Heating question

[ttomas]

Hello folks,   I just finished tying in my heat system to the bus and I can not get any circulation.
    Facts:  mc9,6v92ta, 1983.  I removed the intire stock ac and heat. 
    I tied in the webasto system (minus the heating unit which I will add later)
    I removed the stock heater radiator and tied the new system of hoses into the existing lines on each side where it tied to the radiator.
    Is there a fault in tying it in here?  Thanks  tom

[Dallas]

Did you turn the valves on back by the engine and bleed the air out of the top of the engine?

IHTH

DF

[ttomas]

Dallas, that would be something I failed to do however I did double check and they are opened. Thanks, Tom

[Nick Badame Refrig/ACC]

Hi TT,

As Dallas says, Bleed all the air from the system, then do it again.... and again.....

Also, How much have you restricted from the lines from the 1 1/2" heat pipeing?

Let us know
Nick-

[DrivingMissLazy]

You will also have to bleed the air out at the heater/defroster.

Richard

[rcbishop]

Also, is your Webasto pump at the lowest point of the entire system?  Needs to be....and I found out the difficult way that it is a fine line.   Lowest point. Period.  Then bleed, bleed, bleed and probably do it again....as was stated above. Critical.
FWIW
RCB

[Tony LEE]

Remove the original water control valve as well?

[captain ron]

How do you go about bleeding air from your cooling system?

[DrivingMissLazy]

How do you go about bleeding air from your cooling system?

Cooling system or heating system?
Richard

[captain ron]

In his case I believe they are the same. In my case the engine cooling system and my heating system is or will be one and the same. But tell on both since they are evidently different methods.

[rcbishop]

In my case...I started with the Webasto pump (which happens to be a very large truck pump), the very lowest point in the system. Open the bleeder valve until a steady stream of coolant runs.  Then I started at the front of the coach, which is closest to the midships-engine configuration that I have.  The Cummins manual says to run the rpms to 1500 during the process; open the heat exchanger drain valves and repeat the process described at the pump.  Do the same for each heat exchanger in the coach until each, and every exchanger runs a stream of coolant.

Repeat, repeat repeat, till all signs of air i(bubbles in the stream) are gone.  I caught the collant in containers placed under each heat exchanger drain tube.  Little to no waste.  Be sure the radiator cap is off and the radiator is filled.during the entire process.  Time consuming, but well worth the effort.  You may need to do this more than once during the season depending on use of your coach and loss of coolant thru other circumstances.

FWIW 

RCB
'64 Crown Supercoach (HWC)

[bobofthenorth]

Bleeding tip - make sure you set the rads up so it is convenient to bleed them.  In my case that means a T fitting close to the rad with a 1/4 turn valve on one leg of the T & a short length of hose to direct the fluid to a container.  And you want the bleed point at high spots in the system so that the air will actually rise to the bleed point.  These rads are often in spots where they are "less than accessible" so take some time to set them up for future bleeding convenience.

My rads had built in bleed screws which apparently was all the previous owner ever used but they were a serious PITA not to mention messy so that was one of the things that got upgraded early on.

[ttomas]

Thanks to all for the advice. I ended up pumping water through the lines with a 12volt pump to get the air out of the system. Air was the problem.  Thanks again. tomas