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Community and Q&A

Insulating Comfotube

daniel661 | Posted in General Questions on

I’m installing a standalone ERV system in an unconditioned attic and want to utilize the Zhender comfotubes for ease of installation and commissioning the system to ensure each room is receiving the appropriate air flow, but Zhender recommends the tube be installed in a conditioned space.  

Would there be any issue with running the comfotube thru an r8 4″ inch flexible duct?  

I live in climate zone 3 in the USA and freezing is not an issue.

My thought is that the insulation would help with heat transfer.  

Any input is appreciated

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  1. user-2310254 | | #1

    It's my understanding that the Comfotubes are the most expensive part of the Zhender system. One online listing had 12 foot x 3 inch coil of tubing for $329. The same length of metal duct is about $10.

    Out of curiosity, which brand/model ERV are you installing?

  2. qofmiwok | | #2

    It's a lot but not that bad! I paid $114 per 50 feet. This is for ComfoFlex, which they are selling now instead of ComfoTube. My ComfoFlex is installed but not my larger insulated piping yet (ComfoPipe). This is much more, $29/meter plus elbows. They actually don't have this in stock in the US right now so I've considered using metal rather than delaying. But cutting metal seems a whole notch more difficult, so we'd probably have to have the HVAC guys do it which would cost more than paying for the Pipe.

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