Switch to a combi boiler

[Randers123!]

You'd setup the boiler's heating connections to an S-plan. That has two (or more) 2-port zone valves to direct the water as required. As a minimum, one zone for heating, one for hot water.
When there is no call for heating, that zone stays off - and the boiler will just run when needed for hot water.

As already pointed out, you really need someone who knows what they're doing - which it sounds like you haven't had so far.

With storage, you decouple demand (hot water out) from supply (boiler output). The boiler keeps the store full, if demand exceeds boiler capacity then the store makes up the difference - for a while.

As said, an unvented cylinder will do the job. Personally I prefer a thermal store which gives mains pressure hot water - and also allows me to run the heating off the store and decouple that from the boiler, while not having a large pressure vessel full of hot water.

Ok this potentially could be my answer , I’ve tried to find some sort of diagram of a system like this but can’t see anything ? Would you mind shedding some light ?
Also dumb question but could I not just use the hot water feed from the boiler to fill the thermal store/ cylinder instead of having a cold feed. Or will that go kaboom and then also using the heating side of things with the valves to top up the hot water temp

 

[SimonH2]

You've mentioned a lack of space, do you have a basement/cellar ?
If not, is there any space under the ground floor ?
Just looking for an alternative location for your break tank and pump - to free up space for a hot tank (unvented cylinder or thermal store).

 

[Madrab]

Trying to fill and maintain the thermal store with the hot water outlet from the combi wouldn't work, it's not how a store works. Typical thermal stores run at atmospheric pressure and the main water volume is made up by a F&E cistern as and when it's needed, there are no safety release valves, expansion vessel etc. A thermal store works like a Hot water cylinder but in reverse. So the water volume in the store is heated directly from the boilers central heating flow and return and then there are 2 coils within the store - one for the CH circuit (Pumped) and the other for the Hot Water circuit (pumped or mains).

Trouble with stores is that they always have to run hot, typically 10-15deg hotter than the target HW temp, that and we tend to term them as sludge buckets as they can be very difficult to keep clean due to the large slow moving volume of water. They also require blending arrangements for CH out etc to adjust the flow temps etc. That and you would still have to find the space for the store - typically the size of a med sized HW cylinder.

Also if you have a combi then you could also dedicate the hot water outlet from the boiler to a single outlet that was local to the boiler, say a kitchen tap etc. and everything else runs from the store/unvented

 

[Randers123!]

Yes I’m looking at moving the tank boost now into the garage , meaning I can free up big space next to the boiler , which then I could potentially install a hot water tank , I just need to work out how it all plumbs in , and the fact my cold water supply feeds at 3.0bar , so I’m assuming I would still need a shower pump to pull the hot water from the tank.
I’ve been trying to find some diagrams but with no real joy

 

[Johntheo5]

If you opt for a UVC (unvented cylinder) then you don't/shouldn't require a shower pump, you could heat this UVC from the existing boiler heating side and maybe just feed the kitchen tap or one tap, whatever, from the present boiler DHW side but you would need to check the power output in heating mode as its often less than the output in DHW mode, disadvantage of this is that even if the kitchen tap only requires a hot flowrate of a a few LPM is that there is no central heating or UVC coil heating available for this period of time, may or may not be a problem.
You should also "find out" what shower flowrate you require, as this + tap water flowrate has a big bearing on the pump output and pipe sizing, your "3bar" pump only gives this pressure when its pumping zero LPM, if your flowrate demand is 30LPM, say 20LPM shower + 10LPM tap, then that pump will deliver that flowrate but at just over 2.5bar so probably approaching the minimum head required depending on the piping losses and the shower head required to give that 20LPM, if this is the required flowrate. You should/will have to spell it out clearly what flowrates you require to whoever is changing this system.

 

[Madrab]

The unvented cylinder can be supplied by the tank boost. The unvented then supplies all the hot water outlets bar one at the tank boosts output. So no need for an additional pump. The one HW outlet from the boiler would be the closest to it, i.e. the kitchen tap.

Ideally the boiler would be configured to be a PDHW system (X plan), that minimises any recovery time @ the cylinder. Glowworm uses Ebus, same as Vaillant, so it's not as straightforward as OT and I think you need their propriety controls/interface though something that would need checking to confirm.

So no extra HW pump required.

What was the make and model of either the pump and normal shower or the make/model of the power shower itself. That will provide a starting point as to what you had and what's expected.

I’ve been trying to find some diagrams but with no real joy

What diagrams is it you need? This will be a bit of a bespoke setup