Thinking outside the boiler
When specifying heating systems, housebuilders must take a lot into account to ensure they maximise the efficiency returns. Sean O’Dwyer, applications design manager with Potterton, offers some advice on best practice
THE integration of an appropriate heating system into a new build is vital to maximising the level of heat output and efficiency for the homeowner. Equipment selection and system design are the first steps to achieving a high performance, efficient heating system.
When planning a heating system, the housebuilder will usually have engaged the services of a Standard Assessment Procedure (SAP) assessor. The assessor would have made recommendations on heating systems in order to reach the client’s required rating.
As well as achieving an appropriate SAP rating, the heating and hot water systems need to perform well in the real world.
Potterton's Newdesign team provides a complete design service for residential developments. We work with SAP assessors and other technical parties to help housebuilders to meet carbon and/or energy targets. We will review and adjust heating and plumbing design plans, as necessary, based on customer feedback, to ensure that the final system is the most suitable for the property.
Although 80% of our customers usually have an idea of where the boiler or cylinder needs to be sited, this can change depending on whether the placement of these systems will be detrimental to the heating or plumbing design.
The usual position for boilers is in the kitchen or the utility room, and for cylinders it is normally airing cupboards. However, recently, as customers want more space, boilers have been moving out of the kitchen and into garages, airing cupboards, lofts and W/Cs.
Radiators should ideally be placed beneath window sills, where possible, as cold air entering the room is heated by the convective air.
If radiators are placed away from windows then cold air is drawn across the room to the radiators, creating a draft. The size of the room needs to be considered when allocating wall space for radiators. The heating reach is usually 2.5 metres from the radiator and therefore if seating areas are situated outside of this range cold spots maybe experienced by the occupants.
The flue position is critical, as boundary lines must be followed whilst still being aware of window openings and nuisance from pluming. Installers should consult the boiler manual for guidance on positioning the flue to maintain the minimum clearances and prevent any issues arising in the future.
All heating systems should be designed and installed in compliance with Building Regulations, which give guidance on the minimum level of heating system controls required. Under the regulations, a property is required to be split into a heating zone for every 150m2 of floor space with an interlocked thermostat to control each zone
As well as selecting the correct thermostat for the system, the location of the thermostat has a major effect on comfort levels and efficiency of the system.
While there is no perfect location to suit every property there are some pitfalls that should be avoided. These include installing thermostats in rooms that have another heat source; installing thermostats in small enclosed rooms; and fixing the thermostat on the adjoining walls of a cylinder cupboard, as this will affect the temperature reading.
There are some key commissioning procedures to ensure trouble-free operation.
Once the system has been installed it needs to be flushed so that any debris from the installation process can be cleaned out of the system.
The system should then be filled with the correct quantities of the relevant water treatment solution. This can all be performed before the boiler is fitted to the system, therefore protecting it from all the debris and allowing it to be fitted straight into a clean system.
For new build properties this also prevents boiler theft as the boiler doesn’t need to be installed until the property has been sold.
Failure to clean the system and treat it with the correct chemicals can lead to system failure, as sludge and debris will cause the heat exchanger to fail and reduce efficiency whilst causing corrosion to the heating system.
A full commissioning process must take place once the heating system has been installed. This is an essential part of the process as it enables the system to function correctly and provides a record for future checks to maintain system efficiency.
By installing the right system for the property and placing equipment in the correct location in the home, homeowners' heating and hot water demands can be sufficiently met. This ensures that the chosen heating system will provide comfort, trouble-free operation and efficiency.
Sean O’Dwyer is application design manager for Potterton