Green Building Forum - Velux Active? Tue, 19 Dec 2023 08:25:29 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275388#Comment_275388 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275388#Comment_275388 Thu, 05 Sep 2019 14:37:15 +0100 HoveTom
I’m converting a bungalow with major renovation and a new roof. I’m installing several Velux windows upstairs as planning dictated I can’t have dormers.

Has anyone tried Velux Active home monitoring and ventilation? For those that don’t know it’s an add on to electric Velux windows. It comes with a sensor which monitors humidity, CO2 and Air Temperature and regulates them to your settings through the Velux. Apparently recovering up to 75% of the heat from the out going air in the process. It’s £180 odd for the first kit and then £70 odd for further rooms.

This price seems very reasonable and much cheaper and easier to install that all the ducting involved in other MVHR systems. I have ruled out ducted MVHR as my property isn’t being built with strict air tightness in mind and due to difficulty running the ducts with it being a bungalow conversion. I am however very interested in Aereco products.

Does anyone have Aereco house ventilation? If so what kit and how do you find it, is there a noticeable difference? I appreciate this Velux system would only do the bedrooms and the Aereco system does the whole house but for the cost it can’t be ignored..

Any help or thoughts much appreciated.

Tom.]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275391#Comment_275391 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275391#Comment_275391 Thu, 05 Sep 2019 19:10:00 +0100 andyman99
"The smart ventilation unit is installed above the VELUX roof window on the outside of your home, is invisible from inside and delivers over 75% heat recovery of the exhaust air"

I'm a little sceptical how it can do that when the outside temperatures start to drop?]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275392#Comment_275392 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275392#Comment_275392 Thu, 05 Sep 2019 20:13:23 +0100 djh https://www.velux.com/products/ventilation/velux-smart-ventilation They say 'Fits most MK sizes of our top-operated roof windows'. What does that mean? I take it to mean top-hinged but there's a picture of a woman accessing the unit with the top of the window outside the frame? And the schematic of a man installing it seems to imply the sash has to be removed altogether?

I'm impressed by the low price, but I don't understand why subsequent units would be so much cheaper than the first?]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275394#Comment_275394 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275394#Comment_275394 Thu, 05 Sep 2019 21:11:28 +0100 tony
???]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275395#Comment_275395 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275395#Comment_275395 Thu, 05 Sep 2019 21:26:38 +0100 djh Posted By: tonyAs far as I can see all the do is let (hot) air out in greater or lesser amounts.
The page I linked to explains the mechanism. It's the same idea as an enthalpy wheel, though less efficient. I've seen other devices using the same idea but I don't remember which.]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275397#Comment_275397 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275397#Comment_275397 Thu, 05 Sep 2019 22:09:56 +0100 WillInAberdeen
'MK' is velux's product code for their range of 78cm wide windows - MK06, MK08 etc - the width that fits the MHRV.

'Top operated' means the handle is at the top and the hinges are in the middle, also called 'centre pivot', like in the picture. Their 'top hung' ones open at the bottom for greater headroom or escape, but wouldn't work with the mhrv.

Confusingly, the 'velux active' name in the UK seems to be used for a completely different product, an internet controller that interfaces with their electric window openers to open the windows if the room is too hot, as Tony said. The first room needs a temperature sensor and an internet gateway. Subsequent rooms just need a temperature sensor so cost less.

I couldn't immediately spot the mhrv on sale in the UK despite it having the same name 'velux active' on their international website... Anyone?]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275399#Comment_275399 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275399#Comment_275399 Fri, 06 Sep 2019 13:20:41 +0100 Rex
As far as I understand things, MVHR is designed to provide a cross-flow of air in a room. Surely this will only supply / extract air in a very limited space and most of the room will not benefit from fresh air as eddy currents will establish.

Additionally, I assume that this require power. How many roof lights have a power source close by?]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275403#Comment_275403 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275403#Comment_275403 Fri, 06 Sep 2019 15:20:33 +0100 GreenPaddy
Looks like a great idea, essentially an MVHR using an existing structural opening. We (the wife) often have our velux vents open, so this would help ameliorate my naval gazing obsession with drafts.

People often have lights in their ceiling, (if there's a flat area of ceiling), which would likely be near the head of the velux, so getting power to it retro. might not be such a big deal.

BUT...an MVHR outside of the thermal envelope? Do we take the over 75% heat recovery at face value? What's the cost per unit? What are the flow rates?

If it's sub £300 say, I would deff suggest it for any clients with velux in a bathroom, and poss in a bedroom. On the subject of flowrates, it would need to be around 8 litre/min, for a const running, to replace an intermittent for BRegs, and this theoretically should be better than an intermittent, for "cleaning" the room.

Looking forward to understanding more...]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275404#Comment_275404 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275404#Comment_275404 Fri, 06 Sep 2019 17:01:31 +0100 djh Posted By: RexAs far as I understand things, MVHR is designed to provide a cross-flow of air in a room. Surely this will only supply / extract air in a very limited space and most of the room will not benefit from fresh air as eddy currents will establish.
That's how things like Fresh-R work though, isn't it? and they seem to get by. I suppose there's more mixing with the rest of the air inside takes place than we expect.

Additionally, I assume that this require power. How many roof lights have a power source close by?

Is it not solar-powered?

Posted By: GreenPaddyBUT...an MVHR outside of the thermal envelope? Do we take the over 75% heat recovery at face value? What's the cost per unit? What are the flow rates?

I worry about the outside location as well, but I suppose we just have to trust they've insulated it sensibly. Ditto with the 75% claim; it's not outrageous, since the best units claim over 90%, but Velux would be staking their good name if they don't have any evidence. I didn't immediately see a cert on the website though.

TBH, the web page looks like a pre-announcement (aka vapourware). Trying to find it in the shop seems to be impossible. There don't seem to be any documentation links, nor customer references etc. It's all a bit new.]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275405#Comment_275405 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275405#Comment_275405 Fri, 06 Sep 2019 17:36:09 +0100 WillInAberdeen
Would really be great for retrofits, velux have been selling that size window for decades so there must be a huge number installed and waiting for an easy retrofit mhrv solution.]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275452#Comment_275452 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275452#Comment_275452 Mon, 09 Sep 2019 18:11:03 +0100 HoveTom
I asked what would happen for three quarters of the year at night when the outside air temp is below what most would desire in the bedroom if the C02 levels become high? Answer - The window stays shut. Same for humidity. So basically nothing happens. I asked if I could do without a bathroom extractor if I had one of these in a bathroom Velux and the answer was no, for the above reason that it wouldn’t be practical.

It can open a vent instead of the whole window at times but this is basically just a trickle vent so without any sort of fan to assist it could take a while to clear the air from a room.

Hope this helps someone considering this. I may have understood the system wrong so do double check yourself.]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275453#Comment_275453 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275453#Comment_275453 Mon, 09 Sep 2019 18:53:23 +0100 GreenPaddy
Cut/paste this link.
https://www.velux.com/products/ventilation/velux-smart-ventilation

This clearly discusses fans, fan speeds, heat recovery, etc. There are other UTube vids too.

Velux "Active" is the simple vent opener. This is something quite different, by description, even if it's just a twinkle in velux's supply chain eye.]]> Velux Active? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275543#Comment_275543 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16232&Focus=275543#Comment_275543 Fri, 13 Sep 2019 14:49:38 +0100 HoveTom
They can however take your order for it. Prices are for the 780mm frame size £644, 942mm £643 and for 1140mm £702 all plus vat.

Difficult to buy when they can’t answer any questions on it at this stage. You’d have to get In touch with Velux in a mainland European country which sell it to get technical (or even fairly basic) answers.]]>