To Daikin DZK or not
罗伯•罗斯| Posted inGBA Pro Helpon
It would be nice to have zones using a single indoor air handler. But my gut tells me that this DZK thing would cause way more friction loss and in the end would be less energy efficient.
Thoughts?
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Replies
Do a good job of duct design and efficiency impact will be low. But only you can put a value on increased comfort.
Theses systems can certainly be made to work and can be reasonably efficient. It likely won't be as efficient as a couple 1:1 systems. The lower the load of a home, the less zoning is an issue generally. Good modulation also takes care of a lot of comfort issues.
One of the bigger problems will be that I think the smallest unit is 3 tons. Daikin equipment is also expensive.
See here for more discussion://m.etiketa4.com/question/difficulty-finding-a-modulating-multi-zone-air-source-heat-pump
I am designing a fujitsu slim duct system and considering implementing a VAV of some sort to drop the temp of my little used conditioned attic space. It will be a slave with no ability to call for heat. This should work reasonably well as the space has a notably lower heat loss to volume ratio than the 2nd floor space served by the system. The biggest reason for doing this to stretch the cold weather capacity a bit further for short periods. It may yield some energy use benefits, but I will only push that so far due to moisture concerns. I still have some numbers to crunch to see if it will work and make sense. It will be a bit of a science experiment.