Setting up MVHR

[Arudge]

Hello all.

             I've finally got my Vent Axia sentinel B MVHR unit running. My BC wants paperwork so I've no doubt they will want a calibration certificate for whatever device I use? Right now I have nothing, do those cheap vane type meters on fleabay actually work or are the hot wire variety better?

[Arudge]

I spoke at length with a civil engineer friend about anemometers and MVHR, in his opinion the Testo 405I hot wire variety wouldn't be much good because of all the eddy currents set up by the diffuser, they were more for consistent and stable air flows found in in-line duct work, and even then there was a set procedure to the sampling. The link below gives a demonstration.

 

  

 

 

In his opinion, the vane type was the only option. But here i learned something new. The supply and extract vents set up different eddy currents, that's why the Testo 417 come with optional two completely different funnels, one square and one round. There not for round vents and square vents, there for extract and supply. So making your own funnels may or may not give you the desired results. The link below gives an explanation.

 

 

 

 

Hopefully this may be of help to others. 

 

Everyday is a school day.

 

Andy.

 

 

Edited November 11, 2023 by Arudge

[Arudge]

Just to add, i do not work for, or have any affiliation with Testo. I chose them because they appear to be the industry standard.

 

[JohnMo]

I used a Testo hot wire in an duct to set up my MVHR, then got a man with a certified instrument to officially commission and give me a certificate for BC.

 

Only one terminal need a very small adjustment. So nothing wrong with hot wire, as long as you take your time etc..

[Arudge]

Good to hear. I have zero actual experience so real live setups are always going to trump what anybody can dredge up from the net.

Thankyou.