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BPECCity & GuildsW.R.A.SPart P Electricalgas safe register

Gas Safe Registered Business

Reg No 187647



Every year you should get your gas central heating boiler checked by a Gas approved installer
to keep the boiler working safely.

If the boiler is not maintained at all then this could lead to the boiler not functioning correctly and the danger of carbon monoxide poisoning (the silent killer) .

Always use a Gas approved installer then you know your in safe hands, never D.I.Y with gas .


Give Andrew Dodsworth plumbing & Heating a call if you would like an estimate on the following.

New condensing gas boilers.
Un-vented hot water cylinders installed, Commissioned and serviced
Central heating design and installation.

Radiators moving or replacing.

Thermostatic radiator valves installing.

Underfloor heating installations

Heating systems Power flushing and cleaning.

Boilers repaired or servicing.

We are City & Guilds qualified in energy & efficiency for domestic heating systems.


One fact that all experts agree on and has been repeated time and time again is that it is always beneficial from an energy saving point of view to fit a condensing boiler.

Condensing boilers are the most energy efficient Central Heating boilers on the market today. They achieve this high level of efficiency by removing the heat from the fuel it is burning and also cooling the products of combustion, which are normally wasted up the flue, so much so that the water vapour in them turns into liquid. This happens at around 58°C. For a boiler to cool the flue products this much, it has to have a larger, more efficient heat exchanger than traditional boilers.

To make the system more economical to run and use less gas we have now to fit thermostatic radiator valves to all the radiators except the radiator located in the same room as the wall thermostat (best practise)..

All new boilers need to have "boiler interlock" this means a timer and a thermostat to control the boiler or a programmable room thermostat e.g. to turn off the heating system when the house has reached its desired temperature.

To install a new condensing boiler to an existing heating system would mean fitting the new boiler, power flushing the entire central heating system (if this is not done then in most cases the manufacturers guarantee would be void).

Installing new thermostatic radiator valves to all but one of the radiators, fitting a new room thermostat and timer unit (if not incorporated in the boiler).

Fitting a new hot water cylinder if the old cylinder is not pre-lagged. Fitting a thermostat on the new cylinder and making the water feeds to the cylinder fully pumped if the existing system is a gravity system.

If the boiler is to be fitted to an existing system then we would always recommend fitting a magnetic filter in the return pipe to the boiler to protect the boiler further (as most repairs that we do is because the boiler is full of magnetite or rust from the old radiators and this would lead to big expensive problems with the boiler in later years)

We then fill out the log book for the boiler and register the boiler with building control on your behalf and with the gas registration scheme providers.

We install Baxi boilers as we think they are one of the best on the market with a good after sales backup if any problems arise and one of the top boilers in the Which report.

Check out the Baxi website by clicking the link below.

Baxi Boilers

Useful notes

Faulty Radiators

If a central heating system has been fitted correctly, Flushed out and inhibitor added at installation and topped up if the system has been drained down then the radiators should never go faulty.
A radiator has no working parts but the water within the radiator can damage (rust) the steel radiator if the water is corrosive.

If you have got damage to the radiators then often the first sign is when a radiator leaks, Cold spots coursed by a sludge build up or constantly having to bleed the radiators. If you have bleed the radiators and the water is Black then you have a slight problem but if the water is Brown or Orange then you have a major problem and it needs sorting out before it gets to the stage of a different radiator starting to leaking every few months.

For Power flushing we are found to be cheaper than the big well known heating service companys and do the same job using the latest power flushing unit with the one of the best chemical descaling fluids on the market.

All power-flushes are fully guaranteed,

Please check out our power-flushing web site for more information


(The diagram below shows what happens to the heating system when there is a build up of sludge)

heating system problems


Flueing & Ventilation

All gas burning appliances need air to burn and to be able to get rid of the burnt gas out of the flue, Most modern boilers are called room sealed (fan flued) which means all the air for combustion of the gas is taken from outside through a duct and the fumes from

the burnt gas is taken through a second duct back to outside (usually the flue duct is inside air duct).

There are a lot of older boilers still in good service out there which are open flued these take the air for combustion from an air grill fitted in the room in which the boiler is located , then the fumes go up the flue which terminates above the roof.
If for any reason the flue gets damaged or the ventilation grill gets blocked or even if a fault develops within the boiler itself then poisonous fumes could enter the living space.
Most boilers now are fanned flue and room sealed which is the best and the safest option.

Most boilers also need extra air to keep them cool especially if fitted in a compartment,
although most modern boilers do not need any extra air for cooling..
The size and position of ventilation depends on the heat input of the boiler, the type of flue and where the air is coming from

There are a lot of regulations for safety of the flue and ventilation and if you are in any doubt then consult a gas registered installer to check, but as all gas appliances should checked for safety once a year then any faults or potential faults should be picked up then.

© 2009 Andrew Dodsworth Plumbing & Heating. All rights reserved.