All about heaters.

[Metalaroundstone]

Originally Posted by ncoonen

I have the deluxe heater box with factory air in my '65 C30. It has the under hood heater box on the right in the picture below. I am trying to R and R the heater core but I cannot remove the top from the heater box. I have removed all the sheet metal screws and the five bolts holding the warm air manifold to the firewall. Do I need to remove the whole assembly and split it open on the workbench? The under-dash situation inside the truck is more complex and cluttered because of the factory air so it would be nice not to have to disassemble all that to get to the mounting studs behind the blower motor.

Advice? Thanks!...ned.

I was in the same situation on a 66 factory AC truck. If I remember correctly, there are at least 2 sheet metal screws under the top vent that attach the diecast lid to the lower sheet metal tub. These screews are not accessible without taking out the entire heater unit. The good news is that if you don't reinstall the screws under the vent, you will be able to take out your heater core the next time without removing the entire heater.

[Oscar73]

I've been following this thread, and between the early and late heaters, Thrifty, Deluxe and whatever, I'm thoroughly confused.

Not one setup here matches what I have on my 66 C20. I HAD the left hand box here, in my truck, with a leaking heater core. Had spare heater box, like the right hand one with a decent core. Turns out to be about two inches shorter than he LH heater core. So, switched boxes. Everything went well, but I can't figure out where the heater cable connects to. There's absolutely no flaps, doors or valves in either of these heater boxes, and I haven't seen any in a single photo in this thread, other than the external lever on the side of the heater box which is connected to some mystery thing..

Am I crazy, or is something missing here? Thanks for any clarifications...

[/QUOTE]

PS - and how do you cut down a plastic blower fan? Seems like you'd just create some kind of bloomin' onion thing when the fan started spinning, since the blades would only be supported on one end...

[tc64]

went through the same confusing mystery,decided the only thing that mystery arm does is control the amount of water flowing through the core thereby adjusting the temp level of the air being blown in.Since i will probably run the heater on max when i do,I've decided to forget about that lever completely.

[Oscar73]

Originally Posted by tc64

went through the same confusing mystery,decided the only thing that mystery arm does is control the amount of water flowing through the core thereby adjusting the temp level of the air being blown in.Since i will probably run the heater on max when i do,I've decided to forget about that lever completely.

But I have no levers...just heater core. No flaps. Is there a mystery water valve that a PO took off? The original heater box does have a bolt welded in where a stud goes through the firewall... so somebody's been in there... Heater cable hooks up to a big nothing...

Pictures?

[Captainfab]

There is no ranco valve (water valve) on the '64-'66 heaters from the factory.

The Thriftair and Deluxe heaters will appear the same in the engine compartment. The Thriftair will have a smaller heater core than the Deluxe heater. The Thriftair heater has a single push/pull/turn knob inside the cab. The Deluxe heater will have 3 levers with knobs inside the cab. As for levers and flaps, the Deluxe heater will have a air flow flap inside the box in the engine compartment. It will be up close to the firewall with the lever arm on the right side towards the inner fender. This lever can be seen in the above pic at the top right. This is where the cable from the 'heat' control on the dash connects.

[Jferrante]

Originally Posted by Oscar73

PS - and how do you cut down a plastic blower fan? Seems like you'd just create some kind of bloomin' onion thing when the fan started spinning, since the blades would only be supported on one end...

Does anyone have an idea on this? I just bought the new plastic fan from LMC and it seems to be too big for the box...is shaving it down the answer?

[red450ih]

I recently purchased three new reproduction cables for my 1964 with Deluxe heater but the fit and quality is very bad.

Can anyone recommend a place to get high quality reproduction cables? I would also consider good working originals. A PM might be more appropriate.

Thanks!

[Jferrante]

Originally Posted by red450ih

I recently purchased three new reproduction cables for my 1964 with Deluxe heater but the fit and quality is very bad.

Can anyone recommend a place to get high quality reproduction cables? I would also consider good working originals. A PM might be more appropriate.

Thanks!

I am also interested in this - also is there a trick getting the cables off at the heater? Mine seems to not want to come off easily

[SBPage1]

Need some help. Took me awhile to find a thread that talked about heaters. Yes, these 60-66 heaters can be a challenge.

I have a 1961 C30 Apache Stakebed. I need to replace the Heater Blower Resistor. This truck has the recirculating heater. On this particular year, it appears that the resistor snaps into position on the backside of the heater box. Its difficult to get your hand behind the heater box to replace it.

Two questions:
1. Where can I get a resistor for this truck?
2. Any pictures for a breakdown on how to remove the heater box to replace?

I've attached a photo on how it looks. It was like this when I bought the truck. Only thing I can figure is someone took it out and couldn't get it back in.

[jonzcustomshop]

some good info in this thread:
http://67-72chevytrucks.com/vboard/s...d.php?t=690735

here is the main part:
OK I gave the local auto parts store another try. This time I decided to look under an alternate year. I noticed that there was a heater core for a "fresh air" heater and another option. "Re-circulation" or something like that. Under details of the heater core by Murray P#94691 the dimension of the core matched up and the picture looked the same. So I ordered that one. Well I got the core and installed it. It fit like a glove. no shimming, no bending or anything.

Lessons learned include:

always verify the guy behind the counter, unless you deal with vendors from this forum. They are pretty damn good at what they do.

ask for help and/or research this forum. There is lot of info on here.

Now we have two known part numbers for the suburban "fresh air" heater core

Murray Part # 94691 (O'reilys)
and
pro-source Part # 91691

[LostMy65]

What are some aftermarket options?

[LostMy65]

What makes the in cab (cheaper heater) less capable?

[jbgroby]

No defrost ductwork

[61K10]

I have the heater lostMY65 listed above. I modded a new fan and motor from a 96 air cond camaro. the thing will blow you out of the cab on hi lol.

[LostMy65]

Cool. I just picked one up in the forum's parts section. My other concern was how good does it work at defrosting? - beings it's recycling inside air.

[LostMy65]

I found a great reply by Mark about the Recirculating Heater:

Originally Posted by lakeroadster

Mark,

I would love to axe the under hood heater also. A couple questions for ya:
1.0 With the economy heater do you have problems with the windshield fogging over on rainy humid days?
2.0 Am I correct in assuming the economy heater doesn't provide any outside fresh air mixture into the heating mix?

Wonder why a guy couldn't cut into the cowl vent from inside the truck, thus pulling fresh air in without having the heater on the firewall?

You know me, always ready to cut something up!

.

Originally Posted by markeb01

Hi John, 1.0 - the recirculating heater isn't up to the standards of a modern fresh air heater, but it does heat the cab up well enough to be comfortable in sub freezing weather. Living in Idaho the lowest temp I experienced was about 17 below zero, but the coldest I generally drove in was closer zero - 10 degrees above. At those temperatures the heater needed to be on full defrost setting and high speed on the fan motor. 95% of the time it would keep the windshield completely clear, and when the center started to fog I just cracked the driver side vent window and that did the trick. Sounds unpleasant in those temps but wasn't bad with the cab warm (and wearing a watch cap). In temperatures closer to 30-40, medium fan and 50/50 blend between defrost/floor was enough.

In high humidity/heavy rain the heater has a harder time keeping the center completely clear, but again cracking the vent window and running the fan on high speed eliminates the fogging. Perhaps the 1960 fresh air heater I had never worked correctly, but it didn't provide any noticeable improvement in defrosting ability over the economy heater. My truck came stock with no heater, and a deluxe fresh air model was the first heater I installed. It chronically smelled like antifreeze in the cab, even though everything (core/seals/gaskets/hoses) in the system were new and there were no detectable leaks. The smell is why I got rid of the fresh air heater, and the econo heater has never had an odor problem - so lack of stink was more important to me than heater/defroster capacity, and I was driving 36 miles each way every day for 9 years.

2.0 - Correct there is no fresh air intake with the recirculating heater. If a person was creative enough with sheetmetal I suppose you could install a fresh air valve on the face of the firewall plenum inside the cab and route this into a recirculating heater with a little fab work. If it were on the bottom of the plenum it would probably leak water when raining. This could in turn connect to a completely different heater, although I'm not sure what would be suitable.

In my search for a heater that would actually function in a northwest winter, I tried:

1. Fresh air 1960 oem unit (smelled).
2. Old Air A/C-heater system (completely ineffective).
3. An electric van auxilliary heater (useless).
4. A Vintage Air street rod heater (inadequate heat and direction control).
5. A Flexalite Mojave heater (decent heat, no direction control).

Of the last 4, the only one that did any good at all was the Mojave heater mounted on the floor between the seats. It kept my feet warm and nothing else.

The econo heater doesn't provide performance of a modern heater/defroster, but it worked well enough to drive the truck everyday in the winter, and now that it's retired to hobby duty I'm glad to have it instead of the fresh air breadbox on the firewall. Good luck with whatever you decide to do.

.

Originally Posted by markeb01

Back when I commuted every day I'd always change my 160 degree summer thermostat to a 190 version for the winter months. Having 30 degree warmer coolant made a big difference. Didn't think to mention that.

[dieseldude4bt]

If you want fresh air with the econo heater crack the vent on the passenger side it pulls air from that direction.
I second that it is enough for winter driving as I live in Colorado and have been daily driving mine sense 1982.

[Palf70Step]

OK you heater experts, hopefully one of you can help my poor old brain out. I have 64 with deluxe heater. Finally getting things hooked up, but what I am wondering is what does each slider do.

Is up the neutral position?

I would assume that the heat one is temperature and the down position is a hotter heat, correct?

What does the center one do beside turn the fan on. There is a cable, but for the life of me can't figure what function it is doing?

The def slider, if that to change from defrost (down) to heat (up)?

Sorry if it sounds like stupid questions, but I haven't found any explanation anywhere and use to controls with different labeling.

Oh the only clear picture I had was one before I replaced all the arms.

Thanks all

[Vernski]

Palf70step all the way to the top on all three is the neutral or off position. Left side is defrost when it's all the way down it closes the baffle so all the air goes to the windshield to defrost, all the way up and the baffle lets all the air go to warm the feet. Right side adjusts the temp up and down the top is off, down is hot. The center control is the fan speed at top is off down a bit is low then medium then high all the way down. The workshop manual might have some info on the heaters I can't say for sure cause my knowledge comes from working on GM stuff for years it's been the same for a long time I believe. Hope that helps any....Vernski

[Pick121]

Originally Posted by Palf70Step

OK you heater experts, hopefully one of you can help my poor old brain out. I have 64 with deluxe heater. Finally getting things hooked up, but what I am wondering is what does each slider do.

Is up the neutral position?

I would assume that the heat one is temperature and the down position is a hotter heat, correct?

What does the center one do beside turn the fan on. There is a cable, but for the life of me can't figure what function it is doing?

The def slider, if that to change from defrost (down) to heat (up)?

Sorry if it sounds like stupid questions, but I haven't found any explanation anywhere and use to controls with different labeling.

Oh the only clear picture I had was one before I replaced all the arms.

Thanks all

I know this is an old post but, maybe others have the same questions. Here is what I found regarding the control knob settings for the 60-63 and also the 64-66. I have a 63 with 2 knobs and a 64 deluxe so, good to know both!

[Palf70Step]

I'll take experience over books most of the time. Thanks for the input Vernski. I just got the defroster tubes on imne hooked up right, so maybe I can tell the difference when I move the controls.

[akqj9]

I have a 64 C10 with the thrift heater (one knob). I'm trying to take the core out to check it and I undid 4 screws that hold it in place. Each time I hear something drop like a nut or clip to thread into. I can't get the top off since there seem to be 3 screws on the back side that I can't get to without taking the entire until out. Do I need to take the glove box out to get to the bolts that hold the unit in?

[Captainfab]

You will need to take the entire heater unit off of the firewall. There are 2 studs that have nuts on them on the inside of the firewall. Then once you have the heater unit removed, you can separate the top and bottom halves apart. Then you can access the heater core and the brackets that attach it to the top.

[akqj9]

Thanks. I hope the guy who designed that is rotting in hell. It should be designed so the core can be replaced without removing the entire unit.

[rvrfoot]

Thay are all a pain. I am doing a 1961 impala.