New heat pump air curtain passes BSRIA tests
with flying colours and gains ET listing
An innovative new heat pump-based air curtain has passed independent tests by the Building Services Research and Information Association (BSRIA) with flying colours, and been accepted onto the Government-backed Energy Technology List.
It was developed by Fred Shaw & Co Ltd in conjunction with engineers from Toshiba Air Conditioning UK specifically to meet the requirements of the UK market.
Unlike conventional electrically-powered air curtains, the new air curtain connects to a high performance VRF or multi-split system, enabling it to deliver outstanding efficiency and providing additional capabilities.
BSRIA researchers analyse data from the testing process
The new system which is designed for mounting over entry doors in shops, hotels and offices, was designed to significantly cut end users’ energy costs, and to be exceptionally easy to install and service.
It was subjected to a battery of live tests at BSRIA’s laboratories in Bracknell, to evaluate its thermal efficiency, acoustic and air-flow performance under internationally-recognised test conditions.
Thermal performance tests were carried out in BSRIA’s specialist twin chamber using the calorimeter method, in accordance with BS EN 14511:2013. This enabled heating capacity and Coefficient of Performance (COP) to be determined.
Schematic showing airflow distribution
Airflow tests were carried out in accordance with BS ISO 27327-1:2009 to determine free air airflow rate, uniformity of air outlet velocity, and air outlet velocity projection.
The test rig for the free air airflow rate test was purpose-built by BSRIA to meet the requirements of the standard and the specific dimensions of the air curtain. For the air outlet velocity uniformity and projection tests the air outlet velocity was measured at 125 locations.
coustic tests were carried out in accordance with BS EN ISO 3741:2010 to determine the air curtain’s sound power level. Testing was carried out in BSRIA’s 210sq m reverberation chamber thermal-acoustic facility.
The results showed the air curtain’s air outlet velocity uniformity was 91per cent, against a target of 85per cent. The acoustic test results showed sound pressure to be 54dB(A), while the COP was determined to be 3.0.
The results proved the technology meets the performance requirements of the UK Energy Technology List for air curtains, and it has been accepted onto the scheme. This gives end users a tax advantage on capital used to purchase ETL-listed equipment, which qualify for Enhanced Capital Allowances (ECAs) under the programme.
A BSRIA technician sets up the metering system for the air flow tests on the new Toshiba air curtain
The air curtain is available in two chassis lengths, 2200mm and 1500mm, both suitable for surface or recessed installation. Surface mounted units have an optional mounting flange accessory enabling use with ceiling tiles.
There is an optional electric back-up heater, which automatically switches in during heat pump defrosts. The heat pump-driven system gives the air curtain additional optional capabilities, says Toshiba, which users can specify to augment the air curtain’s functionality.
Ease of installation and servicing was a key design principle. The unit has a hinged front panel to give engineers full access to the coil, drain tray, filter and electrics. This can be opened by one person for servicing, while other air curtains require the whole front panel to be removed, requiring two people for safe working.
For enhanced energy efficiency and performance, the air curtain uses EC motors with full 0-10V speed control, enabling air speed to be precisely matched to the unit’s mounting height. Precise control of motor speed also gives low operational noise.
Other innovative features include a filter clean warning light, and defrost on, power on and operation on lights as service aids. The PCB can be easily accessed via a sliding back-plate. The unit can be powder-coated to any RAL code to match interior decor or branding colour-way requirements.
Gary Tingle, director at Fred Shaw & Co Ltd, said: “Air curtain technology has not moved on for decades. Conventional electrically-powered systems can be costly to run, and difficult and expensive to maintain.
“Working with Toshiba Air Conditioning UK, we have taken a fresh look at this whole area and believe a heat pump-based system, harnessing the inherent thermodynamic efficiencies of VRF and multi-split systems, represents a huge leap forward. It will save end users on their energy bills, offer quieter running, and be easier and cheaper to install and service.”
He added: “End users not only benefit from lower running costs over the lifetime of the equipment, with the ETL listing they can claim Enhanced Capital Allowance on the initial purchase, too. We believe that with this new design, the air curtain has come of age, and that it offers a compelling alternative to outdated traditional air curtain technology.”
Madison restaurant at St. Paul’s in London has installed the new heat pump air curtain over the main door
The first venue in the UK to install the new air curtain is Madison restaurant at St Paul’s, London. The restaurant, renowned for its buzzing atmosphere and spectacular city views, wanted to deliver a high-quality indoor environment for customers, while ensuring low energy and servicing costs.
Installed above the main front door, the air curtain provides a high velocity continuous down-draft of air, creating an invisible barrier that maintains internal comfort conditions for customers and staff.
It is connected to the restaurant’s Toshiba SMMS-e VRF air conditioning system, enabling it to benefit from its high performance, low energy operation.