Heater and Defroster

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tnswt12
Posts: 138
Joined: Sun Jan 07, 2018 11:31 am

Heater and Defroster

Post by tnswt12 »

If anyone has been searching for a schematic of the heater and defroster and specifically the orientation of the left and right flapper (located in the air vents) in regards to the cabling, and the control knob on the left, and the heater control at the dash, there is a beautiful explanation found in the 1957 Electrical Manual, page FS 970 and FS 971. I've looked everywhere for this and it was under my nose the entire time.

For those who have struggled with adjusting the cables that control the venting and the MagicAire system found in the small birds like I have, this is a monumental find, and I wanted to share it!
BuddyP
Posts: 36
Joined: Sat May 19, 2018 1:44 pm

Re: Heater and Defroster

Post by BuddyP »

Any chance you could scan those pages and post here? It would be appreciated.
ICON 1956
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Re: Heater and Defroster

Post by ICON 1956 »

I have always tried to help any member on this forum...But Big Brother sent me a notice of Copy Right infringement, on the manuals / pictures. So in the future if you don't have the materials you should buy the Books / Manuals. All I will do is mention page numbers. enough said.... :x
1956 Thunderbird Sage Green
1953 Ford Custom Liner Hot Rod With Flat 8 Motor with Henderson three 2 barrel Carbs
VTCI Member # 12309
fordrodsteven
Posts: 160
Joined: Mon Apr 24, 2017 7:46 pm

Re: Heater and Defroster

Post by fordrodsteven »

tnswt12 wrote: Sat Dec 01, 2018 1:01 pm If anyone has been searching for a schematic of the heater and defroster and specifically the orientation of the left and right flapper (located in the air vents) in regards to the cabling, and the control knob on the left, and the heater control at the dash, there is a beautiful explanation found in the 1957 Electrical Manual, page FS 970 and FS 971. I've looked everywhere for this and it was under my nose the entire time.

For those who have struggled with adjusting the cables that control the venting and the MagicAire system found in the small birds like I have, this is a monumental find, and I wanted to share it!
I found that when I put the flappers in they only seemed to fit one way. If I turned them around they didn't fit / seal properly. In my car they were sticking through the inner fender and the jog / step was facing upwards.
I have asked the moderator regarding some manuals / schematics and documents that I have due to ICON 1961's comment regarding copyright infringement. If I find the items I referenced are acceptable I will scan it in to show the diagram.
Steve - 1955 Thunderbird
tnswt12
Posts: 138
Joined: Sun Jan 07, 2018 11:31 am

Re: Heater and Defroster

Post by tnswt12 »

Regarding Fordrodsteven's comments about the flappers fitting only one way in the air duct, I didn't have that problem. It was necessary to replace the flapper located on the right side of my car because the membrane was brittle and did not afford a sufficient seal in both the heat position and the off position.

For those not aware, the left hand flapper is a 2-position flapper, off and fresh air; the right hand flapper functions as a 3-position flapper, off, fresh air and heat.

The flapper on the right side works harder than the flapper on the left because the right flapper membrane is required to seal the air duct when located in 2 positions, heat and off (for fresh air, the flapper remains center of the air duct). Since the membrane on the right flapper is required to flip from one side to the other for heat and off positions, this additional stress to the membrane causes it to wear quicker than the membrane located on the left flapper. Understand the left flapper membrane seals the air duct only in one position, off. The flapper remains center of the air duct for fresh air.

Anyway, the replacement flapper I used seemed to fit in either orientation i attempted to install it in. I tested the flapper both ways prior to installing the pin, but could not find any difference in the way in which it fit and sealed the opening. The flapper is flat, if it was convex or concave in nature it would mandate installation in a certain orientation.

I know there is the newer, fiberglass replacement air duct available from the part houses, but the flapper I installed was installed in the original, steel style air duct. That may be were the difference lies.
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