MVHR 2023 Recommendations

[Lexifir]

Hi all -my first post.

 

I spent some time reading through the MVHR section whilst waiting for approval, but still have a few questions.

I've got my first self build project on the go (pre-fab timber frame) and am now at the stage of looking through MVHR systems (and a lot of other stuff). There seems to be a general dislike for the cheap plastic tube and conduit in favour of the steel or the rigid plastic semi flexible tube... So far the arguments seem fair enough and the ribbed \ semi-rigid tube seems to have a best of both, which is what I am leaning towards.

Is there anyone here who would recommend their MVHR system (brand) and why they would recommend it.

 

Also - I'm looking at a slightly smarter home with each of the rooms having its own temp, humidity and CO2ppm sensor (I've got several already running in a rental house). All the sensors are linked to a Home Assistant interface, and I'd really like each zone on the MVHR to be automatically controlled.... i.e. if the system detects that the kitchen or bathroom are in use (*because humidty or CO2ppm goes up) then that individual zone would get a boost.

Are there any MVHR that allow automatic activation of zones?

Any recommendations or pointers in the right direction would be appreciated!

 

Thanks

[Nickfromwales]

Hi.

Firstly I would completely discount your experiences with the rental and what you have there, which I assume is a retro-fit system into a property which is not airtight at all and has trickle vents / leaky doors and windows / structure / cold ventilated roof etc etc. We can only advise for the property that this system is aimed at  

You cannot manipulate single spaces unless it is by temperature, by inclusion of inline duct heaters in each room. A single fan provides airflow, so different air speeds are only decided upon commission, so the system can  be balanced. Once set, each space gets a set input or extract volume of air, and the whole house is either on trickle or boost.

There are other types of system that may be of better compatibility to your current remit, but before anyone can advise further we would need to know a few things first; type of dwelling - airtightness score if airtight - is MVHR mandated or a choice purchase?

[JohnMo]

If you are installing MVHR just keep it simple. Push buttons for boost in wet rooms. Set the flow rates per building regs, until sign off, then reduce based on number of people in house. 90mm semi rigid, to easy to install, minimum number of runs and quite.

 

Titon HRV, are good, made in UK with good technical and spares support. I had an issue and they were great. No call centres or people who have never seen a unit, trying to talk through a problem, like most companies these days.

[joth]

Just boost the whole house if high humidity or CO2 is detected. What benefit are you trying to seek by doing it per room? The heat recovery efficiency gain will be miniscule and far outweighed by the losses introduced by need for the MVHR to have per-room fans and baffles.

 

Humidity is automatically handled by many units (like my Q350) and I really don't think CO2 should be necessary, log it by all means but if you find it's regularly going out of comfortable range you should increase the ventilation rate all the time, not rely on dynamic boost.

(One thing I do do, fwiw, is put the whole system into eco/standby trickle rate when no one is home - as determined by the house alarm being armed).

 

 

 

Edited May 30, 2023 by joth

[JohnMo]

1 minute ago, joth said:

One thing I do do, fwiw, is put the whole system into eco/standby trickle rate

I did that with mine about 3 months ago, we have CO2 monitors for Scottish building regs,  nothing undue has happened to CO2 levels, boost never or very rarely comes on. All is good so it stays in away mode all the time, the setting is mid way between minimum flow allowable and current set point.

[GaryBixhall1984]

My Adroit DV96 from Airflow is actually a Finnish built unit, and I cannot say I have masses of experience but I had a Nuaire previously and found it pretty basic / parts super expensive, hence I replaced it.

 

I control the unit from my phone using their cloud services, its super comprehensive, with detailed data. I really love it!

[CalvinHobbes]

On 30/05/2023 at 18:53, GaryBixhall1984 said:

My Adroit DV96 from Airflow is actually a Finnish built unit, and I cannot say I have masses of experience but I had a Nuaire previously and found it pretty basic / parts super expensive, hence I replaced it.

 

I control the unit from my phone using their cloud services, its super comprehensive, with detailed data. I really love it!

What sq footage is your home? We are around 2000 sq ft and we need to sort this out. Have you checked out prices for spares for it? Good point about Nuaire.

[GaryBixhall1984]

1,100 sq ft - but Airflow make much bigger units too. Parts super reasonable online.