47-55.1 Deluxe heater

[Matt_50]

I want to use a fresh air deluxe heater. I really like the look of it hanging under the passenger side with the emblem showing.

My question is about the heater core and the pressure they are rated for. This link says not for modern applications without the 4# cap.


https://www.classicparts.com/mobile/...ctinfo/68-221/

I've done a v8 swap. Lines are currently capped. What pressure runs through it now and can it be reduced?

What have some you guys done when swapping engines and keeping factory heater?


Matt

[Divine 59]

Someone correct me if I am wrong. But doesn't your radiator cap spring control the pressure of the cooling system. The spring give and releases pressure allowing the coolant to route to the overflow line that goes on the ground or to an overflow tank. ???? At least that is my understanding...

[Matt_50]

I think so. Wants it reaches a certain pressure thevrest is spilled out. The truck my engine came out of had a 16# cap and the radiator itnis with now has a 19# cap.

Higher the #s the higher the boiling point and that's good right? So how do you guys retain factory heater? Is there a way to reduce pressure towards heater core?

[Divine 59]

Sorry Matt_50 I am running my truck mostly stock. So I can't help too much with suggestions to reduce the pressure at the heater core.

[mr48chev]

I had to hunt a bit but they say this unit handles the higher pressure. https://www.classicindustries.com/pr...ts/cx1994.html

You would need a 12 V fan motor too.

[Matt_50]

Thanks! I'm so used to searching the same vendors, I was flipping through all my catalogs.

Motor wasn't a big problem to find since a 12 v conversion is common. Options are 12v motors or a reducer.

[Matt_50]

I found some old postsvwhere ppl tried searching for modern replacements that could be tweaked to fit. I guess the above one has come out since then.

[47 Fasttoys]

FWIW, I have been running my factory Deluxe heater with original heater core for over 160K miles with zero issues. I also run an LS engine with a 16PSI cap.

[mr48chev]

I'd think that someone may have changed that core to an aftermarket one that was actually but possibly unintentionally made to handle the higher pressure. Or it had been re-cored at a radiator shop at one time.

The cost for one that will handle the pressure is the same as the cost for one that handles a 4 lb cap now.

I've got a few of those heaters around but don't know if any of them can be made show worthy presentable.

[Matt_50]

I have found a few repop original style types and I'm up to two that can handle higher pressure.

One you found and one from bowtiebits. About same prices and the 12v conversion is popular enough that there are plenty of listed motors that'll work.

Trying to get all my ducks in a row lol. I wanna drive it, but I don't wanna freeze!

[mr48chev]

No more 35 dollar heater cores from the parts houses on these trucks. I'm going Vintage air heat and air on mine. We have some seriously long road trips planned and comfort is a must as we have earned our no AC creds years ago.

[_Ogre]

the higher pressure cap you run the higher the boiling point of your coolant
water boils at 212F at zero pressure
with a 15 lb cap the water boils at 248F, i believe coolant is 265F
it can make a difference of driving or not
i run a 16lb cap on truk

fwiw... water at 700F and 3000psi won't boil

[vintovka]

After freezing my (now sizeable) keister off for 50 years, I decided against replacing my wonderful, original "fresh air" Chevy badged heater with a with a big one from Jegs instead. (The funds from selling the old one paid most of the new.) The new 3 vent job gets warm within minutes and defrosts the windsheild like a flame thrower. Its so efficient it still gets very warm even if the heater shutoff is on. I run it for about 3 minutes and then shut the fan off and its keeps the tiny AD cab warm for a long time. I do like the looks of the Vintage aire one but not sure you really need the temperature control at all.

[vintovka]

The upside down bandit strikes again!!!

[mr48chev]

Fixed it, I was getting dizzy trying stand on my head to look at.
That might not be pretty but having froze my butt off for more winters than I want to remember it sure looks interesting.

[vintovka]

Thanks for the fix. I have no idea what makes em upside down like that. Heres the finished product. Used first duct with abs drain ells to route up to defroster. Not pretty but fits with the military/utilitarian theme of the truck. Other two have aftermarket adjustable vents which are closed in pic. This thing is the most powerful heater/blower i have ever seen and think its for heating open fishing boats. Defrosts easily with all vents wide open.