Ducted air-con, why can't I close my glass sliding doors?

I've got ducted air con through-out the house. House is about 15 year old and has a security-grill in ceiling so that you don't need to have a door or window open. Even if I turn the air con down to 50% fan and a window open in another room, internal door shut, I can't close the glass sliding door. My dogs can open screen doors so with the kids I get them to close the glass doors so they are constantly being used. Is this a normal problem with glass sliding doors and ducted air-con?
 
Not quite sure I get this..... Are we:

1. talking about a door that can;t be closed due to air pressure? Or some other technicality?

2. talking about an evap cooler? Our refrigerant ducted cooler works best with all doors/windows shut...

The Y-man
 
I would say it was down to air pressure. We find we have to have a window or sliding door open in each room otherwise doors slam and windows whistle.
 
Ducted rc/ac requires a circulation of air back to the inlet. Each room will have a ceiling outlet and air needs to return to the inlet (usually in the ceiling with filter close to control).

Sliding doors generally seal better than normal doors with "gap" underneath, so you either need to keep sliding door slightly ajar when "zoning" a/c to this room, otherwise fit a vent to the door to allow air to re-circulate when door is closed.
 
http://www.breezair.com.au/faq.html

Above is the system I am talking about.

I get what you are saying Joe D, but it's not what I'm asking. Sorry all of above, I worded it badly.

My issue isn't with air being circulated in rooms without vents, rather that I can't close my doors and windows in the house. ie i have to turn air-con off to be able to do it as their is a suction/pressure thing happening, and constant repair needed for particulary the sliding doors - they are constantly lifted off their tracks. Because of the issues I started using a window instead and that started to come off track also. :confused:
 
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:) I get it now, by me closing interior door it made it harder to close exterior door due to extra airflow. (What Joe D was saying). I'll try having two windows open in main area next time and see if that helps.
 
I've got ducted air con through-out the house. House is about 15 year old and has a security-grill in ceiling so that you don't need to have a door or window open.

This grill in the ceiling seems to be having no use ,
This air con has to suck its air from somewhere.
In your eve sheets outside there must be vents or whirly birds on the roof.
It is possible that you need to put more vents in the exterior eve sheets.;)
 
I have ducted air con and I have an air return grill in each isolation switch area so that the air coming from the AC is the same as the amount of being returned to the AC.

My brother also has Ducted AC and he has no problems with doors windows etc except that it is more efficient if all external windows and doors are closed when in operation.

Perhaps the unit is too big for the house and should be run on a lower fan speed ?

There needs to be a balance in the cycle of air, perhaps it is not installed correctly or it needs more return air vents.

I don't think you should have to do all the things you are doing, we don't do any of that stuff.
 
Me again :)

Perhaps that security grill in the ceiling is actually a return air vent with a blocked filter.

Have you cleaned all of the return air vent filters recently, could be worth a try.

We both have two return air vents with filters that need to be cleaned at least every six months if the AC is on a lot.

Have a look there first HTH
 
Read the link. It's an evapourative system. Not refrigerative. It's all about air flow - evap sucks air in from outside, evapourates some water which sucks the heat out of the air, then pushes it via ducting into the room. It then needs to get out - if the door is shut you need a window open, with the door open you will still need a window open somewhere.

A refrigerative unit recirculates the same air - sucks it in from the room (via a central point), cools it down, blows it back out via the ducts into each room.
 
This grill in the ceiling seems to be having no use ,
This air con has to suck its air from somewhere.
In your eve sheets outside there must be vents or whirly birds on the roof.
It is possible that you need to put more vents in the exterior eve sheets.;)

Yep, there's two whirlybirds

I have ducted air con and I have an air return grill in each isolation switch area so that the air coming from the AC is the same as the amount of being returned to the AC.

My brother also has Ducted AC and he has no problems with doors windows etc except that it is more efficient if all external windows and doors are closed when in operation.

Perhaps the unit is too big for the house and should be run on a lower fan speed ?

There needs to be a balance in the cycle of air, perhaps it is not installed correctly or it needs more return air vents.

I don't think you should have to do all the things you are doing, we don't do any of that stuff.

Me again :)

Perhaps that security grill in the ceiling is actually a return air vent with a blocked filter.

Have you cleaned all of the return air vent filters recently, could be worth a try.

We both have two return air vents with filters that need to be cleaned at least every six months if the AC is on a lot.

Have a look there first HTH

I'll investigate the return air vent further. At a quick glance it looks as though a stirophom sheet has been screwed onto a beam down the middle of vent. Either side of beam has a stirophom flap. When i turn the air on the flaps lifts about 45deg if I have a window completely open. If I have the window half open they lift to about 30 degrees. With all windows shut the flaps are open 90 degrees. Theres was also some silver thick (reflective?) alfoil type stuff covering a bit of the flap so I'v moved it away from vent.
There are no filters.

Are all homes automatically fitted with return air vent when you have ducted air con installed?

With the fan speed on 39 I can open and shut a different window to the one i have left open Ok, but when i turn it onto 100 it's difficult still. With no windows open it's hard to shut my laundry door that doesn't have any airconditioning vents.

Maybe I'm not doing this properly also:

5. How should I use my evaporative air conditioner to get the best results?

To provide effective cooling, evaporative air conditioners need to be able to create airflow through the home, exhausting hot air outside. To assist the cool fresh airflow through the home, open windows and outside doors that are furthest from the outlet vent. In the rooms that have vents you should provide an opening to outside that is approximately twice the opening area of the vent.


Being an open plan house maybe I should be leaving kitchen window open double the size of the vent in dining area plus the lounge area.

Will see if I can find more info on my air-con system. Thanks everyone!
 
There needs to be a balance in the cycle of air, perhaps it is not installed correctly or it needs more return air vents.

I don't think you should have to do all the things you are doing, we don't do any of that stuff.

It does sound like we need another return air vent to stop the air pressure/door and window problems.

Thanks again.
 
Hi,

It would seem that yours is different to ours, but the concept of equal air pressure would still have an effect.

As you have whirly birds on the roof, you could put vents/grills through the ceiling into the roof cavity. As we know hot air rises so this would allow the air pressure created by the air cooler to force the higher warmer air up into the roof cavity. The whirly birds then would spin faster as the air is forced out, maybe even more whirly birds in the roof if necessary.

Worth thinking about and not that expensive to improve, meanwhile I guess you turn the fan down once the place has cooled off a bit.

Merry Christmas
 
Just have some more open windows! A 'return vent' is for a reverse cycle refrigerative system - which is essentially a closed loop. This is evapourative. You don't need any 'return air vents'. Diverting it into the roof cavity won't really work - out one hole in the ceiling and up another?? Even with whirlybirds or whatever, you'll still be pressurising the roof cavity.

Evapourative systems usually have larger duct vents into the room which are positioned well away from the windows, so the air 'flows' across the room and out the window.
 
Hi Apoc,

Yes, as we went along it became apparent they are different systems, but air pressure equalisation is still the problem.

I agree that simply opening windows will solve it, I guess turning down the fan will help as well but INV is looking for alternatives to having windows open all the time (as I understand it).

The coolers sure must pump out some air !!
 
My biggest issue is doors and windows are getting sucked off their tracks, runners, locking mechanisms are getting ruined.

In brochures it states cool breeze offers a security Relief vent which allows cool air in the home to be vented up into the ceiling cavity to continue it's cooling task......................This is particlary useful for at night times when security requires doors and windows to be closed.

* Operate system with windows and doors shut
* Increased cooling capacity


One of the problems is though that it's really difficult to shut windows and doors while system is turned on and especially when you're locking up for bed. I'm pretty sure even when I turn system fan down to "one", and have one window open, the doors lift off the tracks while I'm trying to shut them and locking mechanisms don't match up unless slamed.

I guess the best thing to do is play with it more and make some notes of what it does with different settings and different windows and doors.
 
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