MVHR - or?

[Yvonne]

Hello there

newbuild @warrant stage. I have built before and installed ASHP/MVHR, SIP build. This time SIP build but I am struggling with the ventilation as I felt the last system was noisy and I could not sleep with it on.  Is there a website? That would list MVHR by noise output 0r what else could I install. Bungalow 3 bed. Most manufacturers indicate theirs is the best but end user May be more honest. Thanks for taking time to read. 

[JohnMo]

If it's noisy it's a good indicator that the unit was either undersized or the ducting was not correctly sized or installed badly.

 

MVHR should at normal flows be almost silent.

 

I think you are looking for the wrong information, getting the design right is key, a quiet unit badly installed will be noisy 

[Mike]

1 hour ago, Yvonne said:

Is there a website? That would list MVHR by noise output

 

Yes, but only for units independently assessed for the Passivhaus Institute: https://database.passivehouse.com/en/components/list/ventilation_small

 

However, as @JohnMo says, your previous experience could also have been due to other factors.

[jack]

@Yvonne, do you know what speed your original unit was set to run at? If set for the normal statutory flow levels it could well have been running faster than actually required.

 

Generally, I think most have found that the statutory rate is far higher than needed. As a guide, I generally run mine at just below half the rate suggested by the rules.

[Nickfromwales]

2 hours ago, Yvonne said:

Is there a website?

Yup, you've just found it  Welcome aboard!  

I've always used box attenuators for silencing, plus I'm always over-generous with duct runs ( doubling-up where others would run a single ) and I've ALWAYS been an advocate of installing the next size up unit vs what is required. 

I've used one cheap bag of shit from EsaveP which was a boat anchor, and then went to Brink ( which are Passivhaus certified ) and haven't looked back. If a job needed a 325 ( with 160mm connections ) I would simply jump to the 400 ( with 180mm connections ) so I could reduce the fan speed for the same duty.

My clients have always, without exception, reported that the units run absolutely silently and still maintain excellent air quality / function very well.

 

As said, the best equipment can be installed poorly ( mostly through lack of mitigation by design ) so choose well when making the final selection. And yes, salesman will always say theirs is the best one. That's been happening for centuries  

[jack]

@Nickfromwales, the issue here is that this is a replacement unit. While a quieter unit will help, any installation issues (e.g., lack of attenuators, undersized ducts) won't be fixed.

 

There may also be issues of matching the connections of a new unit with the main ducts currently in situ.

 

@Yvonne, can you share some photos of your installation? Do you know whether attenuators have been installed? They'll usually be either a box or a much thicker section of ducting between the MVHR unit and the distribution manifold (big box with lots of smaller ducts coming out of it).

[Sparrowhawk]

5 minutes ago, jack said:

@Nickfromwales, the issue here is that this is a replacement unit. While a quieter unit will help, any installation issues (e.g., lack of attenuators, undersized ducts) won't be fixed.

@jack I'm reading Yvonne's post as saying she's doing a second build, and in the first the MVHR was noisy and she wants to avoid that in the next. But the warranty bit confuses me.

 

@Yvonne who designed and specified the system for the first house?

[Nickfromwales]

21 minutes ago, jack said:

@Nickfromwales, the issue here is that this is a replacement unit. While a quieter unit will help, any installation issues (e.g., lack of attenuators, undersized ducts) won't be fixed.

 

There may also be issues of matching the connections of a new unit with the main ducts currently in situ.

 

@Yvonne, can you share some photos of your installation? Do you know whether attenuators have been installed? They'll usually be either a box or a much thicker section of ducting between the MVHR unit and the distribution manifold (big box with lots of smaller ducts coming out of it).

🙄

 

13 minutes ago, Sparrowhawk said:

@jack I'm reading Yvonne's post as saying she's doing a second build, and in the first the MVHR was noisy and she wants to avoid that in the next.

@jack Do try and keep up, please

 

13 minutes ago, Sparrowhawk said:

But the warranty bit confuses me.

 

11 hours ago, Yvonne said:

newbuild @warrant stage.

@Sparrowhawk Do try and keep up, please  

 

🤣

[jack]

Ha, I shouldn't post last thing at night or first thing in the morning!

[Sparrowhawk]

6 hours ago, Nickfromwales said:

 

@Sparrowhawk Do try and keep up, please  

 

🤣

I have no idea what the warrant stage is. Don't royalty hand them out? 😛

[ProDave]

1 hour ago, Sparrowhawk said:

I have no idea what the warrant stage is. Don't royalty hand them out? 😛

In Scotland, you have to get a building warrant to build.  It's the formal process of building control approving your plans and saying you may start.  Equivalent to full plans approval in England and Wales.

[Nickfromwales]

8 hours ago, Sparrowhawk said:

Don't royalty hand them out?

In lesser quantities then in-house 'pardons', apparently.

[Temp]

Our fan unit is quite noisy close up but we put it in a small loft void above a porch so its outside of the main cavity walled building. Somewhere like a garage roof would be another possibility if you have an attached garage.

 

 

[Yvonne]

Oh well did not realise there would be so many comedians on here. 🤣 Thank you all for your input I will have a read through and digest.  Thank you 

[Nickfromwales]

43 minutes ago, Yvonne said:

Oh well did not realise there would be so many comedians on here.

Shows are every other night, and twice on the weekend.  

[Pocster]

40 minutes ago, Nickfromwales said:

Shows are every other night, and twice on the weekend.  

I’m every night . Back stage especially 

[Adsibob]

On 24/02/2023 at 22:50, jack said:

@Yvonne, do you know what speed your original unit was set to run at? If set for the normal statutory flow levels it could well have been running faster than actually required.

 

Generally, I think most have found that the statutory rate is far higher than needed. As a guide, I generally run mine at just below half the rate suggested by the rules.

Interesting. I believe @jack and I have similar units. I have a Brink Flair 400. Ours was commissioned by CVC and I’m sure they have the statutory amounts. Our air is a touch on the dry side in winter, so maybe I should turn the flow rate down a bit.

 

On the whole I’ve been very happy with it. In the  rooms where we have spent a bit more and have Lindab Airy valves/terminals it is silent . That includes in our master bedroom, en-suite, guest bedroom, study and living areas. In the other bathrooms and in the kids bedrooms we went for the cheap valves/terminals and it is just about audible. It would annoy me if it was in our bedroom like that, but nobody else has complained.

 

Ours only really gets audible in our bedroom and en-suite when it is boosted, but even then it’s not that noticeable.

 

 

[Yvonne]

@Adsibobthank you that is good to know, I found the site mentioned by @Mikehas some good info although a lot to digest. 👍

[Nickfromwales]

11 hours ago, Adsibob said:

I have a Brink Flair 400. Ours was commissioned by CVC

Yup. Those are the weapons of ( my ) choice. 
 

Best to remember that if you’re looking for good results, you should really be looking at kit which is PH approved / compliant. 

[SteamyTea]

13 hours ago, Nickfromwales said:

Shows are every other night, and twice on the weekend

Mine have been cancelled.

Edited February 27, 2023 by SteamyTea

[Pocster]

8 minutes ago, SteamyTea said:

Mine have been cancelled.

Yeah you were never good at / with gags .

[Nickfromwales]

20 minutes ago, SteamyTea said:

Mine have been cancelled.

That's because even Bernard Manning covers his ears when you get going  

[SteamyTea]

12 minutes ago, Nickfromwales said:

Bernard Manning

Do you know what he would be doing now, if he was still alive?

 

Scratching his way out of a grave.