Webasto Not Working? Troubleshooting Tips.

Hi, I've retrofitted a Thermo Top T (DW50) with a T70.
Actually, the thing was working quite well. Now, the system is exhibiting the following behavior:
When I turn it on with the remote control, the internal fan immediately starts, but the unit itself doesn't do anything. When the unit turns off after the set time or is manually turned off, the fan in the outdoor unit continues to run for about 1-2 minutes, accompanied by a clicking sound.
And then it's quiet again. Oh my god, why does this always happen in the winter?
Does anyone have a tip for me?
Thank you in advance!

When I turn it on with the remote control, the internal fan immediately starts, but nothing happens with the unit itself.
That sounds like the summer ventilation mode. This mode is designed for summer use. The heater won't turn on, but the interior fan will activate to blow cool outside air into the warm vehicle.
The summer setting is activated via an additional cable, which must be connected to ground. If this cable were to unintentionally short to ground for any reason, the result would be the same.

If the system shuts down after the specified time or is aborted, the fan in the STH starts running and a ticking sound occurs for about 1-2 minutes. Then it becomes quiet again. This doesn't sound like the summer mode operation...

I would suspect the diesel pump is the source of the ticking sound, and that pump only activates when the auxiliary heater is turned on and set to 'winter' mode.
It sounds like the auxiliary heater (when it's interrupted or after a set time) is briefly turning on to heat up and then turning off again.

Everything is very confusing to me. Although it's not really clear, I would check the cable for the summer mode function. (Possibly disconnect it directly at the auxiliary heater.)

Sorry, I don't have a better idea...

If you happen to have a diagnostic interface (e.g., for VAG-COM), you might be able to read the error memory of the auxiliary heater using a corresponding program. Do you have such an interface?

Regards,
Private.

Thank you for your reply!
I don't have a diagnostic tool yet, but that will be available soon. For now, I'm going to be able to go to a Bosch service center.
Do you think the electronics are messed up?

hi

"I also have a Thermotop installed. On the Thermotop T model, the fuel pump is connected to the combustion air blower, which is mechanically operated. The ticking sound starts as soon as the blower runs. However, the fuel is only pumped when the solenoid valve opens. Perhaps your flame sensor is defective. I could also send you the workshop manual."

Best regards,
Eric

I would also be interested in the workshop manual.

I've also had my fair share of problems with the Thermo Top T (diesel).

hi

Contact me.

[email protected]

Best regards,
Eric

I would also like the manual.
(I have a Tele Thermo Top T with a T70, which was only partially installed .)

With these symptoms, I would suspect a faulty temperature sensor.

Hello everyone, first of all, a huge thank you to Eric for the PDF!!!
It was the summer setting (which you have to figure out how to access on a T70 without instructions...) combined with air in the lines. I checked almost everything and reassembled the thing. First, I switched it to winter mode (without any comment...), and then I started the system while driving. That got it working again. Now it's nice and warm, and I don't have to scrape the ice anymore!!!!!!!
THANK YOU!!!

hi

You're welcome. I'm glad to hear that it helped you.

Best regards,
Eric

Hi everyone,

This post is quite old, but is it still possible for someone to email me the manual for the Thermo Top T?
That would be really great!

[email protected]


Thank you and best regards.
Wool.

Sure, here is the translation of the text from German to English:

'Please also send it to me again at [email protected].'