Fadec

The system is more or less in place what’s left is the attic pipe manifolds which are in situ plus the alterations for the up stairs landing extract manifold that I’m going to feed into the extract line and have the ability to manually/automatically vari with a motor controlled Bellimo valve. So the cascade system looks to be different with no pipes and a route I can’t take.

Hi Nick thanks for the reply, In all the bedrooms upstairs there is 1 fresh supply plenum in each of the rooms with 2 x 75mm pipes I read that if you positive pressure with more air than what would be extracted so the ensuites for every bedroom have 1 extract plenum with 1 x 75mm pipe and that they are nearer to the extract manifold. Plus as mentioned earlier we could put the 10mm gap under the bedrooms doors to the landing for that alternative path. Good to hear that the dining room will be okay, I was worried a bit that I was putting 3 plenums with 1 pipe to each but will be less audible sounds it could be a good move considering they are main living spaces. I have ordered the plastered in version for those 3 as aesthetically it will look better, picture below. The utility has 1 plenum with 2 pipes but not much transfer of air into it as there is no direct door from the landing into it only the kitchen door which is bothering me a little. the dining room has 2 plenums with 1 pipe each so the same as the dining area will have a lower noise at boost.

Thanks I have some plenums around the house with 2 pipes like the ones shown above from BPC. In the dining room I had plenums some left over so I used 3 plenums with 1 pipe going to each of them just to use them.

Thanks John, because of the run lengths from the attic to the Kitchen/utility and Dining room. The lengths are 17m to 20m from the manifolds and the transmission of air is in 75mm flexible pipes/ducting. There are many bends to get around the steelwork so I guess it would be easier to reduce the airflow rate on the plenum valves when setting up.

Hi thanks for the response, where the stairs are on the downstairs plan at the top of the plan the square box that surrounds is open to the upstairs and all the blue circles at the right hand side of the house is the supply valves so the cool air would be provided from that side.

Hi all I have a dilemma which is playing on my mind and hope you can be of some help. All bedroom doors to the landing in a home with an MVHR system often need a 10mm undercut gap at the bottom to allow for airflow between rooms. This is to ensure proper ventilation. Every bedroom has an en-suite bathroom with a door with the 10mm gap with a return extraction pipe back to the Mvhr manifold, so was thinking that the main bedroom doors to the landing might not need the 10mm gap as the airflow path would be satisfactory between the bedrooms and its own bathroom. That’s the first thing but the other thing is I am actually going to put extraction vents In the landing because of the heat that is generated in the whole house settles in this area, my thinking is it would be good to circulate that heat in the winter but also in the summer to get rid of the heat when the unit is in summer bypass mode. So because I need this extra function with the landing extraction should I put the 10mm gap on the bedroom doors to the landing because the airflow path from the bedroom can now go 2 ways to the ensuite bathrooms and the landings. Thanks in advance..