Coanda

I spent some time this afternoon cutting the parts. Careful design means I get it all out of one sheet of polystyrene. Overall size is 800mm by 820. by 485. I've glued up a couple of test pieces with no more nails, and if its a success, I'll do the rest tomorrow. I'm wondering should I use dowels for added strength?

Just for interest, do you have any recommendations, for when the time comes?

Sorry, can you elaborate, I'm not getting that. Edit to say I got it now, Yes that's the plan but any recovery I make is profit since the fans are running anyway to ventilate the place. They've been running 24/7 for the last couple of weeks and I think the RF may be dropping a little, but maybe not because of the fans.

Yes we had a few nice days. But you have to allow for headlines and clickbait. Nowadays every gust of wind has a name and storm warnings every few weeks. There hasn't been a decent storm in this area for 20 yrs. Anyways I apologise. It was I who drifted off topic lets return to MVHR. I shall add a summer bypass if and when needed.

50mm polystyrene. I live in Co Antrim, we don't get summers. Seriously I do have lots of ideas about Co2 sensors etc, but not for a while, need to get it working first. I'd be delighted if I needed a summer bypass but at best it would be only required 2 or three weeks a year.

One of mine is a Manrose and the other looks and acts just like it. If I remember correctly one says 250 m3H but at present it's way out of easy access in the roof space. My plan is to rig this up to see what effect it has and I'm not going to spend unnecessarily until I'm sure of the benefits. Then I can either improve this. most likely. or spend some dosh, not as likely but definitely a possibly. I think they're rated a 30 or 40 watts so not going to break the bank for a month or two.

My intention was to make it with corriboard by I stumbled upon one of these brand new in box for seriously little money, it just didn't make sense to waste time and material making it. Daikin 110635J HEAT EXCHANGE ELEMENT 227x227x383 (climatecontrolsandspares.co.uk)

I'm going to use two inline fans which I already have. I believe filter material can be bought and cut to size. Cheapest I saw, that I would consider, on ebay was over £600. If you don't mind what did you get for £350? I started off with an oblong box but miscalculated the amount of space I needed for the spigots. I may well go back to that. Thank you for your comments

Playing on sketch up before I actually cut anything. I saved a fortune already.:) It's 800mm by 800mm and the ducts are 180mm The core is 227 by 227 by 383

What is this summer thing you refer to? I live in county Antrim.

Would that necessarily be a bad thing?

I'm reading all through the site to gain as much knowledge as possible, so resurrecting this old thread. I had gathered some corri board with the intention of making my own core, but I happened upon one of these. Daikin 110635J HEAT EXCHANGE ELEMENT 227x227x383 (climatecontrolsandspares.co.uk) Brand new in box for not much more than the price of corri board, glue, frame and foam. So I am planning to make a polystyrene enclosure and drive it initially with inline fans which I already have. I'm really keen to make as much as I can not necessarily to save money although that is a welcome bonus, but like my plantation shutters. etc I can say I made that. So any more tips on plenums, manifolds etc welcome.

A utube video I saw from the USA talked about ton units for MVHR or was it aircon.

Thank you one and all. I was very good at math in school but alas, that was a long time ago.

OK I get it now. just having a senior moment.

ok but for curiosity what is likely to happen if the intake isn't insulated? I just meant I would use the existing hole in the ceiling rather than make another one. I'll have to enlarge it some. ok thanks

The red dot in the centre of the kitchen ceiling is where I plan to put it. So it will draw equally from both doors.

Could someone help? If I know there is air flowing through a 100mm duct at .80m per second, how do I compute that to m3 per hour?

I've been planning and I've drawn up this sketch, pretty close to scale. The house is just under 100m2 so a small job really. Points one and two are existing kitchen extractor, three and four are existing bathroom extractor fan. I plan to repurpose the bathroom extract to go to the mvhr unit and install a second extract in the kitchen. I'm thinking probably not a good idea to suck cooker waste into the MVHR? One input in each bedroom and living room. Since I'll have three inputs and only two extracts, should I have an extract in the attic? I haven't decided on the outside exhaust and intake yet. Do I need to insulate the intake or just the warmer output?

There's eight around the roof already, so there is some choice, it would also save putting anymore holes in.

Would it be feasible to supply or exhaust through these on a slate roof.

I guess you guys have heard all these questions over and over but say I put a system in and ventilate the place real well, I know from my short experiment that the Co2 levels will come down, but will, over time the constantly moving air reduce the RH?

I have pretty much decided that,that is the only option. luckily, the house is small, under 100 m2 and the roof space gives access to all rooms. There's even a small attic room boxed of and somewhat insulated.

I bought an old 30s house about 5 years ago. Single glazed sash windows, fireplace in every room, no insulation, T&G floors with ventilated space under. I closed up the fireplaces except one, where I installed a wood burner, cause I have enough free wood for it. I installed double glazing, PVC front and back doors, covered the leaky T&G floors and insulated the roof space. So soon the RH was in the 70s and co2 levels with 2 occupants +cat were in the 2000ppm range. So I ran a dehumidifier to reduce the RH but that doesn't help the Co2. If I open the windows Co2 falls but RH rises. I put some MV in for an experiment. I extract through the bathroom and input to the bedroom. The input fan runs around 180 m3/h. The extract fan doesn't have info on it but I think it's similar. I have a co2 meter which shows over 2000 ppm when the bedroom is occupied by two people and no fan and 800 when occupied by two people and both fans running. I've been running them for a week or so and they don't seem to be having any effect on RH. What should be my next step? Add MV to all the rooms in the house and if it's a success then add heat recovery?

I've joined primarily to gain some knowledge of MVhr systems and their workings. Look out for stupid questions.