Anyone who saw my indignant rantings on Twitter yesterday will know that 2024 started off for me with a broken down boiler and plumbing rip offs..er….sorry …plumbing quotes. I returned from the xmas break away to no heating or hot water. Great. The problem was compounded by being in holiday season which meant suffering several days of ‘camping indoors’ before I could get it fixed
So, today I’m sharing some basic knowledge about boilers and installations so you don’t get ripped off by plumbers if it happens to you. Forewarned and all that….
Boiler Sizing Requirements
“Combi” boilers come in four sizes 24-25kw , 28-30kw, 33-35kw and 40kw. Flats and small 2-3 bed homes will only need a 24-25kw, which will heat up to 10 radiators. The 28-30 covers a medium to large 3-4 bed house with about 15 radiators. 33-35 and a 40 kw are for large houses with 20 radiators. The more hot water you use, via extra bathrooms etc, the higher demand or kw (kilowatt) boiler is needed. No instant combi boiler can cope with 2 showers running at the same time. Fact.
Where You Put It Impacts Price
Putting the new boiler in the same location as the existing always reduces cost. Less copper pipe = less money. Replacing an existing combi with another combi means all the required pipes will be already be there. Converting from a tank system to a combi requires 2 additional pipes, hence more cost. You will also need a condensing drain pipe outside. The closer to an outside wall it is sited, the cheaper it will be, because the flue ( which takes away gases) needs an exit, and flue pipe is not cheap. ( A straight extension piece for example costs over £1o0.) Asking the plumber to use plastic not copper for underfloor pipes can save at least £200 off an average quote.
Boilers can live quite happily outside the house so long as the pipes are lagged and it’s in an outhouse that is fireproof and watertight. Ideally, in a brick or block shed. We have sited them in old outside loo sheds and they work just fine, plus you have the advantage of not wasting valuable wall space inside kitchens or bathrooms.
Boiler Makes
Most plumbers have their favourite boilers that they prefer to fit. The Rolls Royce of boilers are Vailants & Worcester. Baxi or some Ideal tend to be cheaper but are also considered good, though plumbers seem to think Ideal break down more often. The main difference is the warranty provided and personal choice. A little known fact is that some boilers are renamed but have the same innards as more expensive ones. Some Glow Worm boilers are actually Valiants in disguise, for example, and around £200 cheaper.
Gas Pipes & Controls Are Important
Pipes going in to the combi boiler should always be be 22mm diameter. Boilers fitted with thinner pipe will cause malfunctions and make the boiler burn more gas for less heat output, and thus, will be more expensive to run. You will need a room stat, the cheapest option is a wireless one. Thermostatic radiator valves are a ‘recommended addition’ not essential, and are definitely not a legal requirement. They can push the bill up considerably at £10-15 + VAT for each radiator. Combi boilers need good water pressure which should be tested before any quote is given.
System Flushing
It is possible that your warranty could be void ( though this is a grey area) if your new boiler becomes damaged because of sludge from your existing system. However, most plumbers who do a good job will flush the system when fitting new boilers as a standard practice. You do NOT need a power flush. These are only needed when the system is already very sludgy, and again, will cost considerably to have done.
Man Hours Involved
A straight forward exchange is about 6-10 hours – or 1 day for 1 man. A conversion from a system (tank) boiler to combi can take up to 3 days, depending on how much piping and radiators are fitted and the overall job complexity. Usually done by 2 plumbers.
Boiler quotes can vary wildly. I’ve had quotes from £1800 to £3000 for the same job. A straight exchange should cost between £1400 – £1800 (inc vat) depending on size and type of boiler. A conversion will be between £1900 and £2500, presuming you are not adding radiators and extras such as mentioned above. You can bank on radiators costing about £100-£150 each for standard sizes.
Finally, putting morals about tax aside, I have never met a plumber yet who will not do a cash job by knocking off the VAT, saving you a further 20% of the overall cost. Don’t let a few days of discomfort force you into rash buying decisions. The key to saving money is to research before committing. Oh! One last tip, plumbers love to include “taking away waste” in a quote because copper pipe, old radiators and cylinders fetch great money at recycling centers. Taking the Copper pipes etc to metal recycling can recoup at least £100 in lovely cash
You may also be interested in our Save Money Around The Home article which has more money saving energy tips.
Janet Trowell Discountletting.co.uk Join me on Twitter LinkedIn Google plus
By editor|January 3rd, 2024|Categories: Health & Safety Issues, Mentor Moments, Property Development|Tags: boiler, central heating, combi boiler, Fitting, heating, money, new, save, warranty|3 Comments
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Plumbers generally are one of the biggest home expenses and charge ridiculous fees for the work done, and, as I said, vary wildly for the same job with the same fittings.
We have fitted plastic piping before and never had an issue with it. All fittings can cause issue, even copper. Copper joints can split especially in cold weather.
I don’t believe that ‘you get what you pay for’ as regards to gas engineers. If they cost 30-40% more as fitters, and often charge more for the same boiler to make a fast buck, then you are not saving anything.
Plumbers already make 30% on wholesale cost of the boiler/fittings so adding more is just a rip off to the customer.
Lastly, if a boiler can last 15 years then the manufacturers should offer a 15 yr guarantee and plumbers the same for their work. Now that would be fair.