TimCx

Ah I did see mention of a spreadsheet but I didn't find it. Any links would be appreciated.

Hello all, I have read many of the threads in this forum but I still have a couple of questions ! I am having to replace my MVHR central unit as it has failed. The house has a floor area of about 250m2 on 2 floors but is slightly unusual in that the living space is upstairs and the bedrooms etc are downstairs. The house is 11 years old and very well insulated but not passive. I will not be replacing the ducting just the central unit. The MVHR unit currently installed was manufactured by a company called 'Ventalutior' but they ceased trading some time ago, I have very little information about the unit but it seems very small its 560 wide*500 tall*260 deep (mm) I have no flow rate information at all. The whole system was commissioned and signed off in 2011. Upstairs the house has: kitchen, lounge/diner, study, hallway and utility room (with extract vent) and 2 toilets. The kitchen has extract vent and also a separate cooker hood that is not connected to the MVHR system. And downstairs: 5 bedrooms (1 with E/S) 2 separate bathrooms (one is shower only) a hallway and a plant room (which has an extract vent as we use it for drying clothes). I am confused is sizing the replacement unit, going by the floor area and the required rates for the number of rooms I think I need a very large unit but the existing one is small. Maybe the regulations have changed a lot since 2011? I have a few questions that I would appreciate some help with: 1) What size unit should I be looking at and how do I calculate this? I have seen the building regs but I am confused by the 0.3ls required for each m2 against the room rates, are there any tools that can help with this? 2) Can you recommend any good quality manufacturers for the replacement unit, Mitsubishi Lossnay and Vent Axia have been mentioned by a friend. 3) Is it worth paying to get a unit with humidity sensors and do they negate the need for boost switches (as in current system) for the bathrooms and utility room. 4) Are there any 'must haves' for MVHR systems, the current unit has nothing but I would like to be able to monitor the new one on my computer if possible but this is not essential. Thanks in advance

Hi All just joined, we have been living in well insulated modern house for about 10 years now, interested in all sorts of alternative energy and energy efficiency. Specifically joined the site after a longing period of guest browsing, as I want to find some information about MVHR systems as ours has broken and will have to be replaced.