St James Hotel and Club Reva

St James’s Hotel and Club, London

A seamless upgrade for a landmark Mayfair hotel

When the owners of St. James’s Hotel & Club in London’s Mayfair decided to replace the property’s ageing air conditioning system, the project presented a significant challenge. The five-star luxury hotel needed a complete upgrade of its heating and cooling infrastructure, while continuing to operate and maintain the high standards of comfort expected by its guests. Working alongside our partner Daikin, we delivered a carefully phased VRV replacement project that kept around 80% of the hotel operational throughout the installation, providing a modern, energy-efficient climate control system with minimal disruption.

Replacing an ageing system

Located on Park Place in the heart of London’s Mayfair, St James’s Hotel & Club occupies a heritage building that first opened in 1857 as a gentlemen’s members’ club for diplomats. Today, the boutique hotel offers 60 luxury guest rooms alongside a restaurant, bar and meeting facilities.

By 2025, the existing VRV system had been operating for around 17 years and was nearing the end of its working life. For a luxury hotel, maintaining reliable heating and cooling is essential, as Nicolas Monaglio, General Manager of St. James’s Hotel & Club explains. “As a five-star hotel, guest comfort is absolutely critical. The objective in working with Cleanheat was to replace the ageing system with a modern Daikin VRV installation that would improve reliability, efficiency and overall comfort while allowing the hotel to remain open.”

A carefully planned installation

We first surveyed the building during 2024 before securing the contract towards the end of 2025. Following a successful tender process, coordinated by Saturn Imagineering, we were awarded the contract under a JCT. Installation began in February 2026 and was completed on schedule in July. Rather than closing the hotel completely, the works were carried out on a floor-by-floor basis.

Our team initially completed the upper floors before progressing down through the building, with reception, restaurant and bar areas incorporated into the programme. “We closed around 20% of the hotel at any one time,” Cameron Gray, Head of Business Development at Cleanheat explains. “That meant the hotel could continue trading while we completed a full replacement of the air conditioning system.” Each section took around three weeks to complete, allowing the hotel to retain the majority of its room occupancy throughout the project.

One of the biggest challenges involved replacing the outdoor VRV condensers located on the hotel’s rooftop. A conventional approach would have required multiple road closures and cranes to remove and replace the equipment, creating significant cost and disruption in one of London’s busiest districts. Instead, Cleanheat proposed dismantling both the old and new condensers into individual components that could be transported through the building before being assembled on the roof. “We proposed a strip-and-build approach,” Cameron explains. “Rather than using cranes, we dismantled the equipment into individual components and rebuilt everything on the roof. That significantly reduced disruption and was one of the reasons we won the project.”

In total, the project included the installation of 11 new Daikin VRV outdoor units, together with completely new indoor units and refrigerant pipework throughout the hotel. Existing pipework above corridor ceilings was replaced, while new access hatches were created to improve future servicing and maintenance.

“It’s effectively a completely new system,” Cameron says. “The outdoor units, indoor units and all the connecting pipework were replaced, giving the hotel a modern installation that’s designed for the long term.

Simultaneous heating and cooling across rooms with different orientations and demands is essential for a property such as a hotel, with recovered heat moved from spaces being cooled to spaces needing heat. Cameron again; “The new Daikin VRV system allows individual room control, enabling guests in different bedrooms to select their preferred heating or cooling settings independently.”

Minimal disruption for guests

Maintaining hotel operations throughout the project required close coordination between our installation team and hotel management. Between four and eight of our engineers worked on site each day, with noisy activities restricted to agreed daytime hours and additional weekend working helping maintain programme milestones.

For Nicolas and the hotel’s maintenance team, one of the biggest successes was how smoothly our installation progressed. “Cleanheat were very accommodating throughout the project. Noise was minimal and there was very little disruption considering the scale of the work. Early discussions had suggested cranes would be needed to access the rooftop equipment. Initially we thought there would be road closures and cranes, but Cleanheat found another way of doing it and assembling everything in situ, actually on the roof, made a big difference.”

Proven performance without compromise

The new Daikin system was put to the test almost immediately after completion during one of the hottest periods of the summer. “We went through the heatwave with no complaints,” says Nicolas. “Every room had the air conditioning running and the system performed exactly as it should.”

Guest feedback has also been positive, while the hotel’s maintenance team has found the new controls straightforward to operate. “So far everything has worked very well,” Nicolas adds. “The central controller is easy to use and gives us excellent control over the whole system.”

For us, the project demonstrates how major HVAC upgrades can be successfully completed within occupied hospitality environments without compromising guest experience. “We surveyed the building thoroughly before we started and that preparation meant we met every deadline,” Cameron says. “We’ve delivered a completely new Daikin VRV system while allowing the hotel to continue operating throughout the project.”

By combining our detailed planning, innovative installation techniques and Daikin’s VRV IV+ heat recovery technology, the project has provided St James’s Hotel & Club with a modern heating and cooling solution that delivers improved reliability, greater operational efficiency and year-round comfort for guests, while demonstrating how complex retrofit projects can be successfully delivered in prestigious occupied buildings.

The end result

Nicolas Monaglio, General Manager, St James’s Hotel & Club says “We went through the heatwave with no complaints. Every room was running air conditioning continuously and the system performed exactly as it should.”

This case study was originally published by Daikin and has been adapted by Cleanheat.

The Taj Group

Commercial,Hotels