Chiller Maintenance Checklist
Category : Articles
News Article No.1
Introducing the first in a series of in depth news articles, this time featuring the chiller maintenance checklist. This article has been written with you- the customer in mind. Read below for practical advice on how to keep your chillers in the best condition.
Each day when you walk round, you can check to see if your plant is starting to malfunction. Become accustomed with the usual readings to help you diagnose the faults.
Here are the things to check for and how to remedy them:
Water System Pressure
Keep an eye on the pressure in the water system.
Small Chiller Maintenance Checklist
On a small chiller, there will be a water outlet pressure gauge. Make a mark on the gauge where the pressure is when the chiller is in good working order. You can use this mark to notice if the pressure is starting to drop off.
Strainer
The most common cause for low water system pressure is a blocked strainer. It is usually a ‘Y’ type with a bolted fitting. With the chiller off and the water system valves closed, unscrew it and check for debris. If it is blocked, make a note of how long it took to block, then add the cleaning of the strainer into the periodic maintenance schedule.
Pump
Ensure the pump rotation is correct by checking that the cooling fan is sucking into the pump. If it is going backwards: isolate electrically, then swap any 2 of the 3 phase wires. Brush down the inlet to the cooling fan to ensure good air flow and a cool pump motor.
Large Chiller Maintenance Checklist
On a large chiller, the water system pressures may be available in the controller- have a look through the menus. The pressure will be measured in bar. Another popular method on a large chiller is a flow meter. This may be a stand alone device on the chiller panel, or on a control panel nearby. It will read in m3/hr. Check to see if the pressure or flow is lower than usual. If so, ring one of our trained professionals.
0161 370 7193
service@maximuschillers.com
Water System Temperature
The chiller should be:
- Matching the load and running continuously.
- Loading and unloading in sequence with other chillers.
- Going through a cycle and achieving set point.
In any case, you will become accustomed with the usual chilled water temperature according to varying load conditions. If the plant is struggling to achieve set point, or is running higher than usual- this is a sign of system faults.
Walk along the chillers that feed the same water system and make a log of the faults showing on the controllers.
Here are the things to check for high water system temperature:
Small Chiller Maintenance Checklist
Low Refrigerant Pressure
If it has a low pressure gauge, look to see if the pressure is lower than usual. If so, this is a sign of refrigerant shortage in the plate evaporator. A scheduled visit from one of our trained engineers to carry out a pressure test can be arranged.
Breakers
Look for any breakers that have tripped in the panel. One reset can be carried out by a qualified onsite electrician. If the fault reoccurs- ring our support team. If the scroll compressor has tripped, check to see if the compressor is hot. If so, isolate and do not attempt a restart.
Condenser
A blocked condenser will inhibit the rejection of heat. Brush it down and give it a rinse with water. A common occurrence onsite with some condenser designs is a panel being left off with the chiller running! This happens when the onsite engineers are fault finding another issue with the chiller. The fans will suck through the opening as this is the easiest path. The gauge will be higher than usual as the condenser builds in pressure. A high pressure switch trip out will occur.
High Pressure Switch
To locate the switch- first identify the discharge pipe. It is the smaller of the 2 pipes on the compressor. The high pressure switch will either be bolted onto the pipe, or a thin pipe will lead from the discharge to the frame of the chiller. In any case, you are looking for a small box with a button and a wire leading to the panel. Press the button and you should hear it click. If this fault reoccurs- ring our technical support desk.
Large Chiller Maintenance Checklist
Suction
Should there be a refrigerant shortage, the controller will display a pre alarm: suction limiting. This is the controller preventing the compressor from loading up to prevent a low pressure trip out in the shell and tube evaporator. As above, one of our team of engineers can be sent to site to resolve the issue.
Discharge
If the controller is showing: discharge limiting- this is a sign of a condenser issue. A full strip down and cleaning of the tubes may be required. Ring our technical support desk for further advice.
0161 370 7193
service@maximuschillers.com
Chiller Remote Monitoring
We at maximus chiller can install remote monitoring systems to your chillers so we can fault find and diagnose from a laptop. This means we can give you real time advice over the phone. Now you are accustomed with our chiller maintenance checklist- you can give feedback regarding the plant to assist our engineer.
Parts
For our contract maintenance customers: a range of commonly used parts are kept onsite to reduce downtime. We can give practical, step by step advice on the fitting of parts. We often carry out video calls with our customers, as chiller data plates, parts and components can be easier to show than describe.
Any Chiller- Any Problem- Any Part- Any Refrigerant- Anywhere- The MAXIMUS ADVANTAGE™
To read more about air cooled chiller maintenance click the Tag at the top of the page.
Related Articles:
Air Cooled Chiller Planned Maintenance
Process Chiller Maintenance Visit
Chilled Water System Maintenance
Air Cooled Chiller Maintenance
Centrifugal Chiller Maintenance
Industrial Chiller Maintenance
Air Cooled Chiller Condenser Maintenance
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