Combination boilers are a great choice for most properties with up to three bedrooms and one bathroom* and provide instantaneous hot water and rapid heating radiators, whilst keeping use of space to a minimum.

Maybe you have a home with four or more bedrooms and more than one bathroom or en-suites. In this case, you may require an unvented hot water system to cope with the added demand on the hot water that a combination boiler may not deliver.

Homes in need of renovation often have dated, inefficient or dangerous heating systems, while others may have none at all. In these cases it will be necessary to have a new boiler and radiators installed.

A central heating system consists of a heat source combined with connected heat outlets — this usually means a boiler and radiators, but it can also mean underfloor heating.

A boiler and depending on the type of boiler you opt for, a hot water cylinder and maybe a cold water tank — plus radiators and controls for the system. You can calculate how many and what size radiators you will need yourself (there are various rough calculators available online to help), or ask Mr Gas Man to do this for you. A room’s overall heating need is measured in British Thermal Units (BTU) and radiator manufacturers and suppliers will provide the BTU output for each model.

  1. Choose a boiler and select the radiators that will offer adequate heating for your home, along with new controls.
  2. Your engineer at Mr Gas Man will be able to help you come up with a plan for the system you want to install. You will also need to decide on a good spot for your new boiler and where you want to position your radiators.
  3. The radiators are usually installed first, at around four to six inches above floor level.
  4. The pipes are then laid from the radiators and valves to the boiler, after which the controls are installed.
  5. The water and the gas are shut off while the boiler is installed.
  6. All of the radiator vents will be closed, the system is filled with water and each radiator is allowed to vent through.
  7. Finally, the boiler can be switched on and the flow of heated water balanced using the valves.

Combi-boiler systems heat the water as you need it — so no need for a hot water storage tank. They also use the main water pressure so there is no need for an overflow tank.
Gravity-Fed Systems are another option which may be better to upgrade to, as opposed to replacing your system. The negatives include variable flow and the space the cylinders and expansion tank requires.
High-Pressure Systems use the main water pressure, so they usually give a lot of hot water at a good flow. They do, however, require a hot water tank