Always happy to help with your central heating problems at Heatforce Wales

Frequently asked questions about our heating services, radiators and boiler fitting

A quick online guide answering a few
common questions on central heating


Paul Maddocks, the proprietor of Heatforce (Wales) Ltd, remains personally involved in the key aspects of carrying out surveys, discussing your particular needs and recommending the most effective and appropriate system.

Heatforce's aim is to provide complete satisfaction with quality products in all installations. Paul has compiled a list of frequently asked questions for your reference:

Which central heating system should I choose?

Wall mounted, floor mounted, combination or back boiler? 30,000 Btu/h, 70,000 Btu/h or 100,000 Btu/h output capacity? Open vented fully pumped, open vented gravity or fully pumped sealed system? How do you decide which central heating and hot water system is best suited to meet the needs of your lifestyle and your property?

My heating hasn't let me down yet, so should I change anything?

Much progress has been made in the development of central heating. Boilers have become more efficient, controls more accurate and system design has benefited considerably from this. So whilst your heating may still be working fine on the surface an upgrade to a more fuel efficient system may lead to a significant saving on your fuel bills. Not only that, but controllers are far more sophisticated these days which will enable you to control your system to match your lifestyle and again can lead to fuel savings.

So now I have my new central heating system, that's it then?

No, your new boiler and system should be safely and properly looked after as this will maintain its performance and your safety. We offer annual servicing for your boiler, gas safety checks and can assist with repairs and breakdowns.

Why won't my combination boiler supply hot water to more than one tap at a time?

This is because all combination boilers have to warm the water up from cold as it is running and this takes a lot of energy, this is limited to gas supply so all manufactures limit the boilers to about 30KW and this is just enough to lift the water temperature up to 60 deg C if water flow is about 1.5 Gall/min.

Are combi boilers only used on sealed systems?

Combination boilers are designed to be used on sealed systems that is they have an expansion vessel built in. But if fitting one onto a system with old radiators then it is sometimes advisable to fit an expansion tank so the extra pressure can not damage the radiators or valves.

Why do my radiators keep bursting?

The most common reason is corrosion in the system, this can be caused by the system not being flushed out correctly when new or being wrongly installed, but it takes quite a few years for the first radiator to leak. the system needs checking over, if any design fault is found it needs rectifying then flushing out and inhibitor added.

My plumber claims that my combination boiler doesn't need a room stat?

Technically they are, correct providing every radiator has a TRV fitted and a by-pass is incorporated but this will increases the stress on the boiler, increasing running costs and reducing your boiler's lifespan. The best systems have a room stat fitted near the main living area and only have TRV's fitted in bedrooms and south facing rooms, this will allow the boiler to rest when the house is warm, reducing wear and tear and the cost of your fuel bills. The best control for combination boilers is a programmable room thermostat then no other time clock is needed.

My shower keeps running hot then cold then hot again.. is it fitted to a Combi?

Usually this refers to the how the gas burner operates. Some boilers are fully modulating which means the gas pressure is controlled electronically keeping the output constant, other boilers are semi modulating which usually means the boiler has a full rate and a low rate and alternates between the two. A semi modulating combination boiler would result in a non thermostatic shower varying in temperature. If you have poor water pressure or something else is drawing water at the same time, like a flushing toilet or washing machine for example, this could also cause a shower to run cold.

One of my radiators is cold?

When you bleed the radiator did water come out? If not and if you have a sealed system is the pressure gauge at 1 Bar? Try turning the radiator valve fully open (anticlockwise) and on the opposite side there should be a cap that you can't turn, remove this cap and using a small spanner make sure that the valve spindle is fully open (anticlockwise). If there's still no heat try turning all the remaining radiators off and then put the heating on only.

What next?

Call today For more information on our boiler finance, bathrooms, fireplaces, heating services and renewables or if you are interested in having a free site survey to discuss your requirements

Call us on 02920 763622

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or visit one of the Heatforce fireplace & bathroom showrooms in Cardiff, Caerphilly & Merthyr Tydfil.

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