Where's the best place to site a heating expansion vessel?

[Jock Spanners]

Evening all,

I'm converting a regular boiler to a sealed system and unvented cylinder. The Megaflow is in the bathroom and the boiler downstairs high on a wall. I'm running the cylinder vent to the soil stack. I'm struggling to decide where to put the expansion vessel on the heating. It's an s plan with the pump and valves next to the cylinder. Should I put the vessel on the primary return or the heating return? Does it matter where the filling loop goes on the return? If I put the vessel near the cylinder can I route the blow off through the tundish from the unvented cylinder? Any advice appreciated.

Jock

 

[king of pipes]

Put it on the common return back to the boiler no valves or controls on the pipe , you will need a seperate pipe run for prv . Kop

 

[Last Plumber]

Evening all,

I'm converting a regular boiler to a sealed system and unvented cylinder. The Megaflow is in the bathroom and the boiler downstairs high on a wall. I'm running the cylinder vent to the soil stack. I'm struggling to decide where to put the expansion vessel on the heating. It's an s plan with the pump and valves next to the cylinder. Should I put the vessel on the primary return or the heating return? Does it matter where the filling loop goes on the return? If I put the vessel near the cylinder can I route the blow off through the tundish from the unvented cylinder? Any advice appreciated.

Jock

Tee the vessel in behind the pump as you would with the cold feed pipe, or if the cold feed is like that already then connect onto that.