Capping off a vent pipe

[Bunker]

F&E tank, big house, full of slime, vent capped off. Why would someone do that? Boiler wired up weird too, on HW, tank stat opens 2PV but doesn't turn boiler on, valve only wired to the stat.
Any logic in this? Cable runs are easy, boiler directly below cylinder.
Cheers

 

[Reg Man]

Would be very concerned if the open vent is capped off. Probably piped up wrong so it pumps over. As you have already hinted on, the DHW stat and zone valve should be interlocked with the boiler.

 

[IDCHAPPY]

Rip it up and start again. .... love that song

 

[Killy Bing]

Pumping over .
is the feed 22mm?

if so they might have decided it would be fine as combined feed and vent.

as for the wiring..... Idiots

 

[AWheating]

maybe the system was orignally solid fuel? hence the stat to 2port wiring?

 

[Ermintrude]

Nope if sold fuel grav 28 onto cyl no 2 ports. Sounds like a good old DIY job!

 

[Bunker]

I decided I would try and work out a re-wire but got very confused....turns out the cylinder stat does interlock with the HW pump but not the boiler. There are 2 heating zones each with a pump and a 2PV. No air stats anywhere (tpv's on each rad though).
I tried to explain to the custard why it was inefficient but found myself babbling incoherently.

 

[Ermintrude]

Right old mess