Cooling Tower Maintenance Checklist
Control legionella risk and maintain cooling performance with structured cooling tower checks — water treatment, fill pack condition, drift eliminators, and HSE L8 compliance.
What is a cooling tower maintenance checklist?
A cooling tower maintenance checklist is a structured list of the 12 preventive maintenance tasks — covering visual, functional, cleaning, safety and record-keeping checks — that keep a cooling tower running safely and reliably. It groups routine checks by frequency, from daily inspections to annual servicing, so FM teams and building engineers can plan and evidence preventive maintenance.
Core cooling tower checks
- Inspect drift eliminators for damage or displacement
- Check water treatment chemical dosing levels and biocide residuals
- Check basin/sump for sludge, debris, and biological growth
- Verify legionella control measures are in place and documented
- Record water temperatures, chemical levels, and microbiological test results
What is a cooling tower?
A cooling tower rejects heat from a building's cooling system to the atmosphere through evaporative cooling. Warm condenser water from the chiller is distributed over a fill pack while a fan draws ambient air through the tower, cooling the water through evaporation. Cooling towers require rigorous maintenance due to their legionella risk profile and are subject to statutory water hygiene controls.
This checklist is one of 34 in our HVAC maintenance checklists, covering air handling units, fan coils, chillers, VRF, ductwork and extract systems — filters, coils, refrigerant and damper checks.
Typical Cooling tower maintenance checklist
A practical starting point for planned preventive maintenance. Always refer to the manufacturer's O&M manual and site-specific requirements.
Visual Checks
- Inspect drift eliminators for damage or displacement
- Check fill pack condition for fouling, scaling, or biological growth
- Inspect water distribution nozzles or troughs for blockages
- Inspect casing and structural supports for corrosion or deterioration
Functional Checks
- Check water treatment chemical dosing levels and biocide residuals
- Test cooling tower water temperature and approach to wet bulb
- Inspect fan blades, bearings, and motor condition
- Check make-up water float valve and overflow
Cleaning & Housekeeping
- Check basin/sump for sludge, debris, and biological growth
- Clean strainer baskets and bleed-off valves
Safety Checks
- Verify legionella control measures are in place and documented
Record Keeping
- Record water temperatures, chemical levels, and microbiological test results
Download the free Cooling tower maintenance checklist PDF
Get all 12 tasks as a printable PDF — free, no signup needed. Keep a copy in the plant room, attach it to work orders, or share it with your maintenance contractor.
Typical maintenance frequency
Suggested intervals for cooling tower maintenance. Actual frequencies should follow manufacturer guidance and site-specific risk assessments.
Weekly
- •Check chemical dosing levels
- •Visual inspection for cleanliness
- •Record water temperatures
Monthly
- •Microbiological water sampling
- •Clean strainers and sump
- •Check drift eliminators
Quarterly
- •Full water system review
- •Fill pack inspection
- •Fan and motor check
Annually
- •Full tower clean and disinfection
- •Fan bearing and motor service
- •Structural inspection
- •Legionella risk assessment review
Common faults and issues
Issues to be aware of when maintaining cooling tower equipment.
Safety and compliance notes
Key safety considerations for cooling tower maintenance. This is general guidance only — always follow OEM instructions, statutory requirements, and your organisation's safe systems of work.
Reference standards and frameworks
- United Kingdom
- SFG20, CIBSE Guide M, and the UK F-Gas Regulations for refrigerant plant
- North America
- ASHRAE/ACCA Standard 180, plus EPA Section 608 refrigerant handling rules
Frameworks commonly referenced when planning cooling tower maintenance programmes. Always confirm the requirements that apply to your site and jurisdiction.
Managing Cooling tower documentation with PM Assist
PM Assist helps FM and building operations teams search their O&M manuals and building drawings in seconds. Upload your cooling tower documentation and ask questions like “What is the rated cooling capacity?” or “When was the last F-Gas leak check?” — and get source-cited answers instantly.
See PM Assist answer questions about a real cooling tower manual — try the live demo, no signup needed.
Take this checklist with you
Download the branded PDF, generate a custom version for your asset, or run AI search across all your building documentation.
Inspection checklists for this asset
Maintenance keeps the asset working; a statutory inspection records whether it currently passes. Both usually apply.
Further reading on cooling tower maintenance
Compliance topics for cooling tower maintenance
Frequently asked questions
Why are cooling towers a legionella risk?
How often should cooling tower water be tested?
What is an L8 risk assessment?
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- Source-cited answers for maintenance queries
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