TheSamba.com :: View topic - Connecting heat tubes - Samba bus -65

Sun Mar 17, 2013 6:06 am

Sorry if this question has been asked before, I couldn't find it.

Maybe someone more knowledgable than me can give information.

I'm connecting the engine heat to the front of the bus and have 3 tubes, connecting them the right way is puzzling me.

Tube nr 1 goes to the front and thats fine.
Tube nr 2 goes to the heat log under the rear seat. Thats also fine.
Where is tube nr 3 supposed to be connected?

Thanks a lot in advance for all useful tips.

Sun Mar 17, 2013 6:17 am

Tube 3 usually has a block off plug in it.
That opening is sometimes used to merge heat from a gas heater, or as some Canadians do, rig the drivers side heater box into it so all the heat goes up front- where we can better make use of it.

Sun Mar 17, 2013 11:20 am

Tube 3 is connected to the other heater box on single and double cabs. Generally plugged on others.

Sun Mar 17, 2013 12:19 pm

dmuis wrote: Tube 3 is connected to the other heater box on single and double cabs. Generally plugged on others.
#3 is only plugged on passenger buses which have the "heat log" on the floor under the backseat.
#3 is connected to the heater boxes on kombis and panels, too.

Sun Mar 17, 2013 2:00 pm

Thanks a lot, guys, for precise answers. Now it makes sense.

Two final questions:

1) What is the standard way to "block off" #3? Should it be welded?
2) What is normally used to lead the hot air into #1? flexi-tube? or just plain regular solid steel tube?

I am asking this since the existing connection looks kind of sloppy. After welding the double floor this parts become out of reach? (Wait a minute, maybe not, now that I look again at dmuis' pic...)

Flexi-tube:
http://www.biltema.se/sv/Bil---MC/Bilreservdelar/A...ror-79122/

Sun Mar 17, 2013 4:16 pm

There is a plug similar to a frost plug in Tube 3.
Generally a couple spot welds hold it in place.
The heater boxes are connected to tubes 1 and 2 through a flexible steel tube and then through a heater muffler. The muffler is necessary to reduce the engine noise transferred to the cabin.
If you do a search for heater muffler or something like that, you'll likely find pic's and descriptions.

Sun Mar 17, 2013 5:15 pm

Mon Mar 18, 2013 3:33 am

Thanks everybody for tips and pics, it's clear as a bell to me now.

A last question:

Is there a standard (most adequate) material to isolate the main heat tube under the cargo floor with or must it be a special order from VW dealers...?

(See left part of EverettB's pic)

Mon Mar 18, 2013 5:41 am

luftgekuhlt wrote: Thanks everybody for tips and pics, it's clear as a bell to me now.

A last question:

Is there a standard (most adequate) material to isolate the main heat tube under the cargo floor with or must it be a special order from VW dealers...?

(See left part of EverettB's pic)

http://www.thesamba.com/vw/forum/viewtopic.php?t=320691&highlight=heat+tube

This came up ^^^^^^^^^^^^ when I searched "heat tube", I'm sure their is more info here some where. I used a few sets of the OG grey wrap to do my Sc.

Mon Mar 18, 2013 6:04 am

luftgekuhlt wrote:
Is there a standard (most adequate) material to isolate the main heat tube under the cargo floor with or must it be a special order from VW dealers...?

From the classifieds:
http://www.thesamba.com/vw/classifieds/detail.php?id=1282828

Mon Mar 18, 2013 9:58 am

Ooooo I like that insulation kit!!

So here's a question. I tried to hook up my heater tubes last week only to have one of the springy steel tubes explode like a slinky as it was in pretty rough shape. I ordered some of the wolfsburg west replacement tubes which are a much different design. The replacements get rid of the muffler piece and instead have a spring loaded accordion-like design. Looking through the tube I can see that the insulation fibers inside is a bit ragged and steals about 30% of the diameter of the tube which Im guessing steals 30% of the airflow. Does anyone have an opinion on these? The heat just seems to warm the tube up front not really doing a whole lot.

http://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113255355M

Should I keep the WW part or find a replacement springy tube and go back to original?

Fri Mar 22, 2013 12:25 am

Has someone ordered from West Coast Metric Inc.?

https://shop.westcoastmetric.com/search.php?desc=211-725E

They carry insulation cover heater pipe, article # 211-725E but
are extremely laconic in their e-mail replies.

I'm trying to know more about their article, measure for instance
but all I get are onliners.

"They are sold in a 6ft lenght. So you need to figure out how many you might need."

I wrote again wondering about width, material. how cover is constructed, pics,

The answer until today is: SILENCE. No discernible signal.

Thu Jul 04, 2013 5:23 am

I am ready to insulate the center heater pipe of the bus. After researching different insulation options I have decided to use exhaust insulating wrap (aka exhaust heat wrap or exhaust wrapping). Yes I have seen the ad with pipe insulation special made for vintage VW buses for 180 USD + shipping.

I've done some research and given that:
1) The heater pipe is clean and free from rust, even surface rust.
2) It is painted with exhaust heat resistant paint
3) The exhaust wrap sits in water and citrus acid for a while and then is wrapped hard.

Then it would last for another 40 years. I have a double floor so it is a bit of a paradox. The double floor will protect the exhaust wrap from water and mud. But I will not be able to inspect it after the double floor is welded.

The exhaust wrap resists constant temperatures of 1100 °F and up to 2400 °F for short intervals.

Yes, I've thought of the humidity and rust problem. An advantage is having the pipe protected by the double floor. I would like to find something like the splits insulation of a grey plasticy layer. Whatever I use (and that goes for the exhaust wrap as well) I must be 110% sure that it resists the heat. Wouldn't like to cause a fire.

Specially knowing that exhaust wrap produces funky odors and sometimes even fumes.

What do the experts say?

Is my plan just neatly wrapped in appealing narrative, seeming perfectly reasonable as long as nobody examines it too closely?

What are the caveats? Appreciate your point of view.

Thu Jul 04, 2013 7:47 am

My take on this is that exhaust wrap is made for exhaust, not heater tubes.
It's main function is not to combust, it's insulating properties are inferior to other substances that do not need to resist high heat.
I have wrapped all my heater tubes in foil backed bubble wrap and have never had an issue with the heat being too high for the insulation.
The foil backed bubble wrap will offer substantially superior insulating qualities than a header wrap I think.

Thu Jul 04, 2013 9:55 am

Years ago I wrapped an exhaust with that stuff on my beetle. I lived in Florida where it rained pretty much every day... within a year my exhaust was completely rusted through. That stuff holds moisture...