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We have an old but working Baxi boiler, hot water cylinder and two tanks in the loft.
I’m lead to believe that the bore of pipe feeding the gas to the boiler is too small to support a new combi - IIRC we have a 15mm pipe and a 22mm pipe is needed.
Running a new pipe from the meter is possible but I imagine a faff as the meter is in the basement the boiler on the first floor.
Can you still get non combi boilers? Would we be foolish looking at anything other than a combi?
Curious to gauge thoughts.
There is already a 15mm pipe running the same route.
Swapping for a 22mm may not be as much a faff as you would think.
Why not get someone round who knows and ask them ? Sometimes things are a lot easier than you would think.
We had to get a 22mm pipe put in for a new non-combi boiler, they weren't sure before hand but once it was installed if the gas hob was turned on to (it ran off the same 'spur') the pressure at the bolier dropped too low.
whats your usage/bedrooms/bathroom numbers
combis not correct in every situation
- i have a combi but only have 2 hot taps coming off it.
when i looked last year non combi boilers were easy to get - non condensing was the nightmare.
I wouldn't worry about the number of taps coming off a combi, assuming you're not running a hotel and have to guarantee everyone can have their bath and shower at the same time in the morning. It really isn't a big deal in a family home to wait for one bath to fill before starting another, and the flow rate for a decent modern combi is plenty for a couple of showers or a kitchen tap while a shower is going.
The spec for the feed is less than a 1mb pressure drop to the boiler, which normally means a 22mm pipe.
Running a new pipe from the meter is possible but I imagine a faff as the meter is in the basement the boiler on the first floor.
The only faff is where the pipe goes through walls, where you'll need to widen the hole a bit. Not a huge amount of work, unless you have a very complex pipe path.
"and the flow rate for a decent modern combi is plenty for a couple of showers or a kitchen tap while a shower is going"
and there in is the nub
most new builds and many plumbers my friends have used have speced boilers to the heating requirements of the house.
consequently it takes about an hour to run a hot bath.
Maybe I've been spoiled by choosing decent boilers in the past. We did have our pump collapse a couple of weeks ago and so have been thinking of replacement since the old thing is now 13 years old. It does give us 14l/min of hot water so I guess a bath takes about seven or eight minutes to get plenty full enough. Heats 17 rads too so the replacement will have to be pretty chunky too. One of these days I'll try to do the sums to work out the gas saving if we swap to a condenser.
gas safety week this week!! lots of scary facts on the gas safe website if you take a peek..
a half decent sized new condensing combi will need the gas supply upgrading to 22mm. given the sheer distance probably 12 - 20 metres this is inevitable if your boiler is more than 22m away from the meter you may even have to go bigger dependent upon size of boiler number of bends in pipe etc.
the reason you need a bigger pipe is the volume of gas your boiler needs to burn correctly as incomplete combustion produces carbon monoxide and that is not good.. so plenty of gas needed at the boiler ( ironic as most folks install a new boiler to use less gas..)
getting gas to the thing is the least of the worries frankly.. getting rid of the condensate is normally the most hassle of getting the hot and cold water to the thing.. plus the flue position oh oh.. the list goes on..
gas safety week this week!! lots of scary facts on the gas safe website if you take a peek..
a half decent sized new condensing combi will need the gas supply upgrading to 22mm. given the sheer distance probably 12 - 20 metres this is inevitable if your boiler is more than 22m away from the meter you may even have to go bigger dependent upon size of boiler number of bends in pipe etc.
the reason you need a bigger pipe is the volume of gas your boiler needs to burn correctly as incomplete combustion produces carbon monoxide and that is not good.. so plenty of gas needed at the boiler ( ironic as most folks install a new boiler to use less gas..)
getting gas to the thing is the least of the worries frankly.. getting rid of the condensate is normally the most hassle of getting the hot and cold water to the thing.. plus the flue position oh oh.. the list goes on..