Need a new boiler - want a combi boiler, but is a system boiler a better idea for us?

blizeH

Hi,


We need to replace our old Ideal Classic boiler as it's kettling on an almost daily basis. We have a 4 bed house with 2 bathrooms, though just 1 shower is ever used at a time.

I'd like a combi boiler because:

• It'd let us remove the water tank in the airing cupboard, and all of the stuff in the loft.
• It'd greatly improve our water pressure, which is very poor at the moment
• I'm guessing it's much more efficient to only heat the water we use

However:

• We've just replaced the heating pump to try to fix the kettling issues
• We have a Solar iBoost for hot water which would be completely redundant

Is a system boiler a good middle ground? I know it'd make the new pump redundant but it should improve water pressure, allow us to get rid of everything in the loft and still work with the Solar iBoost.

Or is it best to just replace the boiler like for like? Thank you

jk0

Like for like IIWY.


Combis are okay if you only ever need one tap on. Plus mine takes an age to run the hot water.

Biggus_Dickus

blizeH wrote: »

Hi,


We need to replace our old Ideal Classic boiler as it's kettling on an almost daily basis. We have a 4 bed house with 2 bathrooms, though just 1 shower is ever used at a time.

I'd like a combi boiler because:

• It'd let us remove the water tank in the airing cupboard, and all of the stuff in the loft.
• It'd greatly improve our water pressure, which is very poor at the moment
• I'm guessing it's much more efficient to only heat the water we use

However:

• We've just replaced the heating pump to try to fix the kettling issues
• We have a Solar iBoost for hot water which would be completely redundant

Is a system boiler a good middle ground? I know it'd make the new pump redundant but it should improve water pressure, allow us to get rid of everything in the loft and still work with the Solar iBoost.

Or is it best to just replace the boiler like for like? Thank you

With due deference to the wonderfully helpful and knowledgeable members on this MSE forum you could cast your net further and post your question on more specialized Central heating forums such as the UKPlumbers forum and the DIYnot forum.

https://www.ukplumbersforums.co.uk/forums/central-heating-forum.21/

https://www.diynot.com/diy/forums/plumbing/

I use these sites quite regularly and I find them extremely helpful. I’ve had a combi boiler problem just last week which I sorted out myself after receiving expert guidance from a GSR engineer on the UKplumbers forum.

The UKplumbers forum gives you access to professional ‘Gas Safe Register’ (GSR) heating engineers and not just DIY’ers.

If you receive a reply from a UKplumbers forum member and they have the tag ‘GSR’ (on their profile) you know the advice is coming from a registered engineer as opposed to a DIY’er.

The heating engrs are carefully vetted before the website grants them the ‘GSR’ tag. The DIYnot forum is also very useful.

blizeH

Thank you! I've got a couple of plumbers coming out to give us quotes for a new boiler so I'll pick their brains, if they give conflicting info I'll definitely post on those forums too


(one should have showed up an hour ago, no word from them yet... gotta love trades people!)

Rodders53

System boiler.

Less to go wrong, longer life. You already have the plumbing/controls, and can still have HW if the boiler packs in via iBoost and/or mains electricity.

iBoost gives 'free' HW from a renewable source, why would you decide to stop using this capability?

If you want higher HW pressure for showers, then you need to go unvented HW tank (iBoost can still work with one). But that will cost a fair bit more money. (But you will lose all the loft tanks/pipework).

blizeH

Thank you Rodders! System boiler definitely seems like a good middle ground. Annoyed with myself for just buying the new pump though

blizeH

Annoyingly with three different quotes we had someone strongly recommending like for like, someone strongly recommending combi and someone recommending system

jk0

Like for like is the simplest option isn't it?


No expansion vessel to worry about?


BTW, to improve water pressure, you can build a higher platform for the loft tank.

ianto11

Biggus_Dickus wrote: »

https://www.ukplumbersforums.co.uk/forums/central-heating-forum.21/

https://www.diynot.com/diy/forums/plumbing/

I use these sites quite regularly and I find them extremely helpful. I’ve had a combi boiler problem just last week which I sorted out myself after receiving expert guidance from a GSR engineer on the UKplumbers forum.

The UKplumbers forum gives you access to professional ‘Gas Safe Register’ (GSR) heating engineers and not just DIY’ers.

If you receive a reply from a UKplumbers forum member and they have the tag ‘GSR’ (on their profile) you know the advice is coming from a registered engineer as opposed to a DIY’er.

The heating engrs are carefully vetted before the website grants them the ‘GSR’ tag. The DIYnot forum is also very useful.

In this world of litigation we live in, I'd be hugely surprised if anyone with the relevant gas safety tickets would pass on technical info to DIY'ers as misconstruing that info..has serious repercussions

macman

Basics: how many bathrooms or showers will the boiler supply?
If your mains water pressure is poor, a combi will not help. Did you mean your flow rate from the existing tank?
Remember that a combi cannot supply any CH heat when it is supplying DHW.
PS: you don't need a plumber, you need a GSR RGI.

Cardew

Biggus_Dickus wrote: »

With due deference to the wonderfully helpful and knowledgeable members on this MSE forum you could cast your net further and post your question on more specialized Central heating forums such as the UKPlumbers forum and the DIYnot forum.

With due deference to knowledgeable GSRplumbers, opinions amongst that fraternity, on the question posed by the OP, would be as varied as the members of this forum.