Joining extracts

[PeterW]

Due to a little change of plan I need to move the MVHR unit - downside is that it will be at one end of the house so I've got to extend the ducting runs accordingly. One that makes no sense to extend though is the dual run to the downstairs wc and utility room as they are next to each other and the wc is 900x1800 and the utility is 1600x2600. 

 

I'm thinking that the wc has the "requirement" to have the higher flow so if I went into there then out of the plenum to the utility I can control the flow pretty well ..? Seems to make sense to do that than run a second 15m run of duct just to do a small room. 

 

@bpc ventilation is this feasible ..?

 

[MikeSharp01]

Sounds sensible, assume the utility is extract as well so all that will happen is that the single duct is, in effect, extracting the two areas. Sphinktering the utility won't work because it is the bigger volume so requires more flow in normal mode as it will have the effect of reducing the flow rate from there in the normal conditions. Have I missed something? You will have to adjust the plenums flow from the WC and the utility in normal mode and just allow the increased flow to come through from both once it all gets going in 'boost'. 

 

Edit. There is possibly also the cross talk issue, where 'noises' from the WC will arrive in the utility!

Edited August 26, 2017 by MikeSharp01
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