Knowing hot and cold

Climate control is about more than just maintaining a cool office in summertime – the best systems keep the workforce and the management content all year round

by Rob Tysoe

06 April 2007

Air conditioning is about more than just keeping your office cool in summer and warm in winter. A comprehensive climate control system should ensure that the heating and cooling requirements of a building and its occupants are met all year round, without unnecessary strain placed on the environment. It is important to ensure that any systems for controlling an internal climate are installed with the capability to provide a consistent temperature throughout the year, regardless of external temperatures.
The best type of system will allow for simultaneous heating and cooling within specific areas of the same building, if required. In order to select the right system, attention should be given to certain key areas.

1  Use the right people

When selecting an installer, be sure to seek out a reputable company with industry accreditation. Established companies such as Daikin, Mitsubishi, Sanyo and Toshiba have preferred installer schemes, where qualified personnel are involved in the design, installation and commissioning process throughout. Check the installers and engineers hold relevant qualifications – NVQs, City and Guilds qualifications and Refrigerant Safe Handling certification. The Heating and Ventilation Contractors Association (HVCA) conducts a detailed assessment of firms’ standards of competency prior to offering or approving membership. Look at previous contracts undertaken by a company to ascertain the standards of workmanship.

2  Hot and cold

As mentioned previously, most modern systems offer heating as well as cooling. In recent years, the UK has seen a shift in energy-consumption patterns from a winter peak to a summer peak. This is a clear indicator of climate change affecting the ways in which building temperatures are regulated. Current inverter driven equipment produces energy and cost efficient cooling/heating systems, and offers high COPs (coefficient of performance).

These types of systems are also significantly less disruptive to install, and are able to react to match the environmental demands of the building, speeding up or slowing down as required, preventing large power surges and reducing carbon emissions. In terms of the air conditioning in a particular building, the things that must be taken into account are the normal temperatures of the air outside and the air inside, and how quickly and efficiently that air that will be supplied and circulated throughout. Thermodynamics is a tricky thing to get right. For example, if the speed of air flow through a building is high, the air temperature should be raised accordingly. Similarly, workers in largely sedentary roles should be subject to higher temperatures than those in positions involving large amounts of manual labour. Factors such as these, as well as differing levels of comfortable working temperatures between individual workers, mean that ensuring thermal comfort for everyone is a difficult but essential task.

3  Be in control

For optimum effectiveness of operation, a system with the appropriate control system should be specified. Smaller split systems, either infra-red or wall mounted have 24/7 control. For entire office blocks, larger systems such as VRV and VRF use a building management system (BMS), which interacts with other buildings services equipment such as fans, pumps and lights. This again enables the building to operate with a degree of efficiency that can reduce needless energy usage.

4  Maintenance

Energy efficiency is likely to become the main driving issue behind building design, and particularly, the specifications of air conditioning systems. Improvements in design are always being made and the efficiency of systems is constantly on the increase. Despite this, the use of systems in workplace buildings is still rising each year. As the climate continues to change in response to emissions from buildings and transport, the use of air conditioning in the workplace will continue to adapt and, more than likely, increase.

With this in mind, it’s important that your system is well installed, well maintained and will run efficiently. Due to their complex nature, air conditioning and refrigeration systems must undergo planned periodical maintenance inspections, in order to pre-emptively prevent problems or unnecessary system breakdowns. This is the simplest way to avoid risk and inconvenience to an organisation, its staff and its premises.

Rob Tysoe is divisional manager of breatheair

Consider the impact on the environment

Cost effectiveness should not be the only consideration when selecting a system. Its impact on the environment should also be a factor. Refer to the government’s ECA ‘Technologies List’ of environmental products that are subject to tax relief (Enhanced Capital Allowance), offering up to 100 per cent relief in the first year of purchase in some cases (The list can be viewed at www.eca.gov.uk)

Any cooling system selected should always contain R410a ozone-friendly refrigerant and have a good energy rating. Levels of energy consumption are currently changing at a staggering rate. Some estimates predict a 100 per cent rise from current consumption levels for commercial premises by 2020. In a typical office, air conditioning can account for up to 30 per cent of annual electricity consumption – representing almost as big an impact on an organisation’s finances as on the environment.