Next you will need to ensure that your gas supply is large enough. Existing gas regulations insist that the working gas pressure at the boiler does not fall by more than 1mbar, compared to that at the meter whilst in use. This normally requires at least a 22mm copper pipe to be installed from the meter to the boiler.

Next you will need to install or alter the existing hot/cold water pipework  (if you are fitting a combination boiler). This can be straight forward if you already have a combination boiler, as the pipes are already there, but if you are changing from a conventional boiler then new pipework is needed and this will be more expensive. If you are moving a boiler or starting from scratch then this will add to the cost. 

The main Flow/ Return pipework for the boiler will need to be installed or altered, this can be simple or complicated depending on the type of boiler and whether or not you already have the pipework installed. Some boilers we come across have incorrectly sized pipework and this will need to be upgraded, otherwise you may experience flow problems. Condensing boilers also work more efficiently if the return temps are kept low, this can be achieved by having the correct size pipes. If you are installing a brand new system then this will cost more .

Next you will need a condensate discharge system to carry away the water produced when the boiler is operating. The pipe needs to connect to either a existing waste pipe or a gulley trap. Sometimes if there is not a suitable drain point , a soakaway can be installed. Difficult situations may require a pump to be installed. .

Next you need to flush the system to ensure it is clean and no harmful sludge/particles are present, some systems can be very dirty and full of sludge, the water resembling thick mud. If this is the case a full powerflush will be needed, otherwise this will enter the new boiler and block up the heat exchanger, thereby invalidating the warranty. The water quality varies from boiler to boiler, some we remove are very clean and only require a manual flush, followed by a inhibitor to protect the system.

Next you will need to look at the controls that are required, programmers, room thermostats, cylinder thermostats, wiring centers, zone valves etc. A combination boiler will only need a timer and room thermostat, which can be wired or wireless. If you have a conventional boiler then you may need to upgrade the controls, which will include either a 3 way valve or 2 x 2 way valves, a cylinder thermostat, room thermostat, programmer, pump, wiring.

We strongly recommend the fitment of a Filter on the return pipework to the boiler, as the new condensing boilers these days have very narrow waterways in the main heat exchanger and get blocked very easily, which will reduce efficiency and eventually prevent the boiler from working (you have been warned !)

You may also consider the fitment of a scale inhibitor if you have a combi boiler and live in a hard water area.

To sum up the cost of installing a new boiler can vary and be dependent on a number of different factors, every install is different and we have listed on our main page some prices for combination boilers (supplied and fitted), if you have a conventional boiler or any other type of boiler system , we would be happy to discuss it with you and arrange for a site survey to provide a quote.