Rear heated defroster H31 option question.

[b5blue]

I just bought a H31 option rear defroster to install in my 70 Charger. The ad said it has a 2 speed fan and electric heat coil built in, the whole thing mounts inside a rear speaker well. I'm just wondering if it is dealer add type option or factory order part? The correctness is not really critical to me as my car daily driver and no show car to say the least. Anyone have one they are using or know much about them? Seems like a neat package if it work out OK. I can post more details if anyone is interested.

[Dodge Don]

Quite a few 70 Chargers came with the H31 rear defroster option so it isn't rare. On cars without dual rear speaker option the defroster was mounted in the rear passenger side speaker hole. On cars equipped with the dual rear speaker option then the defroster was mounted to the cross supports and draws air from the cavity behind the rear seat.

[b5blue]

Thanks! So it is even "correct"! All I ever saw was the slotted kind on ebay for sale. Florida is so damp sometimes for days the back window is white.

[Nacho-RT74]

the heating element is certainly not true.

The blower housing carries a resistor coil to reduce the speed when setting low speed from dash switch. Is mounted on housing to keep cooler the resistor like the ones on front systems, mounted on fiberglass boxes

[maxwellwedge]

The 69's were single speed blower only....I don't have a 70 with that option but would think the motor would be similar to a 69.

[Dodge Don]

70 is dual speed.

[b5blue]

So the "Heating coil" is just the low speed resistster.  I just hope it works!

[Dodge Don]

So the "Heating coil" is just the low speed resistster.  I just hope it works!

Well I don't know jack about that however the dash switch lets you turn it on low or high fan.

[maxwellwedge]

70 is dual speed.

Cool - "Dint" know dat! 

[WINGMAN]

 My 69 C 500 has the rear defroster H 31 option, blower has two speeds and only clears the top part of the glass do to the position of the vent, it also has four 1/2 inch intake holes in a diamond pattern on the right side of the package tray. GG told me some years back that only three or four C500s had the H 31 option but who knows?    Jay.

[Nacho-RT74]

So the "Heating coil" is just the low speed resistster.  I just hope it works!

yeap!

[b5blue]

Well Thanks Again everyone! 

[maxwellwedge]

My 69 C 500 has the rear defroster H 31 option, blower has two speeds and only clears the top part of the glass do to the position of the vent, it also has four 1/2 inch intake holes in a diamond pattern on the right side of the package tray. GG told me some years back that only three or four C500s had the H 31 option but who knows?    Jay.

Hmmm - I have 2 '69's with it - I should check the speeds huh? I was assuming again...

[66FBCharger]

How rare of an option is it for a 69? Does anyone repro a kit to retro fit to a car that does not have one?

[b5blue]

The whole thing fits in a speaker well, intake on one side, exhaust on the other.

[b5blue]

Well it came in today and one look shows Nacho is correct! (Again!  ) The coil in the duct is the low speed resistor, the set is complete and in very nice condition, I will have to clean the connectors for the harness as it would not run with everything hooked up but the blower runs nice on both speeds when jumped. All in all for 50.77 shipped soon I can stop wondering whats going on behind me! Can anyone tell me the correct place the switch is mounted on a 70 Charger?     

[Dodge Don]

http://1970chargerregistry.com/Misc/owners_manual.html

http://1970chargerregistry.com/Misc/owners_manual/5.jpg