# Forum Home Renovation Heating & Cooling  Central Heating - Location of Return

## statov

I need some advice.  We are installing a Braemar (TH320) 7 point gas ducted heating into our house, (ceiling vents) and were told by the installer that it's ok to put the return vent in the ceiling as well.  The house is approx 23 squares. 
Initially we were considering putting the return vent into a linen cupbaord in the hallway, but were told this would be a bad idea as half of the cupboard would be lost.  The installer told us that if we put it in the ceiling it would not affect the heating of the home as the heater unit would be able to cope, due to the small number of vents and size of home. 
Does this sound right? 
I'm concerned as someone told me that you should never put return vents in the ceiling. 
Appreciate any help of advice.

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## president_ltd

historically returns were done in the ceiling - but i'd hardly call it optimal.
for one thing, heat rises. you're better off getting "return air" at ground level (cooler air). 
putting a return in a linen closet does not necessarily result in "half the closet lost".
for us, it amounted to a "hat" type arrangement on the ground (sort of like a top hat on the floor, but with meshing to allow the air to go through), and a grille in the wall alongside the adjacent wall, but e.g. the first shelf in the linen closet is perhaps 450mm height off the ground, the grill is about a 800x500mm, its just that floor level that has been lost, even then just part of it, not all of it. 
benefits of return air in linen closet is that whatever is in there gets 'aired' too. 
are there any other factors for placement?  e.g. linen closet is too far away, return air ducts would be a lot longer, placement of heating unit would mean extra electrical/gas work, etc?

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## droog

Hi Statov 
First of all I am not in the heating and cooling industry only speaking from my own experience. 
I designed our current Braemar TG series central heating, a design guide from Braemar had a section on return air: 
5 RETURN AIR
5.1 Return air grille location
The following points are important when selecting a location for the return air grille:
 Always locate in a suitably heated central area, eg, central hallways.
 In a zoned system, the return air grille must be located in the common zone.
 Do not locate in a bathroom or laundry as moisture present in these rooms may settle on the fan/heat exchanger when the heater is not in use.
 The return air grille must have a clear reurn air path from all outlets and must not be
obstructed, eg, by carpets, furniture, clothing, open doors etc.
 It is recommended that the return air grille be located at a low level to ensure effective heated air distribution. If a high level return air grille is used cold spots at floor level may result, and system performance and efficiency will be reduced.
 Air should not be drawn through un-heated areas. 
Our house being period style 3m ceilings and in a cold environment I had not factored in the need to ensure that heated air is drawn into the return air, without this the fan speed can "hunt" from the preset speed trying to maintain a suitable outlet temperature. This would not be such a factor in lower ceilings or more temperate zones but has created some issues for me, ideally I would locate the return higher up the wall if I had to do it again. 
My folks in melbourne have had a Braemar TH series installed and the return is in the ceiling and they have no issues with regard to its location. 
Any reasonable installation company should stand by its installation practices and address any issues with the operation of the central heating after installation. Check what the warranty conditions are for your installer.  
Regards Dave

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## Bloss

Droog makes sense, but as president_ltd says linen cupboard works fine too. Main thing is to have the right size vent in the cupboard door. Warning though - if you can clothes or other items in that cupboard the will collect lint and fluff and dust as the air circulates and you'd be amazed how much. Harmless enough, but does need regular vacuuming.

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## statov

Thanks for the posts guys.  Has really helped me heaps. I have decided I will place the return vent in the ceiling, as the ceiling height is relatively low within the house, approx 2.3mtrs, so it should be ok.  It will be within the hallway, so by the looks of things this is a plus as well.  And best of all I get to retain the linen cupboard  :Biggrin:

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## Uncle Bob

> And best of all I get to retain the linen cupboard

  You still can. Place the return duct in the ceiling of the linen cupboard and put a door grill in the bottom of the cupboard door.

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## Bloss

> You still can. Place the return duct in the ceiling of the linen cupboard and put a door grill in the bottom of the cupboard door.

  Is there an echo in here?   :Biggrin:

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## GraemeCook

Whilst it is more efficient to have the return air vents low down, the vast majority of heated commercial buildings have the supply and return vents in the ceiling.  Location, air flow rates and air volume rates are just part of the design engineering. 
I'd be wary about placing vents in a laundry cupboard as the contents must surely impede airflow and effectiveness. 
Cheers 
Graeme

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## Timmo

> Whilst it is more efficient to have the return air vents low down, the vast majority of heated commercial buildings have the supply and return vents in the ceiling.  Location, air flow rates and air volume rates are just part of the design engineering. 
> I'd be wary about placing vents in a laundry cupboard as the contents must surely impede airflow and effectiveness. 
> Cheers 
> Graeme

  And you'll end up with very dusty linen.

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## Bloss

> Whilst it is more efficient to have the return air vents low down, the vast majority of heated commercial buildings have the supply and return vents in the ceiling.  Location, air flow rates and air volume rates are just part of the design engineering. 
> I'd be wary about placing vents in a laundry cupboard as the contents must surely impede airflow and effectiveness. 
> Cheers 
> Graeme

  Commercial buildings do that as there is usually no floor plenum and the cost to have one is too high - so they compromise. This is also offset because commercial A/C and heating systems are generally operating at much higher efficiencies too (scaling up in this case gains great improvement). In most residential houses there is underfloor access so one should choose the most efficient solution - heat from underneath, cool from above. 
The cupboards is a linen cupboard not laundry and this is very common and highly effective - the intake hat is usually about 300-400mm in diameter and  intrudes above the floor around 200mm or so. The main issue is to ensure that the vent in the bottom of the cupboard door is sufficiently large to allow full volume airflow. The contents do not impede as they are above any airflow not in its path.The only downside is what I said above - the floor vent has to be kept clear and there can be some dust at the lower levels as the air flows through. For most linen cupboards the impact is a loss of the lowest shelf and often just the floor space below the lowest shelf - and the appearance of the vent in the door. 
Just as the best place for the unit is centred on the house (if it can be) so it is for the air intake - and linen cupboards are often in halls (so good flow from other areas of the house and near the centre. Interestingly with all central systems people often forget that they need to think through what happens when doors are closed. Especially in a  single zoned system it is often the case that there is insufficient under-door gap to allow good airflow - in commercial building they put vents in the doors - in residential use this is often a cause of uneven heating or cooling. 
As Graeme says the good design should cover this - too often it is neither good design nor good installation.

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