Which boiler ?
Before you begin to read through the boiler options available to you there are basics that you might as well learn now.
1. All boilers must meet Building Regulation Standards. So, whether you’re replacing an old boiler and staying with the same heating system or you’re changing from a different system, any new boiler installation requires Building Regulations approval, for both safety and energy efficiency.
This certification is generally acquired by using an accredited installer, registered under an approved scheme:
For gas boilers – Gas Safe registration
For oil-fired boilers – OFTEC registration
For solid fuel boilers – HETAS registration
If you remember this simple first requirement, hopefully you will remember to ask for your installer’s proof of accreditation before they start work – your boiler will get its certificate, you have peace of mind that the installer you’ve chosen knows what they’re doing and all’s well with the world!
Of course, if for some completely logical reason you choose to use an installer who isn’t a member of one of the approved schemes (I’m sure there must be reasons), you still have to get your boiler certified as safe and efficient which will cost both time and money.
Before any work begins you should inform your Local Authority of your intention to install a new boiler – and pay a notification fee. After the work is complete, the LA may decide to inspect the work or you can apply for a certificate to be issued after an approved scheme participant has inspected it.
2. A common question that is often asked, but rarely answered clearly is: ‘everyone I’ve had a quote from has told me my boiler has to be on an outside wall. Why can’t I keep it where it is?’
Simply put – legislation regarding boiler safety and efficiency requires all new and replacement boilers to be condensing boilers. Available for domestic installation for the past 20 years or so and far more energy efficient than non-condensing boilers, almost all gas and oil boilers installed since 2005/7 respectively have been condensing.
If you still have an older, non-condensing boiler, the length of the flue pipe needed meant that it could be installed where it was most convenient – which wasn’t always on an outside wall. The technology that drives a condensing boiler means that flues are much shorter, so need to be against an outside wall to expel the gases outside.
So – that’s why! If you insist, or there are no suitable outside walls, non-condensing boilers may still be installed in exceptional circumstances, but these are exceptional.
So – now you can begin to look at the boilers available, understand what each type is and what it does………..and make an informed choice.
Types of Gas Boilers
These are the most popular new boiler choice, forming the majority of installations over the past 5-10 years.
Small, compact and highly efficient, they heat water as and when it is needed. Heating on demand does away with the need for water tanks, storage cylinders, loft space, airing cupboards and – a real bonus in a busy house – the need to constantly plan ahead and/or hope you’re not last in the shower queue.
The only real disadvantages are that if many taps/outlets are in use at once there may be a loss of pressure; and some customers find their airing cupboard too useful to lose.
Heat Only Boilers
Heat only, or open ventilated boilers are the conventional standard type of boiler: connected to 2 tanks in the loft space and a hot water cylinder in an airing cupboard. Water is heated in advance and stored.
If you already/still have this system in place and have no real need or desire to change, this is ideal: multiple outlets can be used at once without loss of water pressure and you retain your airing cupboard.
This is a pressurised, sealed system: a sealed hot water storage cylinder in an airing cupboard. The pressure means you can run more than one outlet at a time and there is no need for an expansion tank in the loft.
It’s like a conventional system in that it stores the hot water, but as many of the components are built in to the boiler it is easier, cleaner and faster to install and more efficient to run.
For larger homes and those with more than one bathroom it is a great middle-ground option: water is still stored but the loft space is free.
A back boiler is fitted behind an open fire, heating stove or electric fire to provide domestic hot water and heating. It consists of a water-filled heat exchanger with a hot water output at the top and a cold water feed at the bottom.