Frequently Asked Questions

Here are a selection of questions we get asked by our clients. We hope you find the information useful, but if you don't find what you're looking for here then please don't hesitate to get in touch.

Call 020 8914 8316 or e-mail send us an enquiry to book your engineer today!

What sort of boiler do I have at the moment?

To tell a condensing boiler from a non-condensing boiler, look at the flue that sticks out from the outdoor wall adjacent to your boiler - and the type of waste heat it lets out into the atmosphere.

A flue is a pipe that takes the exhaust gases generated by your boiler and passes them out through the wall or roof - letting them escape into the air. The end of the flue is covered by a metal or plastic protective cover, which makes sure that a good flow of air is maintained.

If the flue is made of plastic and lets out visible steam when the boiler is firing, then you are likely to have a condensing boiler already.

If the flue is made of metal and no steam is visible, you are likely to have a non-condensing boiler. These older boilers let out much hotter gases that are invisible to the naked eye - and would melt a plastic flue.

I want to replace my old boiler. How do I know what size of new boiler to get?

The type and size of your new boiler will depend on a range of factors like the size of your property, how many bathrooms you have and the type of fuel and heating system you currently use to heat your home. Please do not hesitate to call us for free advice.

Is a combi boiler more efficient than a regular condensing boiler?

A combi boiler can be more efficient because of the way it supplies hot water to your home. Other types of boilers produce hot water and then store it in a cylinder for use as and when. This is quite an efficient process - but if the hot water is not used immediately, then inevitably some heat will be wasted.

How often should I get my boiler serviced?

It's important to have your boiler serviced once a year. The flue will need checking to make sure it is clear, and we can also check that your boiler is running safely and efficiently for you.

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Based in West London, S1 Heating Installs offer a complete range of plumbing, heating and gas services including
Combi Boiler Installation, Boiler Installation, Gas Boiler Service & Repair, Power Flushing, Landlords Gas Safety Certificates, Solar Hot Water  

We operate throughout London and the South East, especially in:
Acton W3, Chiswick W4, Ealing W5, Hanwell W7, Shepherds Bush W12, West Ealing W13, Paddington W2, 
Maida Vale W9, North Kensington W10, Notting Hill W11