System for a Small Cupboard

[ChrisNason]

I've posted before about getting something in a small airing cupboard and the general opinion was a combi like Vaillant 937 (with small store)
The cupboard has a 450mm door but 570mm once inside. It's full height at 2400mm and a depth of 1200mm.
I've had a quote for fitting and they want to include an upgrade of the gas supply to 22mm and plumbing in a 22mm main. The last is the worst problem because it would go along a wall that I was hoping to have clear.
Also the lack of a hot store (cylinder) is an unwelcome result especially as I'd lose the Immersion capability.
However, I've now found McDonald Engineers in Scotland that have a pressured store with dimensions of 420mm x 1650mm for 180 litres of water.
Am I right in thinking I could take this (with it's remote Expansion vessel) and then build a system with a 'Sealed' boiler that would not require any tanks in the loft?
I know it needs some clever plumbing and kit.
Can I get a stack on the far wall that starts with this 1650mm with the boiler over that and then the expansion vessel either above or slightly forward on a side wall?

 

[gas4you]

All sounds good to me, the only draw back in my mind as a service/installation engineer, is getting to screws and bits that I may drop behing the cylinder during a service

For an even smaller boiler, you could go for an open vent model and add an external EV to this. May help

 

[ChrisNason]

All sounds good to me, the only draw back in my mind as a service/installation engineer, is getting to screws and bits that I may drop behing the cylinder during a service

For an even smaller boiler, you could go for an open vent model and add an external EV to this. May help

Great. So it could work.
What's the external EV and where would you put it?

 

[gas4you]

Expansion Vessel, red one, for ch systems, you may find room to squeeze it in the same cupboard.

 

[ChrisNason]

Expansion Vessel, red one, for ch systems, you may find room to squeeze it in the same cupboard.

Ahh. I had the Expansion Vessel in my mind but forgot I would need 2.
So that's one for the closed Boiler system and one for the pressured Hot Water system.
Is there any rule about the various vertical alignments of these? Can both EVs be up against the ceiling above the boiler?

 

[ChrisNason]

Bit more in my training!

I now know you can get a boiler made for a sealed system with all the kit inside including pump, expansion and wiring.

So... It would seem I'm back to the pressured Cylinder on the floor with the Boiler above and then the Expansion Vessel for the Cylinder hanging off the ceiling.
Will it work?