The Stovebolt Site Forums The Shop Area Interiors Ranco Heater Control Valves

I have three of them to go through. Does anyone have a procedure that works for rebuilding these valves? How do you test them? There is this copper donut in there that looks like it could be fragile. I will write a procedure for this but would appreciate any help getting started. From testing to rebuild info, I need whatever I can get. Thanks!

Talk to Alvin, I went through the unsoldering of the plug in the bottom even.
dg

Deve, when you click on this link you should be able to also see the next 4 or 5 pics. There are in my photobucket listed below and on page 10...or maybe it was 11.

http://i140.photobucket.com/albums/r19/LutherParris/52Panel/000_0188.jpg

Thanks. So the cap is soldered in place? What kind of solder do you use to solder it back? Like plumbers use for copper sweating? Also, did you install the kit they sell for this? What are the pitfalls I should be careful not to fall into? Where is a good place to get the kit? Any preferred vendor?

Also, this is a pretty rare item and I am wondering exactly what does this valve do and is there a modern replacement? There has to be more to it than just regulating the amount of water flow with the knob.

Deve, most of the time you don't have to take the soldered "cap" off. The stem just didn't feel right to me so I took it completely apart. Turns out one of the little "pointed guides" on the end of the stem was bent and it would not seat in the hole correctly. Look at one of the pics where you can see down inside the end off tube and you can see where the end of the stem seats.....you won't see that if you don't take the "cap" off the end.

There is only one part to the "kit". Its Balkamp #660-1000 at NAPA and a couple years ago cost $10. Its really just a "seal".

Advice?.... use a sharp thin blade to lift the tabs and I'd make sure they are "warn" as they may break off if its cold weather.
I used the regular soldering like I do for copper water pipes to put the 'cap" back on.
The is a long stem going to the valve that you turn which makes the valve restrict the flow thus reducing, or adding heat to the cab.....if I remembered this correctly. It was around 2011 when I rebuilt mine. I have also not used it as I decided to add the heat and A/C to my panel.

Hope this helps.

EDIT: Deve, just think of the valve as "temperature control" as that pretty much says it all. Its just and earlier version of what we have today!

Yep, big surprise when I bought the first one from NAPA. One
little seal about the size of a quarter.
http://www.pbase.com/dennygraham/image/113817419

Like Alvin posted, the biggest problems with rebuilding these
is the four tabs. As with any part that is not meant to be
disassembled, once the tabs are folded over you might get away
with unfolding them once, but not a second time.
Setting the tabs after you put the new seal in can be a
challenge. I made a special shaped driver and anvil to set
mine.
http://www.pbase.com/dennygraham/image/113817543

Before you put to much effort into one, make sure the tube
and diaphragm are still sealed and haven't developed a leak.
Freezer and boiling water test worked for me to verify that
it was still tight and working properly.

And to answer your question, about what it does....simply
controls the flow of water. Adjusting the knob simply moves a
cam putting more or less spring pressure on the diaphragm.
Not the most sophisticated thermostat in the world and
really doesn't regulate the heat level all that well.

DG

This is awesome. Thanks guys! It's important when writing about something that it makes perfect sense to me so let me see if I have this right...

The Ranco valve controls the flow of hot water to the heater. Turning the knob releases spring pressure and allows water to flow past the stem with the seal on the end of it. Also involved is a thermostatic valve that measures the temperature in the cab and regulates how much water flow is allowed to go to the heater assembly.

... would you say that any differently? What is the difference between this and a straight water valve with the rod and knob welded on the end of it? Not sure why we need a thermostat if we have to mechanically operate it anyway? I'm sure there is something I am not grasping. Thanks!

After a few hours of research on Heater Control Valves, I still dont understand why they use a refrigerant filled capillary instead of a screw. What am I missing? Does it have to do with finer tuning of the output? Isnt this the exact same thing as a standard through brass ballcock like we use on air compressors to regulate air or water flow? They went to alot of trouble to make these for all makes and models of vintage vehicles so there HAS to be a reason.

http://www.ebay.com/itm/Vintage-4way-Manual-Brass-Heater-Control-Valve-Everco-6746-/331553123734

The bellows/capillary is the automatic temperature control portion of the Ranco valve. The "Warmer" knob is for fine tuning the system to match the specific requirements of the vehicle.
Carl

How would a screw/ballcock continuously modify the flow of the fluid/coolant as the temperature in the cab changes?

The Ranco control valve is a feedback-control mechanism.

The sensor tube in the cab causes the valve to increase or decrease flow of coolant to produce the desired temperature in the cab.

Theory

The cab is nice and toasty

You open the doors when its 30 below zero.

The bellows notices the temp chance in the cab and changes position.

Once the cab warms back up the bellows reacts.

Probably never worked that way

Hehehe! Yep. It was a gallant effort though. I am skeptical because I am concerned about the longevity of 65 year old refrigerant inside of a copper capillary and bellows that is un-rechargeable. Doesn't it degrade over time?

I get what you guys are saying, but in reality, isn't turning the "Warmer" knob opening (or closing) the water flow to the heater core? You can do that with the one I posted above and have no refrigerant issues. Maybe that stuff lasts forever. From the way GM did everything else on these trucks, I do not think they were shooting for 100 years.

You open the cab and its 30 below zero outside, you get back in and turn the heater on HIGH, crank the warmer knob until you are happy again. Aren't you gonna be happy anyway?

The entire issue for me is a 65 year old bellows and capillary with unidentified, un-rechargeable refrigerant in it with no good alternatives. So the mindset here is, let's say the refrigerant lasts 65 years. What are our alternatives that allow us to keep things as stock as possible?

I got the last NAPA seal for this they have in their system.

No it is not. The warmer knob sets a max-temp point.

Theoretically, the ranco valve opens and closes a flow-valve to maintain the cab temperature at the warmer-knob set-point.

...and a lot of hot water circulating will keep things warmer than a little bit of hot water circulating.

Deve, the capillary tube can be refilled but if it is anything, cost wise, like the temperature tube, it may not be worth it.


(heck who needs a heater when we have global warming)
oops I shouldn't have said that.

I have never seen a service that does it. Have you? The web sites I have found so far can't even identify the type of refrigerant used.

I understand now what the thermostat part of this thing does, but so many of these things have bad capillary or bellows, the 65 year old gas in the thing seems like a questionable thing, and I am wondering what we could do to keep things as stock as possible with some improvement of some sort. I am not very knowledgeable on other makes, models, etc of newer vehicles to know if there is anything we can incorporate. I am thinking we should all ask Denny to set up a copper bellows and capillary manufacturing process!

Deve, its been a while but there was a thread going on here some time ago about the temperature tubing and I imagine it uses the same stuff...which I think was ether. And stuff about putting it in the freezer or something...I think Denny was a contributor to the discussion but my memory is fadddiiiinnggg.

EDIT: as I recall it was about 100 bucks to get a temperature gauge recharged. again, not sure about the heater control.

The temp gauges do use Diethyl ether. If you've ever broke
loose the temp bulb and noticed that sweet starter fluid smell
then you probably popped the seal. Ether's boiling point is
94.28°F and it doesn't need to boil to evaporate.
You can split the tube to the temp gauge, vacuum leak check
both ends and seal the leak. Then recharge the bulb, Keeping
it submerged in a bucket of ice will slow the evaporation
while you splice the tube. The question is, how much ether do
you charge it with to maintain the calibration?

The Ranco sensor is not filled with any liquid, it's simply a
sealed system made up of a diaphragm and tube. It's basically
just a simple type of barometer. It has to be vacuum tight
and the only way you could check it would be to split the
tube, vacuum or pressure test the two ends for leaks, patch
the leaks and then splice the tube. Having done High vacuum
leak testing on liquid nitrogen and liquid Helium systems
for many years I would guess that the weak spot would be
the diaphragm, which would be pretty tricky to patch.
Finding the right sized tube to use as a splice would be
another stumbling block and fabricating one from a rod would
probably be your best bet. And lastly, I'm not sure how you
would keep the air inside from collapsing the diaphragm as it
cooled after the splice was heated. I think during manufacture
the system was sealed at the very tip, very rapidly. putting
a heat sink near the end while you rapidly soldered it closed
might work.
If I didn't have a thousand things on the list that were more
important, I might try restoring either one of these. Maybe
if I live long enough I'll get down to the bottom of the list.

dg

Got the first one together, two more to go. Not sure why a special tool is needed to bend the tines. Is that special tool for the copper head with the two outlets, or the bellows? The copper tube was no problem just to do with a brass hammer and screwdriver wedged in to make sure it didn't bend outwards. The bellows is the hard one. For that I used 3 hemostats and a long needle nose. Once everything was pinched square, I put the needle nose almost across from the tine, then used a wedge on the top (to overcome a lip that wouldn't let the pliers fully crimp) and that worked pretty good.

In the end, I did something I learned years ago in the Air Force. I got a can of Freeze Spray and once it was all assembled, to test it, I shot it with the Freeze Spray to see if the plunger would move. It did quite nicely so it turns out at least on this particular Valve, the thermostat is working. Hot water out of the tap made for the Valve to move the other way. You can watch it working which instilled the confidence I needed to do the other two!

Thanks to all who posted. Your posts help a great deal in instilling confidence or at least poking me into doing a Hail Mary. I took a lot of pictures of each step and will be writing an article on this in the next few days. It is awesome to have you old timers (I'm getting there too) to step up to the plate when people have these questions. Hats off to you guys for sure!

One point of interest; this Valve came on all trucks of the time with the Harrison Deluxe Heater, and it did not come on the ones with the Fresh Air (round core) Heater right? If that is correct, what did the Fresh Air Heater folks do for thermostatic control?

Deve
The only options for controlling the output of the round cored, re-circulating heater/defroster is the fan speed or how much the manual valve on the engine next to the thermostat housing is opened up. heater/defroster shutoff control I think the proper name for the deluxe heater is the Fresh Air heater and the other is known as the Re-circulating heater.
Mike

Fresh Air and Air Flow were the names used for the heat-control-valve "deluxe" heaters between 47-55. From 53-55 these heaters were truly "Fresh Air" heaters, in that they had a control cable to let fresh outside air pass through the heater core (defrost was controlled by a lever similar to the lever on a Recirculating Heater). From 47-52, the control cable controlled defrost vs downward/floor heat.

As Mike posted, the 47-55 recirculating heaters did not have a heat control valve.

I can never remember the proper terminology for the heaters. I see what you mean Tim. I have a 53 heater here in the shop and it seems to be more functional than the ones before it even though the heater core is visibly smaller. If the core turns out good, I may put that one in my 50 Deluxe project. The bigger core (47-52) doesn't fit in the newer cases (without modification).

I had mentioned in a past Post that if you took the front cover and door portion of the 53-55 "Fresh Air" heater.
And put it on the front of the 47-52 Air Flow heater.

You would kinda have a hybrid heater with 2 control cables.
The 47-52 Air Flow heater control cable, directs ether defrost or floor air.
The 53-55 "Fresh Air" heater control cable, controls whether it recirculates Cab air or brings in fresh air.

I'm almost 100% positive the 2 front covers have the same footprint.
Put this front cover pic 1 & pic 2 on the body of this heater.

You would have to slightly modify the control cable attaching post to accommodate 2 cables.
Then find a spot to mount the 2nd cable knob, next to the original knob.

Hey, Deve nice mod on the Heater switch.
Resistors in the air flow.
http://devestechnet.com/Home/Native12VUpgrade#heatersystem
I had a hard time finding the link from your home page.

Thanks for that! There is a lot of stuff to do where Heaters are concerned. I have the 12 volt motor using the Stock switch figured out and have instruction there how to use a reducer, but there is more to do. I have a DC Motor controller on order that will be a solid state solution that we can use on not just the stock switch, but any of them. More bench tests to come...

Meanwhile.. I am not ready to debut that document in its entirety yet because it isn't finished, so that's why I use an HTML trick to get just the part I want people to see front and center. If you ever see a number sign in an HTML document, it's to send the user to the portion of the document they want you to see [<a id=heatersystem>]. The rest is all there if you scroll up, but it allows you to highlight portions of a bigger article.

Two more Ranco Valves to go!

It has been fun documenting all of this. Special thanks to Alvin and Denny for letting me use some of their pictures. Things work out so much nicer when everyone works together. As always, John and Peggy are told this every chance I get... What's mine is yours. You can put any of my articles here if you want.

Please proofread the document to make sure it makes sense to you. Often when it makes sense to me, there is something I could have said better. Don't hesitate to be critical. It's how we improve the document.

Entire Heater document is here:
http://devestechnet.com/Home/HeaterRestore

Ranco Information starts here:
http://devestechnet.com/Home/HeaterRestore#Ranco