Single room MVHR with summer bypass - on a small budget?

[Starmax]

Hello all,

 

I am looking for advice on the following. I am in the UK and have a detached house, built in 1998. I have converted one of the upstairs bedrooms into a home cinema. The room is 4.5m x 2.5m (not as big as I wanted) with a built in cupboard and also an alcove. I will be installing a cassette blackout blind for the window. So I don't annoy the neighbours with sound leakage, I shut the window when using the room. As you can imagine, in the recent warm weather, the room gets quite warm especially with the projector blowing out hot air. I've been looking at installing a ventilation system to help maintain a constant temperature and keep the air fresh. At first I got quite excited by the idea of an MVHR system as this would help keep the room warmer in the colder months.

 

I looked at single room MVHR systems, namely Vent-Axia and Blauberg. My budget would stretch to these. Then with some more research I realised I need a summer bypass system in order to keep me cool in the warm weather. Neither the Vent-Axia HR100R or Blauberg Ultra D105-A have a summer bypass option.

 

I don't wish to have a wall mounted system, I have seen these types available. What I would like is just an intake and extract valve fitted within the ceiling.

 

Does anyone know if there is such an MVHR system with summer bypass within a £250 budget?

 

Otherwise, my plan B is to install the valves and then intake fresh air and extract stale air using ducting and inline fans. If this is my only option then is there such a thing as a filter box that I can use on the intake side of things that uses replaceable filters? I've seen that Blauberg do a CleanBox system that looks great, but is over my budget. Anything similar to that? I'm happy to DIY to a certain extent. I was thinking of using a pollen filter and housing from a car as a last resort unless someone does something for this type of situation. 

 

The other thing was the control of the inline fans. It would be good to remotely control them and to have speed control - so I can trickle vent during the winter and then go full speed in the warm weather. Is this possible with a limited budget? I have updated the extractor fans in my bathroom and en-suite and connected these via smart plugs so I can voice control their operation. I can see me doing the same for the cinema room, but this won't give me speed control. I'd welcome any thoughts and suggestions on what others have done to achieve the same goal?

 

Thanks!

 

[MJNewton]

I think you might be expecting too much from MVHR - particularly a single room one - in terms of their ability to cool (or heat) a room. With the limited heat capacity of air coupled with the relatively slow flow rates that's not their raison d'être. View them more for their cost-effective air freshening and dehumidifying qualities and you can't go far wrong. Don't get me wrong; MVHR can really help keep a closed-up room/house fresh and in some circumstances they can have a slight active cooling effect (ironically when the summer bypass isn't active and the outside air is warmer than inside) and we do feel what could well be a psychological cooling effect from ours with that constant flow of 'fresh' air, particularly on warm still summer evenings/nights.

 

To summarise: MVHR isn't the same as air conditioning, if that's more what you're after?

Edited June 8, 2020 by MJNewton

[Archer]

I installed a Vent-Axia HR100R in a bedroom that was suffering from condensation and mould in the winter. It worked wonders and was quiet enough to run at night with the windows shut. Would recommend for that sort of use. I can't comment on models with a summer bypass, but as above it's not really the same as active cooling. They work slowly and continuously so no substitute for opening windows. You can get acoustic wall vents but I imagine that would be expense.

[Starmax]

22 hours ago, MJNewton said:

I think you might be expecting too much from MVHR - particularly a single room one - in terms of their ability to cool (or heat) a room. With the limited heat capacity of air coupled with the relatively slow flow rates that's not their raison d'être. View them more for their cost-effective air freshening and dehumidifying qualities and you can't go far wrong. Don't get me wrong; MVHR can really help keep a closed-up room/house fresh and in some circumstances they can have a slight active cooling effect (ironically when the summer bypass isn't active and the outside air is warmer than inside) and we do feel what could well be a psychological cooling effect from ours with that constant flow of 'fresh' air, particularly on warm still summer evenings/nights.

 

To summarise: MVHR isn't the same as air conditioning, if that's more what you're after?

 

21 hours ago, Archer said:

I installed a Vent-Axia HR100R in a bedroom that was suffering from condensation and mould in the winter. It worked wonders and was quiet enough to run at night with the windows shut. Would recommend for that sort of use. I can't comment on models with a summer bypass, but as above it's not really the same as active cooling. They work slowly and continuously so no substitute for opening windows. You can get acoustic wall vents but I imagine that would be expense.

 

Thank you both for your replies.

 

In case I wasn't clear in my original post, what I am wishing to achieve is a constant extraction of warm air from my room in the summer and replaced with fresh filtered air from the outside. I'd love a temperature controlled system in the summer months that I could get with air conditioning but I know that is going to be expensive. I'd hope that the constant air flow from the extraction and intake idea will be cooling enough for me.

 

In colder weather I'm wanting a slight intake of fresh filtered air from outside and probably no extraction. I'd just let the positive input ventilation effect push the stale air out of trickle window vents around the house. 

 

By the sounds of it I think the heat recovery system is not going to work for me and I'm just going to go with inline fans for extraction and intake. I'll post in the non-MVHR section for ideas on what I can use to achieve this.

 

Cheers!