Recently published updates to Part L of Building Regulations will enforce tighter water heater energy efficiency standards from June 2022. Energy managers should start planning now for the changes ahead, says Rob Erwood, Specification and Sales Director at Baxi Commercial Solutions
On 15 December 2021, the government published updates to Approved Document L of Building Regulations relating to the conservation of fuel and power in existing non-domestic buildings. One of the changes relates to stricter thermal efficiencies for domestic hot water systems.
From 15 June 2022, direct-fired water heaters must achieve a minimum heat generator seasonal efficiency of 91% (GCV) for natural gas and 92% (GCV) for liquefied petroleum gas (LPG).For indirect-fired water heaters, the minimum heat generator seasonal efficiency is set at a minimum seasonal efficiency of 91% (GCV) for both natural gas and LPG. The tighter standards apply to both existing and new non-domestic building stock.
The uplift is part of the government’s roadmap to help the UK move towards its net zero target by 2050 and represents an important step towards more energy-efficient existing non-domestic buildings.
Given that hot water is a critical service, what will these changes mean for organisations?
Many buildings, including hospitals and leisure centres, rely on direct-fired water heaters to provide an efficient means of delivering large volumes of sanitary hot water in a short time. And currently, many still rely on non-condensing water heaters.
At present, there is the opportunity to carry out ‘like-for-like’ non-condensing water heater replacements when the existing equipment comes to the end of its serviceable life. The advantage of this ‘easy fit’ approach is that, as no major work is involved, the appliances can be replaced quickly with minimal disruption to the daily operation of the building.
But this option will soon disappear for the vast majority of cases. For this reason, we would encourage energy managers to plan ahead now to future proof their hot water system.
20% more efficient
First, let’s consider the benefits to be gained from the government’s move to rule out non-condensing water heater replacement in existing buildings. Condensing water heaters are up to 20% more efficient than non-condensing models. Models like the Andrews Water Heaters ECOflo and MAXXflo EVO, for example can achieve near maximum gross efficiencies of up of 98%.
Switching to more energy-efficient condensing water heaters will help organisations make vital progress towards achieving their environmental commitments. When managing more than one site, it follows that the greater the buildings’ demand for hot water, the greater the energy, carbon and cost savings from the upgrade.
The shift to condensing technology also encourages a reassessment of the building’s hot water requirements. Many organisations will have experienced changes in building occupancy and energy usage in the last two years or so. Ultimately, the revised calculations could point to a smaller water heater now being required, which would reduce both initial capital expenditure and longer-term running costs.
Plan ahead
But here’s the caveat. While the move from non-condensing to condensing water heaters can and should be relatively straightforward, certain factors, such as flueing and condensate arrangements, may require advance consideration.
By planning now to future proof their hot water systems, energy managers can protect their businesses and organisations and avoid the risk of costly and extended downtime.
Government guidance states that in very exceptional circumstances, where condensing water heater replacement is deemed not suitable or practical by the Building Control Body, a minimum seasonal efficiency of 80% for gas, or 79% for LPG may be used. However, even on the few and far between projects where exemptions may apply, forward planning is essential to avoid any risk of censorship from the Building Control Body.
So where to start? One of the simplest approaches is to implement a robust asset management programme. By conducting regular condition surveys and inspection of plant room assets, energy managers will be able to prepare for future change, schedule future upgrades and replacements, and budget ahead. Not only will this simplify the replacement process, but it will ultimately help protect the company coffers.
What’s more, with a proactive asset management programme in place, planning the company pathway to improved sustainability will also be easier.
In many older buildings, the decarbonisation challenge may seem huge. But taking a phased approach to refurbishment is an achievable means of meeting longer-term goals. Upgrading from non-condensing to highly efficient condensing water heaters – a key remaining ‘low hanging fruit’ option – is a significant first step that will help bring the building up to code.
A natural progression, budgets permitting, would be to integrate low carbon air source heat pumps with condensing water heaters in a hybrid system to achieve a greater reduction in the carbon footprint.
Don’t get caught out
At the end of the day, no organisation wants its building to be left with no hot water supply. And with the new minimum efficiencies set to be enforced in just three months, the clock is ticking. That’s why we would urge energy managers to proactively start future proofing the hot water system.
At Baxi Commercial Solutions, we look forward to supporting organisations with site visits, sizing calculations and help in ‘triaging’ the hot water system, so that the most appropriate hot water solutions and routes to increased sustainability can be achieved.
Andrews Water Heaters is part of Baxi Commercial Solutions.