Converting over to a combination boiler from an open vented boiler involves quite a lot of work.
With a combination boiler you don't need any form of water storage tanks at all, the hot water and cold water storage tanks, along with the feed and expansion tank for the central heating can be removed.
If there are any pumps fitted to boost your water pressure to your shower or other taps within your property, then these have to be removed, as you cannot pump water with a combination boiler.
One thing that people don't realise is, when you have a combination boiler fitted it works under high pressure and the boiler that it replaces is normally low pressure.
This could cause leaks on the pipe work, even the radiators.
It may have been OK beforehand working on low pressure, but it has not been tested working under high pressure.
It doesn't always happen but it's something that has to be considered when converting over to a combination boiler.
If your old boiler is high pressure then all should be OK.
When converting over to a combination boiler you have to make sure the incoming water mains pressure is good enough.
I have seen combination boilers that are just about working due to low water pressure.
You need to have at least 1.5 bar incoming water pressure if not more.
You can now get mains water pressure pumps to boost the incoming water supply, but they will only boost the incoming water up to 12 litres per Minute and they are very expensive to buy.
The gas supply needs to be checked when converting over to a combination boiler, most boilers these days need a 22 m gas supply and not 15 m as you find on most older style boilers.
Though the modern day condensing combination boiler uses less gas, they work in a completely different way to the old style boilers.
Condensing boilers suck the gas they need whereas the old boiler just let the gas in when required.
If you are thinking about converting over to a combination boiler you have to make sure you get the right model for your property.
If you have more than two bathrooms that will both used at the same time, then a combination boiler is not really a good idea, as with most combination boilers you can only use one hot tap at a time.
There are some models on the market that will let you use more than one tap but they are still very expensive. Some even have a small hot water storage tank fitted internally.
With the hot water now working under high pressure you have to check all your hot taps for leakage or dripping, because before they were working under low pressure.
The same goes for the cold water taps in the bathrooms and toilets.
If you have the cold water storage tank removed and the cold supplies converted to mains pressure then again you need to check for leakage on taps for dripping.
The toilet is normally the first problem you will come across, water may be running out of the overflow pipe or continuous running in the pan, as most ball-valves are fitted with a low pressure valve and will need to be converted to high pressure.
Converting to a combination boiler is a good idea if want to save Money on your fuel bills, because with the hot water you are only paying for what you use,
whereas with the old hot water storage tank you paid for a full tank of hot water, but if you don't use it all, then over time it will start to lose heat and the boiler will then come on to reheat it, costing you money.
Converting to a combination boiler has many advantages and disadvantages.
If you are considering converting over to a combination boiler then it's a good idea to contact a local gas safe registered engineer or company who can advise you on your needs.
You can find your local gas safe engineer on the gas safe register. Just type in your post code and you will be given three local engineers to make contact with.
If you are interested in converting to a combination boiler and would like some more information, enter your details in the box below and request a callback....
Time was taken to talk us through the work before we had it done so we knew exactly what to expect, was also very flexible with some extras we decided on last minute. Overall, very happy with the work that was carried out at what we feel was a very reasonable price. Would recommend and would use again.
Excellent work. Wouldn't have known he'd been in apart from having a new boiler! Very reliable, came just when he said he would. Made an extra effort to source the boiler and fit it in the shortest possible time so I wasn't left without heat and hot water for very long. I would highly recommend.