London Leasehold - MVHR repair or replace?

[Mr_Windy_Flaps]

complete newbie to the world of MVHR here...
I have recently purchased a leasehold flat in London constructed in 2017. There is a Silavent HRX MVHR unit in the utility closet that is not working correctly. When the master electrical switch for the unit is switched on, the HRX unit goes what can only be described as full tilt... I can hear the fans spin up to what I  assume is full power as I can hear them wherever I am in the property. There doesn't seem to be any control panel or switches anywhere in the property to control this.
I have been in touch with farmwood.co.uk (new owners of Silavant i think?) who tell me that the unit is no longer supported, and as it is a sealed unit will have to be replaced completely... less that 10yrs old and no support is pretty disappointing.
So, my questions to the forum are:
1) Am I right to take farmwood's response at face value and rip out and replace?
2) If not, and it's repairable, can anyone recommend a service company who can assist in north west London?
3) If its not repairable, what units should I be looking at for a replacement? (property is a 2 bed with ensuite, just under 1000sqft)
Thank you

[Temp]

Found a troubleshooting guide here..

 

https://www.polypipe.com/sites/default/files/hrx_troubleshooting_guide.pdf

 

Suggests cleaning the filters if it's noisy. It also refers to a normal/boost mode and other possibilities.

 

We have a different system and the filters need cleaning about every 2-3 months. Ours can be washed under a tap.

 

Edited March 17 by Temp

[Mr_Windy_Flaps]

3 minutes ago, Temp said:

Found a troubleshooting guide here..

 

https://www.polypipe.com/sites/default/files/hrx_troubleshooting_guide.pdf

 

Suggests cleaning the filters if it's noisy. It also refers to a normal/boost mode and other possibilities.

 

We have a different system and the filters need cleaning about every 2-3 months. Ours can be washed under a tap.

 

Hi, yes I saw this already and have already cleaned the filters, made no difference.

Also found the boost button (as well as the bathroom light trigger/boost function), but the unit still just comes on full tilt.

[Temp]

What tends to happen with mvhr is the bearings eventually fail but they can sometimes be replaced cheaply yourself if you are mechanically minded. 

 

However my guess is its working and stuck in boost mode or just set too high. Presumably there is no obvious humidity sensor? Sometimes they are in a duct.

 

Perhaps ask a few neighbours if they have any experience with the units or who they use to fix them?

 

 

 

 

[Temp]

Here's a really long shot... has the bathroom light been replaced with an LED bulb? Sometimes LED glow faintly when off due to capacitive coupling between live and switched live. I wonder if this capacitive coupling is enough to fool the mvhr into thinking the bathroom light is always on so its alway in boost mode?  Probably not, but if you have an old filament bulb might be worth trying just in case.

 

 

 

 

[Mr_Windy_Flaps]

A quick upadate... after requesting the commissioning instructions from the original manuafacturer, and also finding the electric control box I have established that the fan speed control potentiometers for both normal and boost modes were turned up to the max!.... why?... i have no-idea.

I have now adjusted both pots down to levels where I think the noise of the fans is tolerable.
I have no idea how long the system was set like this but explains why the system was not used by the previous residents.

[JohnMo]

You may need to get the system flow rates set so that you are not either under or over ventillated. Plus you may need to get the individual room flow set so the system is working as it should.

 

 

[Mr_Windy_Flaps]

Yes i guessed this would be the next step...

I assume i would need a flow rate meter to establish correct vent opening size?

Or of course to hire someone experienced who can setup the system?

[JohnMo]

Plenty of reading on here on what and how to do it.