Hon&Guan 4 Inch Insulated Flexible Duct - 4 FT Noise Reducer Heavy-Duty Four Layer Protection Hose, Insulated Duct for Exhaust Fan Insulation, Heating & Cooling Ventilation, Black

Purchased for a portable AC exhaust hose replacement. Works GREAT! Gets barely warm to the touch, when the old exhaust hose was extremely hot and radiating heat back into the room. AC is a little quieter too. Can't recommend this insulated duct highly enough, I can't believe I had been undermining my AC's efficiency for years with a non-insulated exhaust duct. The duct itself feels very well-made, each end has a short length of reinforced foil which fits under the included hose clamps perfectly. Insulated outer duct begins a few inches later, and the outer duct material feels very durable and flexible. The inner duct acts as the support and the outer duct holds the insulation in place, and the result is a dramatic drop in outer duct temp. AC has been running for a few hours now the outer duct is no hotter. I think we have a winner.

The stock hoses for my portable (two-hose!) air conditioner had disintegrated, and I've long been considering buying a set of insulated hoses for it ever since I bought the unit. I'm honestly surprised that they were not insulated at all out of the box. As such, I bought two of these hoses in 6"x8'. Installing them onto the original hose adapters was a bit of a task, entailing very liberal application of duct tape. This done, I connected them up and powered the unit up. I did not buy these hoses with the intent of being quiet, but I was honestly and pleasantly surprised by how much quieter the condenser side fan was now. I can barely hear it anymore, and it quickly subsides under the sound of the compressor once pressure builds. With the original hoses, it was easily the loudest part of the entire air conditioner. I cannot measure the thermal performance directly versus the original hoses, due to the original hoses having disintegrated years ago as of me writing this review. However, I can definitely say that, before, it was actually hot behind the unit. With these, it's significantly cooler, and the unit's performance has significantly improved. It can now actually cool my garage! Something it used to struggle with. The hoses have also survived from a durability standpoint significantly better than the original plastic hoses. Although they ARE a little less convenient to store when the air conditioner's not in use thanks to their bulk. That's the only "negative", other than the admittedly improvised installation, that I can even say about them. Final Answer: If you have a portable air conditioner and use it with any regularity, upgrade it to insulated hose(s) now. You will not regret it.

Pros: Overall quality and ease of installation. Insulation is thick. Cons: The inner foil is thin, which made connecting it with the hose clamps a challenge without tearing it. This would hands down be a 5-start if the inner foil were thicker.

An absolute must for indoor free standing AC. Greatly reduces the AC noise. Does not emit heat. Very flexible and holds up well.

Excellent item, complies with requirements.

Not as described. The interior foil is perforated. The next layer is the insulation, then non perforated foil then the plastic. Says you can use it for bathroom fan with moisture laden air, which is not true. The insulation will get wet in the plastic pipe.

I purchased the 6" x 8' hose to install on my portable air conditioner. Anyone that has one, you know the heat that radiates from the included hose is very high and inefficient. Although this hose does not look the prettiest, it is an absolute must for replacing the included hose on your conditioner. Running my air conditioner prior to this hose, I could only keep the room about 8 degrees below outside temps. After installing this hose, the room cools MUCH FASTER, and also gets about another 6 degrees cooler compared to the outside. An almost double cooling efficiency. This hose is room temp to touch, and feels like it contains >90% of the heat my previous hose allowed through. In addition, the air conditioner unit runs much quieter due to the sound insulation this hose provides. At least 30% of the noise from your AC is coming from the turbulent air flow rattling around inside the hard crimps of your standard plastic hose. If you do purchase this hose for your AC, make sure to get a size slightly larger than the diameter of your input/output, so you can fix the hose to the exterior of the couplings with a good duct tape. Honestly, if you try to fix the hose to the interior, it seems like you might end up rupturing the lining and exposing the fiberglass inside, which would be bad. I used the larger size and it secures nicely in place with a good 3" wide duct tape.

I needed to remove and replace the inner aluminum duct as it was full of holes. I don’t understand how or why they would want that. I don’t want hot air from my dryer going anywhere but outside. It cost way too much for having to do that rework to it. But it has stopped the condensation issues I had.