How many vent pipes are required on an open vent system.

[PeedOftec]

I've seen this post before and done a drawing how it should be connected.

The heat leak is connected as per the drawing now.... and the plumber fitted a lever valve too (not on vent thankfully!)

 

[PeedOftec]

The pump over is because the cold feed is wrong.

Yes, I closed the tap on the cold feed and it all but stopped, not quite, but very very close. (The water was probably still expanding in the whole CH system and sending a bit over TBH.)

Cold feed is on the oil boiler return as it leaves the tank. The oil boiler circulation pump is just as it goes INTO the tank.

The pump over is from the wood stove vent, not the oil boiler vent.

The wood stove vent is tee'd off the top connection into the tank on the wood stove flow.
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[doitall]

And what do you think will happen if you cap the vent.

 

[PeedOftec]

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And what do you think will happen if you cap the vent.

If I capped THIS vent it would airlock. However it would "expand" out of the other vent (on oil circuit)

Was that the correct answer? (feel like I'm being tested here! LOL)

Can I have my HETAS certificate now please.... LOL...
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