Silencer - can it be mounted horizontally?

[Weebles]

We have a Vent Axia MVHR and are currently fitting the unit and associated metal ducts. The drawing from BPC specifies the silencer to be mounted vertically. No space for that in current position. Can this silencer be mounted horizontally please?

[Cpd]

I really don’t think it will make any difference at all, but will wait to see what others say. 

[Bitpipe]

We didn't bother with silencers and took a wait and see position - if I did fit one it would be horizontal.

 

I have a supply vent more or less above my head in bed - didn't quite think it through. On normal flow it's pretty silent but when boost kicks in there is a slight drone which, if i'm awake in middle of night is noticeable.

 

Now normally that only happens when someone goes to loo in the night (bathrooms have PIR to trigger boost) and was also how I discovered that one of the kids PIRs had failed 'on' a few weeks ago.

 

Anyway, surely only the supply path to rooms needs silenced? Why would you silence the extract path?

 

This may be a long winded way of saying I may buy one of your silencers from you !

[Jeremy Harris]

Silencers work in any orientation, so horizontal is fine.

 

Based on my experience, I'd definitely silence both extract and supply.  Our noisiest terminal before I fitted silencers was the extract in the utility room.  It's a short duct run, and the fan and compressor noise from the MVHR was very prominent until I fitted the silencers.

[oranjeboom]

Well BPC only supplied me with one silencer, so hope that is sufficient! I have no option but to fit mine horizontally.

[Pocster]

Yep I checked this as it was an option for me . Vertical or horizontal no issue .

Edited October 15, 2019 by pocster

[NSS]

Either or. We have one fitted vertically but the rest horizontally. Our silencers are a minimum of 60cm long so I'm not sure how anyone could expect them to be fitted vertically between two floors.

[Weebles]

On 13/10/2019 at 20:38, Bitpipe said:

This may be a long winded way of saying I may buy one of your silencers from you !

 

Like @oranjeboom BPC only supplies one silencer and based on the responses here I reckon we’ll be using it, fitting horizontally ?

I guess you can retrofit one?

[jfb]

I retrofitted one. But as always normally easier to do it first time round!

[Jeremy Harris]

+1 to the above.

 

I retrofitted silencers to both extract and supply and it would have been a heck of a lot easier to do during the original install.  Given that silencers aren't that expensive, I'd be inclined to always fit them, even if you think you may not really need them.

[vivienz]

I'd silence every part I could. Ours has been in for a couple of months now and is located in the loft space above the upstairs landing and our en suite. On any setting above the lowest fan speed, the noise from the unit is like being on a car ferry when it revs its engines up. It's especially noisy when the integral cooling pump comes on - quite thunderous in the en suite and enough to keep you awake at night in the adjacent bedroom.

[NSS]

3 hours ago, vivienz said:

I'd silence every part I could. Ours has been in for a couple of months now and is located in the loft space above the upstairs landing and our en suite. On any setting above the lowest fan speed, the noise from the unit is like being on a car ferry when it revs its engines up. It's especially noisy when the integral cooling pump comes on - quite thunderous in the en suite and enough to keep you awake at night in the adjacent bedroom.

Literally can't hear ours running, even on boost. That said, ours runs in Lindab spiral ducting with silencers adjacent to each vent and exhaust fitting. We also 'isolated' the ducting and silencers by mounting on soft rubber blocks to mitigate any vibration/sound transferring to the timber frame/structure.

 

It's so quiet I occasionally hold a tissue against the vents to make sure it's still blowing/sucking!

Edited October 16, 2019 by NSS

[vivienz]

13 minutes ago, NSS said:

Literally can't hear ours running, even on boost. That said, ours runs in Lindab spiral ducting with silencers adjacent to each vent and exhaust fitting. We also 'isolated' the ducting and silencers by mounting on soft rubber blocks to mitigate and vibration/sound transferring to the timber frame/structure.

 

It's so quiet I occasionally hold a tissue against the vents to make sure it's still blowing/sucking!

 

Mine was supposed to have had more silencing things added to it, but they weren't done. There are a few things that need remedial work, so I will add this to the list.

[Jeremy Harris]

I've found that our Genvex is silent when running normally, but there is some flow noise when it boosts.  The main noise issue with it was from the compressor motor.  Whenever that runs it is audible in our utility room, which is directly underneath where the unit is mounted, and audible in the services room.  Silencers probably won't have much impact on that noise, I think, as it mainly seems to be transmitted through the mountings.  I did install the thing on anti vibration mounts, but these aren't, perhaps, as effective as they could be.  This compressor noise doesn't bother us, as the compressor rarely runs at night, and we can't hear it in our bedroom, anyway.

[phatboy]

I only had a silencer on the supply, but fairly quickly added one to the extract as well.

 

The rooms with extract you can tolerate more noise, but it was still noticeable.  £25 later and the entire system is almost silent even on boost.

[Savage87]

What is the best location for the silencers? Is it before the MVHR unit or in between the unit and manifold/distribution box?

[Pocster]

42 minutes ago, Savage87 said:

What is the best location for the silencers? Is it before the MVHR unit or in between the unit and manifold/distribution box?

Stuck mine straight on the mvhr 

 

 

[Savage87]

that's what I'm planning to do, did you get the flexible or semi flexible silencer? Which duct(s) did you connect you're one(s) to ?

[Pocster]

10 minutes ago, Savage87 said:

that's what I'm planning to do, did you get the flexible or semi flexible silencer? Which duct(s) did you connect you're one(s) to ?

semi flexible I think . Zip ties to Mvhr ; then taped throughly ?

From memory ! By default mines a left handed system ; but I’m using it as a right handed system . So both ducts to the right are to atmosphere and from atmosphere; I think !!! ?

[Pocster]

Hmmmm , now I’m thinking I’m wrong and it’s a left handed system looking at my photo . Silencers don’t go on atmosphere side - forgive confusing you and myself !! ?

[Savage87]

reading in the quiet vent brochure, it says:

"It is recommended to install a flexible or solid acoustic silencer between the

ventilation unit and the air distribution box in order to further silence the sound of

the fan."

 

and I've also seen other manufacturers say to fit them on the ducts that go to atmosphere.

So, I'm a bit confused on what the best practive would be.

[Pocster]

48 minutes ago, Savage87 said:

reading in the quiet vent brochure, it says:

"It is recommended to install a flexible or solid acoustic silencer between the

ventilation unit and the air distribution box in order to further silence the sound of

the fan."

 

and I've also seen other manufacturers say to fit them on the ducts that go to atmosphere.

So, I'm a bit confused on what the best practive would be.

Yeah I’m not really helping am I !

I’m 99% certain my silencers are not on the atmosphere side - I’ll check tomorrow!!

[CC45]

just doing this now - the silencer (solid) is going between the unit and the distribution box - can't see why you would want it between the unit & outside.

[vivienz]

13 hours ago, CC45 said:

just doing this now - the silencer (solid) is going between the unit and the distribution box - can't see why you would want it between the unit & outside.

 

Any chance of some action photos? I will be making some changes to our system soon.

[Pocster]

Can confirm as @CC45 said silencers NOT on atmosphere/ external vents .

On site so got photos - forgive own dumbness . Installed it ( though not tested ) so automatically forget all about it and go and learn the next thing !!!