VMC: the pros and cons, advantages and disadvantages

[Obamot]

"Good"what?"Bonne"pub?

Good evening everyone,
a VMI® does not necessarily preheat the air with an electrical resistance. A VMI® is content to bring fresh air into the living rooms (bedrooms, living room), and this air will be brought into the service rooms and evacuated by overpressure (like the air that escapes from a balloon).

For me, this VMI® system has many disadvantages:

-the disadvantages of the VMC double-flux: need of air insufflation = a lot of sheaths (thus high price of gear and manpower), need of + of ventilos (thus electrical conso rising), risk of noise of insufflation in the rooms if the system is not very well designed and very well posed, risk of acoustic bridges by the sheaths between the rooms (rooms / stay, in particular), etc,

- the major disadvantage of the VMC single-stream: no recovery of calories.

The few advantages of the VMI® (possibility of fitting to a Canadian well, slightly overpressure the house) are also found in the VMC DF.

So for me, no hesitation:
- either a "light" installation is made with a VMC SF, with hygro-adjustable vents and variable fan to minimize the need for air renewal,

- Or we install a VMC hygro, which will cost 300 euros more than a VMI® and will recover 1000 or 2000 kWh of heating per year.
more here : http://www.comparerdevis.net/travaux_chauffage.htm
Simple personal opinion, of course.

Well that's it "Servenia" or whatever your real nickname, you are unmasked Sabetna:

https://www.econologie.com/forums/post279611.html#279611

PUB and ... account lock in perspective! Bye...

[dani-wel]

Good evening,
a VMI® does not necessarily preheat the air with an electrical resistance. A VMI® is content to bring fresh air into the living rooms (bedrooms, living room), and this air will be brought into the service rooms and evacuated by overpressure (like the air that escapes from a balloon).

For me, this VMI® system has many disadvantages:

-the disadvantages of the VMC double-flux: need of air insufflation = a lot of sheaths (thus high price of gear and manpower), need of + of ventilos (thus electrical conso rising), risk of noise of insufflation in the rooms if the system is not very well designed and very well posed, risk of acoustic bridges by the sheaths between the rooms (rooms / stay, in particular), etc,

- the major disadvantage of the VMC single-stream: no recovery of calories.

The few advantages of the VMI® (possibility of fitting to a Canadian well, slightly overpressure the house) are also found in the VMC DF.

So for me, no hesitation:
- either a "light" installation is made with a VMC SF, with hygro-adjustable vents and variable fan to minimize the need for air renewal,

- Or we install a VMC hygro, which will cost 300 euros more than a VMI® and will recover 1000 or 2000 kWh of heating per year.
more here : http://www.comparerdevis.net/travaux_chauffage.htm
Simple personal opinion, of course ....

[I Citro]

For me, the VMC simple flow, hygro, or not, would not have improved in rooms facing north and have moisture problems.

The double flow CMV has considerably improved the thermal comfort of these rooms by blowing in new non-humid air "preheated" by the calories recovered from the stale air.

These rooms are no longer wet, the linen does not mold more in the cupboards, more bad smells.

Waiting for me to redo the sidewalks around the house and install drains to evacuate the humidity on the north side.
But before that I have all frames to replace (total removal) and the inner lining that will complete the tightness around the high-performance frames.

[Former Oceano]

As far as power consumption is concerned, my VMC DF has 2 gears and shifts to higher gear when needed. Power consumption of 40W approx.
For the concern of ducts, today it is better to think about its installations (electrical, networks, air, water) before undertaking any construction or renovation work and the renewal of the air must be part of it.

[I Citro]

My VMC has 8 speed adjustment ranges.
I can adjust the speed of insufflation or extraction differently to obtain a differential, in general we set a slight overpressure (10% in my case).

In general, the CMV operates in 2 stages, normal speed and "presence" speed.
For example, it accelerates in the morning before and during the shower ...

The consumption of 2 cumulative fans oscillates between 25 and 40W but the total consumption can exceed 1000W during certain periods when the electrical resistance is activated to prevent the icing of the exchanger (it is rare for me).

I have an energy meter connected to my VMC and I take monthly readings to check the operation.

I prefer to know the monthly and annual consumption as well as the impact on my electricity bill.
My instant conso is less strategic for me.

[Link]

Answer to the subject:

FOR obviously. She :

- Clean the air of the whole house (kitchen, bathroom, toilet, pollution due to household products etc ...)
- Prevents moisture formation
- Ensures the renewal of air
- Recovers calories from the extracted air instead of recovering cold air directly outside winter in the case of a double flow.


By cons a VMC, must be installed correctly, taking into account imperatively these points:

- Put the supply and return network in the right parts
- The precise position of the mouths in these
- The good flow of the mouths according to the parts
- The type of mouth: blowing, recovery, self-regulating, humidity-controlled, silent, low induction ect ...
- Isolated ducts (against noise and condensation)
- The acoustics of the network (need to trap sound and other ..)
- Take a VMC preferably high efficiency, with good features, programmable, multiple speed and has the freecooling mode

Many people take the CMV installation not seriously enough and end up in many problems
while a well chosen and well made installation is really a big plus in a home.

[LOGIC12]

Hello, For those who have vents on shutter boxes and feel the cold air, which is very uncomfortable, here is a link that can help:

https://www.youtube.com/watch?v=3xgc90h8A4Y

I did this in a small rental apartment where the tenant complained that he really felt the cold "falling" from the ventilation.

Since, it does not have this sensation of cold any more, it is probable that the air warms up a little bit and it does not grow, it simply passes the necessary air to the VMC. I made the box much larger than the one shown on the video, especially since I had a lot of room, I even put two deflectors, on each side of the air intake on the casement of the shutter but quite far from the air inlet.

Unfortunately this system is only applicable in this case.

[chatelot16]

I saw previous messages that give the advantage of the VMI, but forget a catastrophic disadvantage

the VMI puts the house in overpressure and brings out the hot and humid air by all the leaks: great chance to fill the insulation of moisture ... it is absolutely necessary that the inside air can leave without passing in the insulating

the conventional VMC may be the disadvantage of making visible cold air flow, but if there is air passage in the insulation it will be cold air so drier when it warms in insulation

for the cold draft effect of conventional VMC air intake vents, it must be directed to the ceiling to dilute the cold air into the warm air and make it go unnoticed

you must also check that the aeration has a flow limiter that works well, is not blocked by dust or paint

of course the VMC double flux reduces the loss of energy, so with double flow or can ventilate more without wasting ... with the simple flow it is necessary to really limit the flow to what is neccessary

[LOGIC12]

Hello, If we rent a house, it is more prudent that it be equipped with a VMC. Indeed, it is not certain to have someone conscientious that will evacuate the water vapor that produces: kitchen, showers, clothes that dry inside.

Some even want to dry clothes in the home and found that the vents bring cold .... But how the laundry could dry with air saturated with moisture.

So the laundry has trouble drying, and bacteria thrive in it, so the laundry "stinks", and we think it comes from the machine ..

In order for the laundry to be healthy, it must of course be a well-maintained machine, leave the drum open so that the water that remains in the bottom does not rot, often clean the filter, but it is also necessary that the laundry can dry the most quickly possible. The ideal would be to have a clothes rack in a windy place, but sheltered from the rain. And in a pinch, we finish the drying inside.

Given the humidity that is produced by the occupants, if we do not pay attention, and if we are afraid to open because of the cold, it is the disaster in the house. Have not you noticed: we have never heard so much about unhealthy housing. Except for dwellings on the ground floor with capillary lifts, a properly ventilated dwelling, either manually or by VMC, must not be unhealthy.

Some people have occupied their home for 30 years without any problem, they rent it, and there, problems arise, look for the error. And sometimes, no problem with two or three tenants, but with the next, suddenly, there is mold ....

[vinetvinyls]

Bonjour à tous
I'm glad to be part of this forum and more generally to be registered on this site
I find overall the comments (and advice) rather good quality but (there is a "but" lol) it lacks, to my taste, costing ... text explanation: let's stay on the "simple" CMV or "double" it would be interesting to know the volume of air extraction per 24 h the proportion of stale air which "remains" in the house (in other words the renewal of this one) and the loss (there we laugh less) heat so dough! As for me, I “did without” VMC but I ventilate my house like crazy, in light, several times a day; therefore, I am neither for nor against - it is necessary to make "work" the trade - but I introduce a new element in this "debate": the quantification and in more general term a system of evaluation of such or such installation, mechanism, etc etc (like that reminds me of the fan "associated" with a wood stove lol)

Sincerely