better heater

[jwart]

just got back from 2week deer hunting trip. over 1000 miles in my 65 327/th400, with new heater motor & thermostat before i left. got most sheetmetal done on cab & blocked any drafts. also threw in temporary carpet as still in work mode on it.
But get down below freezing & it was cold. & trip home around zero for 6 hrs. & i'm looking for a better heating system. anyone grafted on a modern heater box/fan system into cab. looking for suggestions. looks like plenty of room & being able to better recirculate air in cab should help
at least i got venison for chile
thanks jw:


devil:where that heat when you need it!

[Captainfab]

Which heater do you currently Have? If you have the recirculating heater, that would explain a lot, those don't cut it in colder climates. A deluxe heater should be able to do a good job in a pickup cab. The only time a deluxe heater wasn't enough was one time in my Burb when it was a bit below zero.

[rickf]

Originally Posted by Captainfab

If you have the recirculating heater, that would explain a lot, those don't cut it in colder climates.

That sounds backwards to me. I am assuming the recirculating heater is recirculating the air.

I think the basic problem is that heaters like mine (believed to be Thrift Air, in 64 C10) is always heating outside air and blowing into the cab. So every bit of heated air is "from scratch". (The good side of this is that one is always getting some fresh air.)

A recirculating heater is going to heat the air, and then heat the same air some more, and then heat the same air some more... much more capable of getting the temperature up.

[Captainfab]

I guess I didn't word that correctly. The recirculating heater certainly sounds like it would provide more heat in the cab, but without outside air coming into the cab, the windows fog up and don't defrost worth a crap. Mind you this is in colder climates. It was always my understanding that the recirculating heaters were designed for areas that still required a little heat, but not where the temperature got say below freezing. Someone may prove me wrong on that......it's just what I was told long ago.

On the deluxe heater there is a flapper where the air comes into the heater box from the cowl that is controled by the 'HEAT' lever. As this flapper is closed the temperature of the air should rise since there isn't as much cold air entering the system.

[rickf]

Originally Posted by Captainfab

On the deluxe heater there is a flapper where the air comes into the heater box from the cowl that is controled by the 'HEAT' lever. As this flapper is closed the temperature of the air should rise since there isn't as much cold air entering the system.

I wonder if that really works. It sounds somewhat plausible, reduce the air flow so that the air that makes it through gets hotter. But how is that different from just setting the fan to a lower speed?

[jwart]

my heater appears to be heating outside air that is taken into heater box on outside of firewall where motor, heater core are located. i have the single pull knob-switch control type. i even tried to duct tape the intake area as much as i can reach. it did help some but not enough. is the deluxe heater box different arrangement of box, heater core & fan motor.

[Captainfab]

I haven't seen enough of the Thriftair heaters to know just what the differences are, I'm sure there are some. I'll bet LILRED66 (Tony) would know.
You say you put a new thermostat in, what temp did you use? Another thought is, some of the trucks had a control valve on the inlet to the heater core that after time can become partially clogged and therefore restrict coolant flow. Does yours have one?

[Oregoon]

Having a Burb and a perpetually cold wife, I've considered these options myself.

How about retro-fitting some seat heaters? Here's a kit for about $100. These are definitely on my to-do list.

You could hook 'em up with quick disconnects, and slip a seat cover over during winter months, then unplug and uncover for summer...

Wouldn't help much with defrosting, but it'd warm your hiney up nice and quick.

Being an avid coldwater surfer here in Oregon, I can't tell you how nice those things are after a few hours in the winter swells. My buddy's Nissan has them, and they're easily the best thing about the truck.

[rcrahn]

What is the condition of the heater core?
Old? New?
If it is old and plugged up you'll get little heat. Don't imagine a heater core for a 1965 Chevy will cost that much. Could be worth looking into.
Also, make sure you are running the correct thermostat.

[LILRED66]

Speaking from personal experience, I have had both Thrift-Air (2-speed) and Deluxe-Air (3-speed) heat/defrost systems, in numerous 4-5-6 Chevy trucks and most of the time, there is too much heat/cfm at full speed, regardless of the factory heater/defrost system I am running...please note this in assuming your fan motor, squirrel-cage fan, heater swithch/resistor, heater core, fan control switch, heater wiring harness, control levers, seals, defrost hoses and coolant flow are in order and working properly.

If the fan speed is inhibited, which is often the case, due to excessive corrosion inside the under-dash heater box, you will get decreased cfm airflow into the plenum box, thus reducing the distribution to the floor and the dash vents. Additionally, there is often blow-by, due to the plenum control flap not closing entirely, due to rotted seal or mis-adjusted control cables, that will also inhibit or allow air to flow when it is not called for or when you need it, depending on the resting position of the flap in the open or closed position.

In any case, I would check the performance and condition of all the components, prior to retrofitting another heating/defrosting systems, simply because the time, engineering, costs and head-scratching that will result in doing so, will far outweigh the time, effort and cost of tuning up your factory system. That being said, if you are still not satisfied with the heating capability of your factory system, I suggest installing sound mat and insulation in your truck, because it is amazing how much this helps, as well. With the relatively low cubic foot area of these cabs and the fact that they are like a tin can, with no factory insulation, to speak of, a 10-15 degree swing in temparature is a big deal when it is below freezing.

With regards to bringing "make-up" air into the cab or recirculating the air in the cab, you can do one or the other with the Deluxe-Air system. If you do not want to introduce heated air/make-up air, via the air circulated in/around the heater core in the heater box under the hood, simply adjust the center lever to the desired position...up for off...first detent for low...second detent for medium...bottom for high. This is due to the flapper in the heater box under the hood being closed, thus preventing heater air from entering through the firewall from the heater box/heater core...recirculating air in the cab with no turn-over or make-up air entering the cab. However, if you have an uninsulated cab, poorly performing heat/defrost system, not sealing up the openings in the cab, you will get a vast amount of unconditioned air into the cab from outside.

In the event you want heated air, you must set the postion of the defrost lever and heat lever, to the desired setting, to increase/decrease air flow through the respective diffusers to the floor or dash. All of this is based on a system that is properly operating and sealed. There is a seal at the firewall, as well as, a factory seam seal at the matting surfaces of all the parts, secured with the 1/4" screws, on the heater box under the hood, in addition to the contact surfaces of the blower motor to the heater box. Over time, these seals/seam sealer deterioates and allows moisture/outside air to infiltrate the system and cause damage and otherwise poor performance. A well tuned/maintained factory heat/defrost system is more than adequate to heat the interior of these trucks. I can't speak to the Panels/Suburbans, whereas I don't have any first-hand knowledge of them. I do know GM offered a factory/dealer option (R.P.O.-Regular Production Option/L.P.O.-Limited Production Option) rear heater for the Panels and Suburbans, so it is certainly plausible that the factory system did not provide enough heat/defrost, to adequately satisfy the owners originally.

PS-I replaced a fan motor on my '66 Chevy C10 with a new unit from O'Reilly (19.95 + tax, out the door), that had a factory Deluxe-Air system (three dash levers/3-speed fan switch) and the first time I turned it on high speed with the defrost lever/heater lever fully engaged, it blew a handfull of leaves and other goodies out of the plenum box under the dash and the dash defrost vents. I am telling you this, because it is amazing how much cfm is pushed through the system and how warm it gets when all things are operating properly. All of the parts listed above are available from your FLAPS (Favorite Local Auto Parts Store) in your area. I hope this information is helpful and let us know if you work out the gremlins and are able to keep your pigs toasty.

Happy Holidays!

[Captainfab]

Thanks for the detailed reply Tony

How does one determine if the resistor in the heating system is bad or not functioning correctly?

[jwart]

my resistor came out in peices when i cleaned out duct work. got new motor/Napa but had to wire it on high speed only for the trip. motors seemed & measured the same but cage had slop & slightly bent. someone had already done some epoxy to center hub but it was cracked out. i redid it & j-b welded so centered better on hub. but it kept interfering inside box so i had to space it down from box to keep it from hitting. i duct taped the gap between motor to box. i get heat but not alot of cfm. it defrosts windows ok but down around 10* it gets pretty cold. i still have to redo inside & out bottom of drivers door(already did passenger) but have closed up all drafts. trucks in progress but daily driver so trying to get by, not working & side work is dead also-$$$. did my 1st automatic,rebuild a junk turbo400 & got in truck the week before i left. 1000+ miles & only had to adjust modulator to get it working. going to try to get some deluxe heater parts from junker this weekend. temporarily going to throw carpet pad down for insulation everywhere. appreciate any help i can get.
thanks jw