Boiler Air Scoop help

[Plumber69]

Boiler has 2" in and ouput as well as 2 inch supply and return piping. I want to install an air scoop but only have an 1 1/2 air scoop. Will this be ok to reduce it down from 2 to 1 1/2 and then back up to 2

 

[Fitter30]

I'd use it with a bell reducer both ends for better flow.

 

[Sponsor]

 

[Dana]

I'd use it with a bell reducer both ends for better flow.

That's right- bell reducers reduce turbulence and improve flow.


Adding a foot of straight pipe between the reducer on the inlet side of the air scoop improves air purging performance for many/most models. The more turbulence there is when entering the air scoop, the less effective it is (for most).

While fatter pipe=slower flow=greater effectiveness, dropping the diameter to 1.5" from 2" isn't going to be a deal breaker- it should still work.