How to Conduct Chiller Maintenance
The first step is to make sure the customer understands why it’s important
There is a laundry list of chiller types in the installed base, but all of them have one thing in common: The equipment requires maintenance. Depending on the type of chiller and the time of year, contractors can find themselves working on an annual maintenance call, seasonal start-up service, an inspection service, or shutdown service. Contractors not only deal with the equipment, but they also have to help make the customer understand the importance of chiller maintenance. How does a contractor accomplish these tasks successfully?
GET THE CUSTOMER ON BOARD
Customers who just spent thousands of dollars for new equipment can often be a tough sell when it comes to maintenance agreements. The key is getting the customer to understand the significant cost difference between preventive maintenance and chiller failure repair.
“We go over in detail how regular and predictive testing can benefit our customers and the chiller over its life cycle,” said Jeff Terrill, service manager for Integrated Facility Services, St. Louis.
“The first thing we discuss is the energy saved by keeping their chiller running in top working condition. Explaining this goes a long way to demonstrating the value of proper chiller maintenance.”
Adam Kloehn, regional HVAC service manager, Bassett Mechanical, Kaukauna, Wisconsin, said that reviewing failure history, age of equipment, its run time since last teardown, or eddy current testing are items that should also be a part of the conversation with customers.
“The customer benefits from more production uptime, increased energy efficiency, and the prevention of catastrophic failure of major components like the compressor or evaporator/condenser coil,” he said. “When we perform chiller maintenance, our customers realize we are a one-stop shop — one vendor to take care of all their needs.”
TOOL AND TRAIN
With so many types of chillers, contractors can find that once the customer is on board, there is a lot more work to be done. Terrill said that there is an investment that has to be made in terms of time and money to purchase and maintain all the tools and software needed. Kloehn agreed that the tool investment is significant, and he also pointed out that there is an equally significant investment in training.
“A proactive annual training plan needs to be in place, which includes manufacturer-specific training,” he said. “Maintenance per chillers differs from manufacturer to manufacturer. This includes separate trainings for general chiller maintenance and teardown chiller maintenance per manufacturer.”
Terrill added that contractors will also have to train technicians for newer versions of earlier models that a technician may have trained on previously.
“This adds up to a significant amount of training over time,” he said. “A dedication to and passion for learning these machines is required of your team as well.”
MAINTENANCE HOW TO
With the customer on board, the tools in house, and the ongoing training in place, it’s time for technicians to get to work servicing chillers. Atomatic Mechanical in Arlington Heights, Illinois, provides maintenance to all types of chillers across six counties within the Chicago area.
“We provide annual services, yearly start-up services, and periodic ‘running’ inspections where we perform an extended inspection and review the customer’s maintenance team’s logs,” said Don Kaslofski, vice president of Service, Atomatic. “We often identify a changing trend before it interrupts operations. Periodic maintenance provides insight into the chiller’s condition by a qualified technician. It allows us to be proactive and ensure reliability and efficiency.”
For those working on centrifugal chillers, Kaslofski suggests following these procedures for an annual inspection:
- Test electrical — Tighten terminals within the main leads, starter, and control panels. Record Meg ohm readings of compressor motor and oil pump.
- Pressurize and leak check machine — Atomatic performs this service whether the machine is a low-pressure unit (R-11 and R-123) or a positive pressure machine (R-134a, R-22, or others). This is done by heating the evaporator water bundle with a supplementary heater and pump. It brings the low side to a higher pressure than during operation and allows for thorough leak testing.
- Test and calibrate controls — Test all operation-related controls (flow switches, freeze and temp sensors, transducers, etc.). Record settings and verify they are accurate.
- Sample oil (if applicable) and change unit filters — This practice allows the chiller to begin the next season with fresh filters on both its refrigeration and oil circuit, ensuring proper operation.
- Perform purge system maintenance (low pressure machines only) — This procedure removes non-condensable gases that can be introduced to the chiller on the low pressure side, where there’s a filter, a pump, and possibly a refrigeration circuit.
- Clean the condenser tube — This service requires technicians to open, mechanically brush and flush, and then reinstall the removed water-side items of the chiller’s condenser.
After finishing the annual maintenance list, the machine is ready to be put back into service.
Seasonal start-up service requires working with the building engineer and/or maintenance team on-site to inspect, clean, and verify the proper condition of the cooling tower fan and water-side systems, according to Kaslofski.
“Technicians will also need to verify that proper pumps and flows are attained on both the chilled and condenser loop,” he said. “Once system flow is established, the machine is put into operation.”
With the equipment in operation, Kaslofski suggests that technicians verify and record the following:
- Heat transfer (refrigerant/water temperature comparisons) on both the evaporator and condenser sections.
- Electrical volts, amps, etc.
- Temperature settings on system, chiller, tower, etc.
- Tonnage being produced compared to the electricity being consumed, to ensure the entire system is performing at optimum efficiency.
Despite the time, money, and resources, there are benefits for contractors who invest in chiller maintenance. One of those benefits is the improved customer perception of the company.
“Our chiller maintenance services mean everything with respect to the relationship we maintain with our customers,” said Kaslofski. “We are seen as a partner and not a solicitor.”
Another benefit is the opening of opportunities to service a client’s additional chillers as well as an entire building’s HVAC equipment, said Terrill.
“The best part is your customer knowing they can count on you to provide the very best chiller service they can get,” he added.
Publication date: 7/1/2019