Heat and AC ducting question.

[ben2go]

Does your heat and AC systems use the same ducting? If so, are there dampeners or someway to stop back feeding the system that is not in use? My concern when using heat or AC is loosing air through the system that is not in use. My idea is to build or have built a plenum that allows me to block air flow to the system not in use. Something similar to a dust collection blast gate.


https://www.amazon.com/POWERTEC-701...9db1dd2dadbfbe71a00a2d065a03e2&language=en_US

 

[bayview]

Is there really a problem?

 

[healhustler]

Hmmm. I guess you must be talking about non-integrated heat & A/C systems piped into the same ducting. Yeah, I guess there could be some loss from system back pressure of heat into A/C units and A/C into furnaces, etc.. Perhaps just a standard 45 degree in-line junction damper where the heat enters the ducting. By simply switching the lever, it would open one while simultaneously closing the other, or, install a backdraft damper in the line of each of the A/C and heat sources like pictured. If you do rectangular ducting, use a vent hood backdraft unit.

 

[ben2go]

Is there really a problem?

I see where the air can go towards the system that is shut down instead of out through the intended vents. My system will use diesel forced air heaters and basic water cooled marine AC systems utilizing the same ducting.

Hmmm. I guess you must be talking about non-integrated heat & A/C systems piped into the same ducting. Yeah, I guess there could be some loss from system back pressure of heat into A/C units and A/C into furnaces, etc.. Perhaps just a standard 45 degree in-line junction damper where the heat enters the ducting. By simply switching the lever, it would open one while simultaneously closing the other, or, install a backdraft damper in the line of each of the A/C and heat sources like pictured. If you do rectangular ducting, use a vent hood backdraft unit.

You're right on track, separate heat and AC systems. I want both systems to be as efficient as possible.



Thanks. Your ideas make more sense than blast gates all though all mentioned would work. The dampeners would require the least amount of room to operate. The ducts will be round, insulated, and sized according to the systems requirements.