Gas heater debug

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ChickenPinz
United States of America
Posts: 113
Joined: Tue Feb 11, 2020 7:16 pm

Gas heater debug

Post by ChickenPinz » Tue Mar 17, 2020 8:19 pm

Looking for help debugging my behind-the-driver-set heater issues.

Pulling out the dash switch to the first detent, the fan starts running. That seems correct.
Pulling out the switch to the second detect, the fan stops slows to a stop and I hear 4-5 click/tick sounds from what seems like under the floor near the doghouse. The position of the control knob on the heater makes no difference. Test was run with the engine/ignition off.

Ideas of next steps in the debug process? Is there a good troubleshooting guide (AKA better than what's in the operator's manual)?
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Joeri
Belgium
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Re: Gas heater debug

Post by Joeri » Wed Mar 18, 2020 6:40 am


ChickenPinz
United States of America
Posts: 113
Joined: Tue Feb 11, 2020 7:16 pm

Re: Gas heater debug

Post by ChickenPinz » Thu Mar 19, 2020 2:05 pm

There is no apparent reset switch on this model that I can find.

When the switch is pulled out to the second position, all things slow to a halt (silence) and the dash light goes out.

Ideas?
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boeing7873
Argentina
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Location: Atlanta
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Re: Gas heater debug

Post by boeing7873 » Sun Mar 22, 2020 8:38 pm

I have posted somewhere around some diagrams, most likely for the old version, you have the new version, but still look around and you may find diagrams.
No experience with this model. You have two options, find those diagrams, then navigate through "the Samba" forums, and try to figure the problem out, or, contact Jason "notchboy" Weigel, to be found on thesamba.com forums, and ask for a quote to fix it if he is willing to do it. Maybe he can help over the phone...

The click tick click is probably your pulse fuel pump, that is what mine sounds like.

Jerome
Jerome
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boeing7873
Argentina
Posts: 179
Joined: Sun Dec 21, 2008 10:50 am
Location: Atlanta
Contact:

Re: Gas heater debug

Post by boeing7873 » Sun Mar 22, 2020 8:55 pm

I have posted somewhere around some diagrams, most likely for the old version, you have the new version, but still look around and you may find diagrams.
No experience with this model. You have two options, find those diagrams, then navigate through "the Samba" forums, and try to figure the problem out, or, contact Jason "notchboy" Weigel, to be found on thesamba.com forums, and ask for a quote to fix it if he is willing to do it. Maybe he can help over the phone...

Some links:
https://www.boote-forum.de/showthread.php?t=25797

https://www.youtube.com/user/notchboy1/videos

https://www.thesamba.com/vw/archives/ma ... ter_ac.php


The click tick click is probably your pulse fuel pump, that is what mine sounds like.

Jerome
Jerome
CRJ Driver

Derrickbwg
United States of America
Posts: 96
Joined: Sat Dec 16, 2017 8:09 pm
Location: TN

Re: Gas heater debug

Post by Derrickbwg » Sun Apr 26, 2020 9:34 am

mine works like this:

Pull switch to 1st position- light on dash comes on and fan runs.
Pull switch to 2nd position - light on dash goes OUT, fuel pump starts pumping to pressure level (the pulsating clicks you hear) and the igniter is powered.

When the heater fires up, the light on the dash turns BACK on ( mine takes about 10 seconds once pulled into 2nd position when its cold).

if at anytime after that you push the switch to close, the heater shuts off but the light on dash and the fan stay on until the unit cools off.

The light and fan will continue to run after the heater fires up and you close the switch to shut it off....even if you turn off the battery disconnect (it is wired that way to allow it to cool down regardless).

I had issues with mine firing up until I replaced the fuel pump and some of the lines. The old pump would sporadically click(pump) but the heater wouldn't start.
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djw
United States of America
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Location: Colleyville, TX

Re: Gas heater debug

Post by djw » Sun Apr 26, 2020 12:34 pm

I had problems until the gas line was replaced. You could hear the small pump tick away in the rf wheel well. Behind the shield in the wheel well the old line had become porous and allowed air in, making the suction pump suck air instead of fuel. Not porous enough to show any fuel leak. Most common problem with these heaters.

Once the line was replaced the heater works great. Apparently this is a common problem.
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ChickenPinz
United States of America
Posts: 113
Joined: Tue Feb 11, 2020 7:16 pm

Re: Gas heater debug

Post by ChickenPinz » Mon Apr 27, 2020 10:31 pm

Thanks, folks.

In my case, when I pull the dash control out to the second detect, the fans shut down and I just hear a few bits of ticking sound before silence, which I presume that is its fuel pump. Would I expect the heater's fans to shut down with a fuel pump and/or line issue?
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