How to improve ducted air conditioning?

[Wai2021]

Hi all,

I’m having problems keeping cool at night, especially when it’s been very hot of late and believe my AC hasn’t been setup optimally. Our master bedroom is directly west facing and temps get to about 30 by the late afternoon on a hot day and the heat does not dissipate overnight, forcing us to turn on the AC. I live 4yo duplex that was built with a ducted AC system split across 3 zones as follows:

1. Downstairs living area/open kitchen

2. Upstairs hallway, Master and 2 Bedrooms

3. 4th bedroom

When they installed the AC they configured the 4th bedroom (directly north facing) as a zone on its own upstairs when I think it really should’ve been our Master Bedroom.

So due to this ducted zones setup I can’t cool individual rooms such as the Master Bedroom that desperately needs it, and I’m forced to turn on the AC across all rooms upstairs.

The problem is then all the other bedrooms upstairs freeze overnight and drop to like 18C when the master bedroom is only being cooled to around 22C. As such we are also forced to keep the bedroom doors opened overnight so they don’t get too cold, but this is not ideal due to privacy etc…

Would getting someone to rezone our upstairs AC simply fix the problem I have? Ie. swap the duct to make our master bedroom on a zone of its own?

Or must I look into some more drastic ceiling cooling solution along with this?

thank you

[EricL]

Hi @Wai2021

I'm sorry to hear that your ducted aircon is not ideally set up. There are several things you'll need to get before you try my recommendation. First, you'll need to identify the make and model of your aircon system. Second, are they still in business and do they still service aircon units? Third, always ask for a quote by email so that you can compare it to other installers. 

The easiest way to isolate the master bedroom is to install a bypass controller in your ducted system. This bypass will shut off the other rooms and concentrate the cold air only in the master bedroom. Your aircon specialist might even suggest installing a booster fan so that the air is pushed further along. 

There are more expensive methods, but using a bypass controller would be the most cost-effective as you will not have to relay your ducting. My number one tip for your project is to make sure you get at least 3 quotes and make sure that they itemize all the work they will perform, what they will provide, and an explanation of how the new system will operate.

I've placed an image below of a ducted bypass to give you an idea of how the other rooms will be shut down and only your room will get all the cold air. Sounds like a very interesting project, any updates you can provide would be much appreciated.

If you need further assistance, please let us know.

Eric