I can think of a couple problems with your existing fan. 1. Flex ducting has a very high friction loss (resistance to flow) so when using flex duct it is best to oversize it at least one nominal trade size. (personally, I ry to avoid using flex duct) 2.Check you fan unit. Nearly all of them have a small metal flapper door on the discharge port that works by gravity and is intended to prevent drafts from backflowing when the fan is off. Due to the high moisture content of the air passing through the fan/duct system the hinge part of those flappers stays wet and catches dust from the air, which forms mud and will eventually stick the door shut so even though your fan motor is running in cannot discharge air. At least once a year the homeowner should remove the cover over the fan unit and clean the dust and goop around that flapper to insure it moves freely. 3.Also check the discharge cover on the wall. Generally they are made the same way as a laundry dryer vent discharge and they also have a flapper inside that may be stuck, or you may find a birds nest or bee's nest under the cover which blocks the airflow. If the fan is sized correctly it should only need to run about 15min after the shower is finished. The solution is to install a 15min delay on break switch so when the fan switch is turned off, the fan will continue another 15min. I prefer to use a combination fan/light switch so the fan comes on any time someone turns the lights on in the bathroom. Remember the fan not only discharges moisture from the shower, it also discharges odors from body functions or hairspray and cosmetics so the fan should run every time your in the bathroom whether you shower or not. Mathematically the correct size fan for your bathroom is about 22cfm, but due to the length of your duct I would increase that to 30cfm. As Mongoct stated above, it is best to not use flex duct, however, I am not a proponent of metal duct either. Snap lock Galvanized metal and aluminum duct have a seam running the full length of each section. Condensate moisture will collect in that seam and collect dirt & debris. In addition, the galvanized metal duct is thin gage steel with a galvanized coating and it will rust and eventually cause it to leak. I prefer to use SDR-20 PVC pipe. This pipe has a thin wall and is only about 1/2 as heavy as the sched 40 PVC used for your drain, waste & vent systems and it is generally much cheaper than sched 40. You can usually find it in the plumbing supply at your local hardware or home supply. Look for 4" or 6" PVC pipe that has a light blue or light green color. When you install the pipe start at the discharge grille where it goes through the exterior wall and hang the pipe so it has a 1/4" per ft pitch towards the discharge end, that way any condensate that forms in the pipe can run to the discharge and go outside. The SDR-20 pipe has and end bell on one end of the pipe sections so you just slide one pipe into the next, It does not require glueing.

flseadog, I can relate to your situation because I, too, am considering the Panasonic because of its reported quiet operation. I had written out a lenghty post to you with my opinions, clicked the wrong button and lost it. ...AARGH! Returning to the Forum to rewrite, I noticed that jkom51 had posted the note above which makes a good point about the efficiency of the WhisperWarm related to the size of a room. I would have told you that I think the WhisperWarm would serve well in all 3 baths, based on my experience with another product. We used the Nutone heat/vent/light product for 25 years in my former Master Bath toilet/tub room. We hardly had to run heat for longer than 5 minutes (not 25) before the area (a mere 5' x 8') was toasty warm. I realize that this is a much smaller space, but the heat would always quickly spill out into the adjoining vanity/dressing area, leading me to believe that it would have warmed a much larger area. Since everyone raves over the WW, I just assumed that surely it must be better, or just as good. Perhaps the "heating for the volume of the room" as jkom51 mentioned, is an issue and you may need to consult an expert salesman. What we found was important was "heating a Hiney" once you stepped out of the shower, because everyone feels good with a warm Hiney. :) Therefore, my 2 cents: Bath 1: In this toilet-shower-soaking tub along one wall configuration, I agree that placing the WW in front of the shower would allow for direct heat when stepping out, as well as this central position would warm the room generally when you needed to take the chill out of the air. Bath 2: In an 11' x 6' vanity-toilet-shower along one wall format, I would position the WW between the shower and toilet, allowing for both bathing warmth and vent usage. Bath 3: Personally, I feel to use a WW in a 6' x 9' tub/toilet room is not overkill. You are looking for the CONVENIENCE of a heat/vent/light type product. We had the Nutone in a 5' x 8' tub/toilet room, and it worked just fine. Size appearance is another issue. Someone mentioned that the WW's grill is 18" x 16". The Nutone grill was 16" round, and it was attractive. I would suggest going to a dealer and actually seeing it firsthand, however. How much does the WW cost, anyway? Can anyone recommend an online source? Good luck with everything. My vote is on the WhisperWarm if 3 of them is in your budget.

Hi all--We had gotten sidetracked with other house projects and I'm just now returning to this one--delighted to see all the comments here since it's been a while since I checked! Update: We did finally take a much closer look at the fan a couple weekends back, and confirmed that it is an 80CFM WhisperFit-Lite model (alleviating my biggest concern--that our electrician had installed the wrong size!) Our next step is to try testing with/without duct attached, which we haven't done yet (requires getting up into our attic, which is an afternoon's adventure). We did the venting ourselves, but did use rigid metal ducting with insulation and a 4" opening, and it's a very short stretch directly out the roof, so I feel confident (after all the research we did on it!) that we tackled that job properly. My partner did spend a while up on a ladder with the fan running and reported that he couldn't feel or see too much air flow through it--I figure with a room that small, he ought to be feeling *something*, right? I'm very interested to hear about the backdraft tape issue, though--hoping maybe something as simple as that could be our issue?? Here's another question: we purchased our fan directly from our electrician as part of a bigger job, which I think isn't uncommon (at least around here). If we do have a bad fan, what ramifications, if any, does that have for the warranty? Do we have to get the original purchase documentation from him, or will Panasonic just take the serial number? And in situations like that, does the electrician come out and remove/reinstall and get paid as a new job, or should we expect him to do that gratis? (As you can tell, we're new to the world of contracting and home repair--wasn't sure what the norm was for something like this, if it does turn out that the installation was fine but the fan was bad.) Thanks! Diana

I have 2 Panasonic fans. The secret to any fan noise is proper duct work. This means as long a run as possible directly off the fan without changing direction or reducing size. Avoiding 90 degree bends - multiple 45's are better. Avoid flexible duct work like the plague. It's horrible stuff. Not only will it collect dust and moisture, the turbulence of the air caused by all those ridges contributes a lot to the noise level. Both my fans are exhausted to the outside with rigid duct work properly installed, taped (not duct tape - silver foil tape) and of course screwed together. They're very very quiet. Any fan is going to be much quieter with no ductwork attached, which is how they're demonstrated in big box stores which also are massive, tons of ambient noise etc. all making the fans seem quieter. Also don't oversize the fan for the cubic feet of the room. Very important, as is ensuring there is enough supply coming in under the closed door etc. to feed the fan. As much air as it pushes out of the room has to be replaced with new air coming in under that small crack under the door. If it's not getting enough replacement air, it will be noisier.