Connecting “Flex Duct†to a heater

[lahabra]

I am planning a new heater install, I want to use Flex-Duct for the supply air and for the Return air.

I am concerned that the hot air could melt or burn the plastic hose if it is too close to the burner.


1. Can I connect Flex Duct directly to the a heater?

 

[Jadnashua]

I don't think so. There are some metal flexible ducts, but rigid ones probably work better. I do not know what the codes say. The additional turbulance and friction will slow the air down, too, and give any dust a good hiding place to build up.

 

[Sponsor]

 

[Nubbin]

duct

some codes/install instructions require the flex duct to be kept 4 inches away from ANYTHING that reaches 250 degrees F. The outlet of a gas furnace is often limited to 160-180. However, a short plenmum will move the duct(s) further away from the radiant heat of a heater and improve air flow and reduce a chance of causeing hot spots in your heater that would void your warrant.