cooling and ventilating one room in a passive build

[Technoheckno]

Hi,

I've been looking through the forums and found a lot of useful information but I still feel the need to ask a few stupid questions. I've got plans for a 'passive' design two bedroom house. Downstairs will be a single garage and a music room. The amplification and electronic equipment, as well as the other four people with whom I generally practice generates a fair bit of heat and even in a normal building tends to make it unbearably hot occasionally in the summer. Would the MHVR on it's own provide sufficient cooling and ventilation for that one room? Opening windows is not really desirable, as we get sound from outside(especially if we're recording a session). Would we require an additional form of cooling and ventilation and if so would there be one that is silent in operation?

Thanks

Al

[Conor]

Nope, not a chance the MVHR would cool. Single room aircon unit would be the ticket.

[macglo]

Hi, Agree with Conor a MVHR will not provide anywhere near sufficient cooling for your equipment

[SteamyTea]

If there are 5 if you in there, and you all generate about 300W, then that is the same as a fan heater going. 

Have you thought of playing at a slower tempo.

[Nickfromwales]

52 minutes ago, Conor said:

Nope, not a chance the MVHR would cool. Single room aircon unit would be the ticket.

+1, and a split unit not an all-in-one as you'll need to be ale to dump the waste heat to atmosphere. Also consider a drain , or path for a pumped condensate to be taken out via.

[Technoheckno]

13 minutes ago, SteamyTea said:

If there are 5 if you in there, and you all generate about 300W, then that is the same as a fan heater going. 

Have you thought of playing at a slower tempo.

 ?We're all knocking on a bit and play fairly slow anyway - I guess if we had enough fans it might make a difference though :-)

Al

[Technoheckno]

1 hour ago, Conor said:

Nope, not a chance the MVHR would cool. Single room aircon unit would be the ticket.

 

30 minutes ago, macglo said:

Hi, Agree with Conor a MVHR will not provide anywhere near sufficient cooling for your equipment

 

15 minutes ago, Nickfromwales said:

+1, and a split unit not an all-in-one as you'll need to be ale to dump the waste heat to atmosphere. Also consider a drain , or path for a pumped condensate to be taken out via.

 Thanks very much to you all. That confirms what I suspected. Anyone have any thoughts on what would be the quietest solution for single room aircon units?

Al

[Nickfromwales]

1 minute ago, Technoheckno said:

Thanks very much to you all. That confirms what I suspected. Anyone have any thoughts on what would be the quietest solution for single room aircon units?

Al

Don't buy cheap  

Check manufacturers details for comparisons on operating dB levels @1m

Edited October 25, 2020 by Nickfromwales

[PeterW]

Does the music room have to be part of the main structure ..? Or could it be isolated and treated as a different build with say less insulation ..? More than the garage but less than the house ..??

[SteamyTea]

Can you put all the electronic stuff in a ventilated area, then pump the excess heat out. 

Or go capella. 

Being someone that 'speaks' BSL, hours of fun can be had singing in a public library.

Edited October 25, 2020 by SteamyTea

[Technoheckno]

1 hour ago, Nickfromwales said:

Don't buy cheap  

Check manufacturers details for comparisons on operating dB levels @1m

 

1 hour ago, PeterW said:

Does the music room have to be part of the main structure ..? Or could it be isolated and treated as a different build with say less insulation ..? More than the garage but less than the house ..??

 

1 hour ago, SteamyTea said:

Can you put all the electronic stuff in a ventilated area, then pump the excess heat out. 

Or go capella. 

Being someone that 'speaks' BSL, hours of fun can be had singing in a public library.

Thanks again,

I'll research units and db levels. The room does need to be part of the main structure and it's probably best to treat it as the rest of the build, as, while I want it as a music room at the moment, once the arthritis stops me playing altogether it may have to be repurposed to a more traditional function.

Al

[Nickfromwales]

If going to the grief of fitting a split AC with an external unit, why not have a think about putting a second fan-coil unit on the landing / bedroom 1 for additional household cooling? The external unit can be sized to accommodate more than one internal unit, so maybe two, or three, birds with one stone. Maybe also consider an f-gassed duct cooler fed from the same external unit to lower ( or raise ) the incoming air temp via the MVHR. Might as well consider squeezing a one-trick pony for a few more tricks if not too costly.  

[AliG]

We have a cinema room with a rack of equipment and a projector in it.

 

The heating has never been on in this room no matter how cold it has been outside.

 

With a few people in the room watching a movie the temperature can easily get up to 27/28C.

 

I knew it would be hot so had them make the MVHR an extract to move the heat around, but it doesn't't make any difference.

 

What does make a difference is simply leaving the door open into the hall, but it is a vastly larger area.

 

The AV cabinet is also open at the back to the utility room which is connected to the garage. In  the summer I leave the door open into the utility and that really helps.

 

If you are creative about it, you could try to use the waste heat to heat the rest of the house depending on the position of the equipment. Try to ventilate it to a colder area or an area that will need heated.

[Technoheckno]

3 hours ago, Nickfromwales said:

If going to the grief of fitting a split AC with an external unit, why not have a think about putting a second fan-coil unit on the landing / bedroom 1 for additional household cooling? The external unit can be sized to accommodate more than one internal unit, so maybe two, or three, birds with one stone. Maybe also consider an f-gassed duct cooler fed from the same external unit to lower ( or raise ) the incoming air temp via the MVHR. Might as well consider squeezing a one-trick pony for a few more tricks if not too costly.  

That idea had had occurred to me , or at least the part about using it to feed more than one room. I hadn't thought about duct cooling. At the moment I'm just looking at ideas and trying to get an idea of prices so thanks again.

1 hour ago, AliG said:

We have a cinema room with a rack of equipment and a projector in it.

 

The heating has never been on in this room no matter how cold it has been outside.

 

With a few people in the room watching a movie the temperature can easily get up to 27/28C.

 

I knew it would be hot so had them make the MVHR an extract to move the heat around, but it doesn't't make any difference.

 

What does make a difference is simply leaving the door open into the hall, but it is a vastly larger area.

 

The AV cabinet is also open at the back to the utility room which is connected to the garage. In  the summer I leave the door open into the utility and that really helps.

 

If you are creative about it, you could try to use the waste heat to heat the rest of the house depending on the position of the equipment. Try to ventilate it to a colder area or an area that will need heated.

Thanks for that. Originally I assumed that the purpose of an MHVR unit was to do all of this but from what everyone seems to be saying it sounds as though they don't cope efficiently enough with extreme differences between different locations within the building - a costly shame :-(

 

[AliG]

15 minutes ago, Technoheckno said:

Thanks for that. Originally I assumed that the purpose of an MHVR unit was to do all of this but from what everyone seems to be saying it sounds as though they don't cope efficiently enough with extreme differences between different locations within the building - a costly shame ?

 

MVHR is just a better way of ventilating a house without heat loss, it doesn't move enough air to change the temperature of rooms.

[Technoheckno]

49 minutes ago, AliG said:

 

MVHR is just a better way of ventilating a house without heat loss, it doesn't move enough air to change the temperature of rooms.

I understand that now.

[SteamyTea]

It is all to do with the low specific heat capacity of air.

Air is around 1 kJ/kg.K.  In more understandable units, that is 0.00027777777777778 kWh/kg.°C

So if you have a system that is drawing 500W (a small fan heater) and it runs for 1 hour, that is 0.5 kWh or 1800 kJ.

Now a kg of air has a volume of around 0.83 m³.

So to keep the air at the same temperature (assuming no other losses), you have to shift that air away at a rate of 1500 m³/hour.

It is more usual to use the litre/second as a unit, so that is 417 litres/second.  Quite a lot.

 

[Technoheckno]

13 hours ago, SteamyTea said:

It is all to do with the low specific heat capacity of air.

Air is around 1 kJ/kg.K.  In more understandable units, that is 0.00027777777777778 kWh/kg.°C

So if you have a system that is drawing 500W (a small fan heater) and it runs for 1 hour, that is 0.5 kWh or 1800 kJ.

Now a kg of air has a volume of around 0.83 m³.

So to keep the air at the same temperature (assuming no other losses), you have to shift that air away at a rate of 1500 m³/hour.

It is more usual to use the litre/second as a unit, so that is 417 litres/second.  Quite a lot.

 

Sounds as though we might have to practice in a wind tunnel :-) But, more seriously, I   do think I understand 

[SteamyTea]

1 hour ago, Technoheckno said:

Sounds as though we might have to practice in a wind tunnel :-) But, more seriously, I   do think I understand 

Well you have a lot more than 1kg of air to get rid of, but that also means it does not get so hot.

But if you do fit a very large fan, and grow mullets, you can make so old school video. 

The only people that say they don't understand today's music, are the ones that don't get it.

I don't get it.

[Technoheckno]

1 hour ago, SteamyTea said:

The only people that say they don't understand today's music, are the ones that don't get it.

I don't get it.

I don't get it either. My pal, a retired professional trumpet player has joined this https://pipedown.org.uk/ 

[SteamyTea]

Not got zoom, but I know it goes on mute quite often.

 

I shared a flat with a Kiwi Sax player. I had to move out.

Though he did do a good version of Bowie/Mercury Under Pressure.

[Technoheckno]

1 hour ago, SteamyTea said:

Not got zoom, but I know it goes on mute quite often.

 

I shared a flat with a Kiwi Sax player. I had to move out.

Though he did do a good version of Bowie/Mercury Under Pressure.

My pal tells the story about how, in the old days, there always used to be an advert in the music press along the lines of "Join the band of the Grenadier Guards and learn to play a musical instrument ....or the saxophone" :-)