a 4 tapping boiler - 1 vent pipe or 2?

[jackecole]

Can somebody please explain something to me if anyone knows....

on a 4 tapping boiler (solid fuel mainly i believe only have 4 tappings) - 2 for the hot water flow and return and 2 for the heating flow and return, is there only 1 vent pipe over the f & e, or can they merge into 1? if 1, from what point can they merge together?

 

[ctp]

depends how you pipe the system, fully pumped or gravity , mi instuctions should tell u what they recomend

 

[jackecole]

Hi again

Sorry... I mean for a sem-gravity system (Gravity hot water).

 

[sambotc]

Take your vent pipe off the gravity circ's make sure it's path is completely unobstructed (inc. motorised valves etc)

Untitled

• sambotc
• 8 Aug 2008
• 4

The radiator in the picture above is a heat leak NOT the pumped heating circuit.

Take your pumped heating flow off the 28mm gravity before the cylinder or from a boiler tapping and take your return back to the boiler return connection using an injector tee (essential)

You will only use 3 tappings this way so plug the other one. You could use the other spare for the vent pipe but normally equates to more pipework.

HTH Sam

 

[ctp]

all a bit antiqated, if manufactures instructions allow it would be better to fully pump the system ,otherwise how can u control the hot water temp in the cylinder it would just boil,but still the system temperiture is not controlled because of the nature of the heat source.

 

[sambotc]

I am presuming it is a solid fuel set up, if so then provisions need to be in place in the event of power failure/pump stop's working to dissipate heat. Gravity h/w is the easiest way to achieve this along with the fact he has stated it already.

Part L still applies to solid fuel also so cylinder stat and zone valve should be introduced. Obviously an effective heat leak is a must.

If it is gas/oil then fully pumped is most certainly the way to go.


Sam

 

[ctp]

in the event of pump failure/overheating a bucket of water next to the fire would be helpfull. lol