HVAC DUCTING AND SUPPLY PLACEMENT

3 years ago

Hi? i am building a house. two story. i am using two heat pump and two air handler.

is okay and functional to have all the supply and return vent on the ceiling of the second floor and on the first floor all the supply on the floor and the return on the bottom of a wall. the mid floor will be completely insulated with Blow-In-Blanket system

please share your thought. pro and cons of this setup?

i will like to know if it is okay to use i joist bay as a return plenum. the same bay has electrical and low voltage wire running through it.

is it okay if i cannot bring the duct down to the air handler return box and use the air handler closet with a door as a return plenum to get the air from the return duct terminating on ceiling of the closet.

thank you

Comments (7)

raz kamz
Original Author
3 years ago
last modified: 3 years ago
thank you for sharing
Seabornman
3 years ago
Don't put ductwork in attic. I don't believe it's legal for non-rated electrical wire to be located in any ductwork. If there's a fire, it's possible to spread noxious smoke through the space.
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raz kamz
Original Author
3 years ago
hi please i looking for more wisdom and idea.
mike_home
3 years ago
You should not use a joist bay as part of the return. It is probably not allowed by code in your area, Even if it was, it is a terrible idea. All the dirt that accumulates in the joist bay will be pulled into the filter, or worse into the air handler if the filter is on the return intake.

If you have to install duct work in the attic then use R8 duct work with additional insulation on top and around it. There is no issue with having supplies on the bottom of a wall if the ceilings or 8 or 9 feet high. The returns should be near the ceiling.
raz kamz
Original Author
3 years ago
thank you for the knowledge
Bruce in Northern Virginia
3 years ago
It would helpful to know your location and climate.

Its fairly common in warm Southern climates to have supply vents in the ceiling, since good A/C is the priority and the A/C unit itself may be in the attic. However, in a Northern climate they usually put supply vents close to the floor and under the windows (biggest source of cold air) because that seems to work better to deliver heat.

If you design your attic as conditioned space, with the foam insulation on the underside of the roof deck instead of the attic floor, you will have the option to use uninsulated ductwork in the attic. This type of insulation is becoming more common as an alternative to a vented attic.

Bruce
Mini-Split Warehouse
3 years ago
The Benefits of a Duct System Analysis.

https://www.air-conditioning-ductless.com/

A duct system analysis provides you with a professional assessment of the condition of your ductwork. This invaluable service has a number of important benefits, including:

Cost savings. Reduce the cost of energy in your home as all your conditioned air reaches your living space, and heating and cooling equipment runs at optimal performance.

Increased comfort. Experience even temperatures throughout your home, and increased airflow.

Improved health. Those who suffer from allergies or asthma will benefit from the enhanced air quality.

Prolonged lifespan of HVAC equipment. Clean, well maintained ducts circulate clean air through your home, preventing undue wear and tear on system components due to dust or other particulates.

HVAC DUCTING AND SUPPLY PLACEMENT

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HVAC DUCTING AND SUPPLY PLACEMENT

Comments (7)

raz kamzOriginal Author

Seabornman

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