Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Discussions => Topic started by: Numbers on May 26, 2017, 09:50:50 am

Title: Dash A/C booster fans
Post by: Numbers on May 26, 2017, 09:50:50 am
I have appreciated the discussion in the thread "Dash A/C Question".  Some the recent replies got me thinking about ways to increase air flow in the ducts.  It seemed good to start a new thread.

It seems one of the big problems with the dash A/C in the late 1990 model U series coach is low volume of airflow out of the vents on the passenger side.

I was wondering if installing muffin fans as booster fans inline on the ducts would help.  Some home HVAC systems have booster fans to help move the air.

I was wondering if it would be possible to use a 12 volt computer muffin fan sandwiched between something like  a properly sized Valterra sewer flange (the part the goes on the back side of a Bladex gate valve) to create a booster fan that is installed inline on the dash ducting.

Our coach is in for service right now so I can't check the size of the duct.

Wondering if anybody has any thoughts about increasing airflow with this method.

Thanks,
Chris
Title: Re: Dash A/C booster fans
Post by: Caflashbob on May 26, 2017, 09:56:56 am
I'm all eyes on any way to help the dash air. Please
Title: Re: Dash A/C booster fans
Post by: Racedad on May 26, 2017, 10:04:37 am
Bilge blowers move about 170cfm and are 3"/12v.
Title: Re: Dash A/C booster fans
Post by: Numbers on May 26, 2017, 10:09:01 am
Bilge blowers move about 170cfm and are 3"/12v.

I had not seen these before!  They are very affordable.

If the dash duct hose is also 3" then this is the type of setup I was thinking about.

Chris
Title: Re: Dash A/C booster fans
Post by: krush on May 26, 2017, 10:39:02 am
Bilge blowers move about 170cfm and are 3"/12v.

and most are VERY loud.
Title: Re: Dash A/C booster fans
Post by: Dick S on May 26, 2017, 10:58:08 am
I'm with Bob. Air flow especially for defrost is poor. Have been thinking of replacing some of the ducts due to kinking a bends. Just don't know what to use.
All eyes here too.
Dick
Title: Re: Dash A/C booster fans
Post by: craneman on May 26, 2017, 10:59:59 am
I'm with Bob. Air flow especially for defrost is poor. Have been thinking of replacing some of the ducts due to kinking a bends. Just don't know what to use.
All eyes here too.
Dick
The AH works for an excellent defroster.
Title: Re: Dash A/C booster fans
Post by: John Duld on May 26, 2017, 11:34:46 am
When I replaced the dash air/heater blower motor ( a lot of work ) I cleaned the veins on the squirrel cage blower wheels. They were incrusted with hard dirt that had reduced the shape of the veins by quite a bit. The new motor and cleaned up blower wheels made a nothicable increase in airflow.
My blower chattered on start up and for the first few minutes of use so I had to change it. On my coach I was able to get the blower assembly out without breaking the freon lines. Foretravel quoted ten hours to change mine and that probably did not include cleaning the blower wheels.
Title: Re: Dash A/C booster fans
Post by: Caflashbob on May 26, 2017, 11:47:40 am
I thought about the dirt buidup on the wheels.  Hmmm 10 hours.....