Green Building Forum - MVHR drainage: icicles Tue, 19 Dec 2023 08:22:47 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299216#Comment_299216 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299216#Comment_299216 Mon, 12 Dec 2022 16:57:29 +0000 wookey
http://wookware.org/pics/online/greenbldg/iciclezoom.jpeg

I remember carefully sloping the vents through the wall to drain outwards if there was any water in them, but I'm wondering if that was the right answer now, because there is an internal drain in the machine, so having the condensation drain internally might be better than having it dripping down the wall/render outside. I can't remember if I just made that up or read it somewhere. I think it was recommended.

I had already adjusted the vent grills to be stepped out a few mm from the render surface so that any condensation dripped rather than ran down the wall making a stain, so I already knew that at least some of the time condensation occurs.]]>
MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299218#Comment_299218 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299218#Comment_299218 Mon, 12 Dec 2022 18:00:13 +0000 WillInAberdeen
Our family probably generate 10 kg of water vapour a day (two gallons if it were all condensed) so it seems like only a small proportion of that actually does condense in the MHRV. If it did, the MHRV would recover substantially more heat, but the incoming air doesn't have enough heat capacity to achieve that. The heat recovery % numbers they quote on the datasheet only refer to the sensible heat, they ignore the latent heat, despite that being about the same amount of heat loss.]]>
MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299222#Comment_299222 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299222#Comment_299222 Tue, 13 Dec 2022 08:25:50 +0000 borpin
This will be the same issue as Gas Boilers condensate drains.

Letting the vents drain internally might not be a good idea as the water draining back might end up in the fans.

That in itself is an interesting thought as my vents are vertically above the unit. Mmm need to check as I'm having issues with condensation and my unit and had issues with the fan in the old unit failing.]]>
MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299223#Comment_299223 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299223#Comment_299223 Tue, 13 Dec 2022 08:46:57 +0000 WillInAberdeen MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299227#Comment_299227 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299227#Comment_299227 Tue, 13 Dec 2022 20:52:43 +0000 borpin Posted By: WillInAberdeenJust to add, the cold air is very dry so we need less volume of ventilation than usual.MY issue is CO² and the limiting factor on the ventilation rate I need. I'd also be wary of condensation inside the unit from the cold outside air with it stopped.]]> MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299267#Comment_299267 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299267#Comment_299267 Sat, 17 Dec 2022 06:00:49 +0000 cjard
So long as the ice hasn't blocked yoir drain it'll be ok..]]>
MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299270#Comment_299270 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299270#Comment_299270 Sat, 17 Dec 2022 11:59:18 +0000 bhommels MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299368#Comment_299368 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299368#Comment_299368 Fri, 23 Dec 2022 15:49:36 +0000 jms452
Our 22mm MVHR condensate has a 4m run then drips onto an external roof and it does ice up in cold weather.

After the first winter I made a 12V 24W heater that heats the external pipe for half an hour twice a day that fixed it]]>
MVHR drainage: icicles http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299401#Comment_299401 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17664&Focus=299401#Comment_299401 Tue, 27 Dec 2022 13:23:28 +0000 borpin