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We have a water heater and a gas boiler in the garage at the rear of the house.
The water heater has started to leak at one of the joints so we have decided to install a new combi boiler and get rid of the above.
A local firm came to give us a quote and told us the gas pipe to the existing boiler/water heater is not big enough (15mm) and needs replacing with 22mm.
The meter is in the front of the house and approx 30 meters from the garage (in a straight line) ,we have concrete floors and he needs to run the pipe around the rooms to get to the garage,this has added £600 to the original quote.
Is the info about the bigger diameter pipe correct ,does the additional price look fair?
Are there any boilers that will run off a 15mm gas pipe so we can get away with the upheaval this is going to cause?

Thanks in advance.

Obviously, it depends upon the size of boiler, but combi's will almost certainly require a 22mm supply pipe because they need the capacity to supply large quantities of hot water instantly.

Consider routing the supply outside your house. £600 seems a lot of money.

The original boiler was a combi and ran fine even when the gas fire in the living room was on (now coal fire) and the cooker ,when the hot water side started playing up we blanked it off and installed a water heater next to it.
Both worked fine off the 15mm gas pipe.

If we were to get a non condensing boiler (as these need more gas so the bigger pipe) would we be able to get it installed or s it now illegal?

*EDITED - Double post*

The wife has just told me the guy who gave the quote didn't look at the meter, (i assumed he had) i have just looked and it has a 22mm copper pipe coming from the meter and going under the floor.
At the garage end it comes out of the wall as a 15mm pipe and runs to the boiler approx 6 feet away,is there a chance he assumed the whole run would be 15mm because he only saw the pipe at the garage end?
We have another company visiting on Monday to give us a quote is it worth mentioning this to them or are they likely to have a look at the meter end as well as the garage end ?

The gas pipe to the boiler should be 22mm, so you will probably have to have the gas re-piped.

Also it is now a legal requirement that new installations must be a condensing boiler. There are exceptions where condensing boiler cannot be fitted or it is impracticable, for example large high rise flats where condensate discharge isn't possible.

I would imagine you would be legally required to fit a condensing boiler.

correct the gas should be 22ml from the meter to the boiler if your existing gas pipe is under concrete i would advise replacing it anyway

£600 isnt far off to be honest i would estimate 2 days work and £200 in materials copper isnt cheap you would probably need a new union

condensing boilers are law and just to say they can be fitted anywhere the legal requirement states that in high rise or tall buildings the condesing pipe and pressure releife can be directed towards the building at the outlet
regrds
andy

[quote="htg engineer"]The gas pipe to the boiler should be 22mm, so you will probably have to have the gas re-piped.

[/quote]

The pipe is 22mm at the meter end but is 15mm where it breaks through the garage wall and joins the boiler.
Ids there a way of testing the flow to see if the existing pipe is up to the job for a condensing boiler?

[quote]The gas pipe to the boiler should be 22mm, so you will probably have to have the gas re-piped.[/quote]



The pipe is 22mm but the last 2meters where it exits the garage wall and joins the boiler is 15mm.
I have been informed that if i am lucky the pipe may be 22mm all the way through the house and the last 2 meters of 15mm may not present a problem and could be changed to 28mm.
I have also been given the advice below.

[quote]Make sure that he gas rates the existing boiler (assuming that it's working) and measures the working pressure at the meter outlet and the boiler inlet, then post the figures here. If the guy doesn't know how to do this, or even why it needs doing, ditch him.[/quote]

I will keep my fingers crossed,thanks to all who have helped.

i would imagine all pressures will be correct and the guys where trying to grab a quick buck the point i was trying to get across is if you have underground gas pipes depending on how long they have been there by having them changed it will save you money in the long run if you plan on living there long term

the gas pipe has to be 22mm from meter to boiler, you wont know where it reduces to 15mm unless you want to start digging up the floor.

Sorry its taken so long to get back.

I have had another quote,this guy said he can take the new pipe through from the back of the cooker where it exits the wall (22 mm) and run it from there to the garage.
This is good news as it means not pulling up the floorboards in the living room and nor drilling through both walls of the under stairs cupboard.
The 2 prices have been similar but the first installer will be fitting a Ariston HE 30 FF combi and the second a Potterton 24 Eco HE combi,which one in your view is the better option?

Neither are great, but the Ariston is better than the Potterton

[quote="dp123"][quote]The gas pipe to the boiler should be 22mm, so you will probably have to have the gas re-piped.[/quote]



The pipe is 22mm but the last 2meters where it exits the garage wall and joins the boiler is 15mm.
I have been informed that if i am lucky the pipe may be 22mm all the way through the house and the last 2 meters of 15mm may not present a problem and could be changed to 28mm.
I have also been given the advice below.

[quote]Make sure that he gas rates the existing boiler (assuming that it's working) and measures the working pressure at the meter outlet and the boiler inlet, then post the figures here. If the guy doesn't know how to do this, or even why it needs doing, ditch him.[/quote]

I will keep my fingers crossed,thanks to all who have helped.[/quote]