stops the tightening when a click sound appears.
Chiller Assembly
Have you ever seen the assembly of an airplane? Can we do the same for the chillers? Can you provide the names of some of the large assembled machines?
Water-cooled chillers are installed in the plant or mechanical room, unlike air-cooled chillers on the roof. Chillers ranging from 200 to 2000 tons are heavier and oversized. Large-sized chillers consist of three or more sections, which can be assembled and disassembled.
There are several reasons to use a chiller in parts for installation, such as:
Retrofit of chillers,
Handling issues,
Transporting issues,
Replacement of a component, and
Plant room restrictions.
Let’s consider an example of a large wardrobe, which is provided in pieces and assembled at home or apartment. Similarly, large chillers are shipped in multiple parts and assembled at the site. In several cases, chillers have to be passed through the limited size doors or spaces.
Let’s consider a medium-sized water-cooled chiller with four parts. The parts of a water-cooled chiller are:
Evaporator,
Condenser,
Compressor, and
Control panel.
Let’s now discuss how to assemble all these components.
The chiller parts are positioned according to the manufacturer’s guidelines. Assembly of parts requires necessary connections like pipes, wiring, sensors, control panel, fixing them with bolts and connecting between them. Let’s continue with the previously discussed chiller that consists of four parts and assemble it.
The common procedure followed is;
Inspect the site where a chiller is required to be installed as per approved drawings,
Check whether the chiller delivered at the site consists of all four parts as per the manual,
Identify the sequence of chiller assembly and installation requirements,
Make a list and proceed with the installation with all safety requirements.
Let’s consider the previous chiller and the sequence of parts followed are:
First- Condenser
Second - Evaporator
Third - Compressor
Fourth - Control panel
We’ll proceed with it, and the positioning of the chiller will be done as described in previous slides.
The installation consists of:
Use of hoisting and rigging,
Position the first part (Condenser) and place it at the required location,
Next, place the second part (Evaporator) and place it beside the condenser and tighten the bolts with a power wrench.
Then, position the third part (Compressor) on the condenser and tighten all the bolts provided.
Finally, position the fourth part (Control panel) and tighten the bolts.
Now the chiller is inspected as per the manufacturer manuals.
Now the chiller is assembled!
Once the chiller is assembled the chiller needs to be inspected. It is to ensure that there is no leakage or lose connection. Before proceeding with any other chiller connections, the assembly inspection must be carried out first, and the document must be maintained.
Some of the steps are:
Check the parts are installed in the correct position,
Check for any loose nuts & bolts between assembled parts,
Check for any damages on the assembled chiller, and
Finally, we can proceed with chiller connections.
Now! we are ready to fix the chiller connections.
Vibration isolators reduce the vibrations in the mountings and prevent vibrations from affecting the chiller connections. Large chillers are provided in parts that can be assembled at the site to ease handling and transportation. The assembled chillers should be inspected soon after assembly to ensure no leakage and lose connections.
Question #1: Chillers are inspected using a/an ________ at the time of unit delivery.
Delivery checklist
Forklift
Manifold gauge
Chiller diagram
Scroll down for the answer...
Answer: Delivery checklist
Chillers are inspected using a delivery checklist at the time of unit delivery.
Question #2: Select the minimum items to be checked at the time of delivery of a chiller. (Select all that apply)
Break seal
Inspect panels
Open valves
Check for damage and missing parts
Scroll down for the answer...
Answer: Inspect panels
Check for damage and missing parts
Checklist for the minimum items to be checked at the time of delivery of a chiller are:
Inspect panels.
Inspect evaporator plates.
Inspect valves (if applicable) and piping.
Check for damage and missing parts.
Open and inspect loose equipment and crate(s).
Question #3: Can you list out the methods used to lift heavy objects?
Forklift
Pulling
Hoisting
Elevator
Scroll down for the answer...
Answer: Forklift
Hoisting
Some of the general methods are:
Forklift,
Hoisting,
Crane,
Rigging, and
By unloading team.
Question #4: Chillers are heavier, lengthier, and difficult to move, so positioning requires: (Select all that apply)
Packaging unit
Rigging
Wire connectors
Hoisting
Scroll down for the answer...
Answer: Rigging
Hoisting
Chillers are heavier, lengthier, and difficult to move, so positioning requires rigging and hoisting.
Question #5: Chillers are installed on the roof using?
Elevator
Crane
Forklift
Helicopter
Scroll down for the answer...
Answer: Crane
Chillers are installed on the roof with the help of a crane of the required capacity.
Question #6: Point out where to connect hooks for a chiller.
Condenser
Hook holes
Compressor
Side pipes
Scroll down for the answer...
Answer: Hook holes
Holes to connect hooks on a chiller.
Question #7: Which equipment is used to prevent a chiller from damage while lifting?
Hook
Safety harness
Spreader
Ropes
Scroll down for the answer...
Answer: spreader
The spreader is used while lifting a chiller so that the coils or parts are not damaged.
Question #8: D-shackles are used to connect _____ & _____.
Mountings
Cables
Spreader
Ropes
Scroll down for the answer...
Answer: Cables
Ropes
D-shackles are used to connect the cables and ropes.
Question #9: Which device is used to prevent the vibrations caused in a chiller?
Rollers
Leveling tool
Insulating material
Vibration isolators
Scroll down for the answer...
Answer: Vibration isolators
Vibration isolators reduce the vibrations in the mountings and prevent vibrations from affecting the connections to the chiller.
Question #10: Select the different types of vibration isolators. (Select all that apply)
Scroll down for the answer...
Answer: Rubber pad
Spring Isolators.
The different types of vibration isolators are:
Rubber pad, and
Spring Isolators.
Question #11: Select which of the following is a rubber isolator?
Scroll down for the answer...
Answer: Rubber pad
Question #12: Select which of the following is a spring isolator?
Scroll down for the answer...
Answer: Spring isolators
Question #13: Where is the vibration isolator installed in chillers?
Between valves
At the base
Above the chiller
On the side surface
Scroll down for the answer...
Answer: At the base
Vibration isolators are installed at the base of a chiller. Spring isolators are installed at the time of unit positioning or fixed previously before unit installation.
Question #14: Which tool is used to provide the torque required to tighten the bolts of chiller connections?
Torque wrench
Double wrench
Pliers
Allen key tool
Scroll down for the answer...
Answer: Torque wrench
The torque wrench tool provides the torque required to tighten the bolts of chiller connections, mountings, and power connections.
Question #15: Select the best reasons why a chiller in parts is preferred for installation. (Select all that apply)
Difficult to assemble
Retrofit issues
Isolators issues
Handling issues
Scroll down for the answer...
Answer: Retrofit issues
Handling issues
There are several reasons to use a chiller in parts for installation, such as:
Retrofit of chillers,
Handling issues,
Transporting issues,
Replacement of a component, and
Plant room restrictions.
Question #16: Select the parts to be assembled for a water-cooled chiller.
Scroll down for the answer...
Answer: Evaporator
Compressor
The parts of a water-cooled chiller to be assembled are:
Evaporator,
Condenser,
Compressor, and
Control panel.
Question #17: Select the correct sequence of inspection.
Connecting the parts
Placing the parts as per the sequence in manuals
Use of hoisting and rigging
Inspecting after assembly
Scroll down for the answer...
Answer: Use of hoisting and rigging,
Placing the parts as per the sequence in manuals,
Connecting the parts, and
Inspection after assembly.
Sequence: 3,2,1,4
Use of hoisting and rigging,
Placing the parts as per the sequence in manuals,
Connecting the parts, and
Inspection after assembly.
Question #18: Select the correct sequence of inspection.
Check for any loose nuts & bolts between assembled parts
We can proceed with chiller connections
Check for any damages on the assembled chiller
Check the parts are installed in the correct position
Scroll down for the answer...
Answer: Check the parts are installed in the correct position,
Check for any loose nuts & bolts between assembled parts,
Check for any damages on the assembled chiller, and
We can proceed with chiller connections.
Sequence: 4,1,3,2
Check the parts are installed in the correct position,
Check for any loose nuts & bolts between assembled parts,
Check for any damages on the assembled chiller, and
We can proceed with chiller connections.