Croydon Hospital Chiller Refurbishment
CASE STUDY
Extending chiller life and reducing capital expenditure at Croydon University Hospital
Project overview
The University Hospital in Croydon is one of the area’s principal healthcare facilities. Home to the emergency department and more than 100 specialist services, including 24/7 maternity care, the hospital provides essential support to residents across both the north and south of the borough.
As with all NHS Trusts, maintaining reliable infrastructure while managing budgets efficiently is a continual priority. When a recurring issue threatened the performance of two RHOSS chillers, the hospital turned to LH for expert analysis and support. Its expert advice led to the prevention of an ongoing repair issue, efficiency improvements and the extended lifespan the critical cooling system.
The Challenge
The hospital’s RHOSS TCAEQY 2220 chillers, originally supplied by Klima-Therm in 2016, had experienced repeated condenser coil failures.
Over an eight-year period, the condenser coils had required replacement twice, with each replacement costing approximately £50,000. The accepted explanation was that the chillers’ proximity to the hospital mortuary was causing ‘excessive corrosion’.
"We could have simply replaced the condenser coils and walked away, only to repeat the same process when the chillers failed again a few years later. Our clients work with us because we focus on providing the right advice, however. Our priority is ensuring HVAC systems operate as they should, deliver maximum efficiency and achieve the longest possible service life." – Paul King, Project Sales Manager at LH
When a further condenser coil replacement was required, LH Project Sales Manager, Paul King, was asked to provide a quotation. Rather than simply replacing the failed components, Paul questioned whether corrosion alone could explain the recurring problem.
Drawing on its extensive HVAC expertise and specialist knowledge of RHOSS equipment, LH conducted a comprehensive survey of the chilled water system. While the condenser coils were indeed leaking, the investigation identified a more fundamental issue. The chillers were short cycling, causing the compressors to start and stop far more frequently than intended.
This excessive cycling created abnormal mechanical stresses within the compressor assemblies, resulting in repeated twisting and movement that accelerated wear on condenser coil joints. Over time, the joints became fatigued, leading to leakage and eventual failure.
Further analysis revealed that the primary chilled water system contained significantly less water volume than required for stable operation, creating the conditions that allowed the short cycling to occur.
“LH has provided consistent support and technical expertise throughout the project at Croydon University Hospital. “Their advice to install a buffer vessel has led to long-term savings, extending asset life, and improving energy performance. Rather than simply replacing failed components, LH took the time to investigate the underlying cause of recurring condenser coil failures identifying an issue that had previously gone undetected. “Paul King put forward a practical, long-term solution that addressed the root cause and improved the stability of the chilled water system - a critical piece of the hospital infrastructure - delivering both operational and financial benefits. “I am impressed with their attention to detail and commitment to problem solving. We will be working with LH on similar projects in the future.” – Matthew Goodard - Senior Project Manager - Croydon Health Services, NHS Trust
Key benefits:
- Prevention of recurring condenser coil failures
- Avoidance of £50,000 in replacement costs every four years
- Extended operational life of the chillers
- Reduced risk of complete plant replacement, potentially avoiding capital expenditure of approximately £250,000
- Improved system reliability and uptime
- Enhanced energy efficiency and reduced operating costs
- Long-term protection of critical hospital infrastructure
Our Solution
Rather than replacing condenser coils yet again and treating only the symptom, LH recommended addressing the root cause of the problem. To increase system volume and stabilise operation, two buffer vessels were installed within the chilled water system.
Benefit to the Client
By eliminating the short cycling issue, the hospital could avoid repeated condenser coil replacements and significantly reduce the risk of a complete chiller failure, protecting both its budget and critical cooling.