Commercial HVAC case studies
What a joined-up commercial HVAC strategy actually delivers: an R410A VRF office moved to low-GWP R32, a hospital chiller and AHU refurbishment brought fully F-gas compliant under PPM, and a hotel electrified with heat pumps and rooftop solar. These are illustrative composites, clearly labelled — no named client, no fabricated review.
R410A VRF replaced with low-GWP R32 across a 6-floor city-centre office
- System
- 3 heat-recovery VRF systems on R32
- Indicative annual saving
- ~£14,000/yr in energy and eliminated reactive re-gas/call-out cost
- Payback (modelled)
- ~8 yr
The scenario
A managing agent ran a 5,500 sqm multi-let office on ageing R410A VRF that was leaking, out of warranty and increasingly costly to re-gas as R410A prices climbed. Tenants complained of hot-and-cold zones, and the agent needed to protect the building's lettability against the tightening MEES standard.
The measures
3 heat-recovery VRF systems on R32, ~130 kW total cooling, 48 indoor units, new controls and BMS integration
The outcome
Removed R410A stranding risk and recurring leak/re-gas cost, cut zone complaints, and lifted the building's modelled energy performance ahead of the proposed EPC B 2031 standard. Full expensing delivered a 100% first-year capital deduction. Staged floor-by-floor to keep the building let and occupied throughout. (Illustrative composite based on typical VRF-transition projects.)
Chiller replacement + AHU refurbishment at a Midlands hospital wing (PPM-led)
- System
- 1 low-GWP (R32) air-cooled chiller
- Indicative annual saving
- ~£31,000/yr energy + avoided reactive call-outs; downtime cut sharply
- Payback (modelled)
- ~9 yr
The scenario
An NHS estates team ran an end-of-life air-cooled chiller and two 1990s AHUs serving a hospital wing with a year-round cooling and ventilation demand. Reactive breakdowns were rising, and the six-monthly F-gas leak checks were being missed under a patchy reactive-only arrangement.
The measures
1 low-GWP (R32) air-cooled chiller, ~450 kW, plus EC-fan and heat-recovery refurbishment of two AHUs; six-monthly PPM contract with remote monitoring
The outcome
Statutory F-gas leak checks and records brought fully compliant under PPM; free-cooling and part-load control cut chiller energy; AHU EC-fan retrofit slashed fan power and improved ventilation air quality. The refurbish-don't-replace AHU decision saved a large share of the capital. (Illustrative composite based on typical public-sector HVAC upgrades.)
Gas boilers to air-source heat pumps + rooftop solar at a hotel (electrification)
- System
- 220 kW cascaded air-source heat pumps replacing the gas boilers
- Indicative annual saving
- ~£19,000/yr vs prior gas + grid cost after solar self-consumption
- Payback (modelled)
- ~9 yr
The scenario
A 90-bedroom hotel with ageing gas boilers, VRF cooling and a year-round heating and hot-water demand wanted to cut carbon for its ESG commitments and stabilise energy costs. The board asked whether it could electrify heat without the running cost rising.
The measures
220 kW cascaded air-source heat pumps replacing the gas boilers, integrated with existing VRF and a ~60 kWp rooftop solar array; MVHR upgrade on the leisure and function spaces
The outcome
On-site combustion cut ~85%, ~50 tCO2 saved per year; solar offset the heat-pump electricity draw so running cost held flat despite the electricity:gas gap; MVHR heat recovery reduced the ventilation heat penalty. Funded via full expensing; no reliance on the domestic-only Boiler Upgrade Scheme. (Illustrative composite based on typical hospitality electrification projects.)