myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website
Welcome to myHanse.com the forum for Hanse Yachts owners throughout the world.
Forum Home Forum Home > Hints & Tips > 341 / 342
  New Posts New Posts RSS Feed - Webasto Thermo Top only starts with shore power
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Webasto Thermo Top only starts with shore power
 Post Reply Post Reply
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
OnkelHugo View Drop Down
Sub Lieutenant
Sub Lieutenant


Joined: 07 June 2025
Status: Offline
Points: 2 		Post Options Post Options   Thanks (0) Thanks(0)   Quote OnkelHugo Quote  Post ReplyReply Direct Link To This Post Topic: Webasto Thermo Top only starts with shore power
    Posted: 09 March 2026 at 08:46

The Webasto Thermo Top heater on my 341 only starts when the boat is connected to shore power. I suspect the issue is either a dirty glow plug or a problem with the wiring.
Can anyone tell me where the heater is actually connected?
Since the cables run inside the cable duct, I can’t trace them back.
Back to Top
Arcadia View Drop Down
Admiral
Admiral
Avatar

Joined: 27 November 2017
Location: Sag Harbor, USA
Status: Offline
Points: 1112 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Arcadia Quote  Post ReplyReply Direct Link To This Post Posted: 09 March 2026 at 09:17
Is it possible that Hanse did not want the heater draining the batteries. Also be aware there is a low voltage cut off designed into those units. 
Leon / ARCADIA
2018 Hanse 588
Sag Harbor, NY
Back to Top
Brufan View Drop Down
Rear Admiral
Rear Admiral
Avatar

Joined: 16 December 2010
Location: Belgium
Status: Offline
Points: 672 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Brufan Quote  Post ReplyReply Direct Link To This Post Posted: 09 March 2026 at 14:33
1st Consider rusty connections or cables.  Hanse cabling is always on the thinner side.  Just the minimum for the loads.  If any oxydation occurs cable cannot do its duty anymore.
2nd If ok, check battery state of health.  Maybe they are outdated/worn.
Then, 3rd check glowplug
Bruno

hanse 355 - 57

S/Y Spicy Ginger

White hull, 2 cabins, Volvo D1-30, Selden rig, removable mainsheet track system, Simrad (now B&G)-Jefa autopilot.
Back to Top
Martin&Rene View Drop Down
Vice Admiral
Vice Admiral
Avatar

Joined: 06 December 2009
Location: United Kingdom
Status: Offline
Points: 967 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Martin&Rene Quote  Post ReplyReply Direct Link To This Post Posted: 09 March 2026 at 16:25
Brufan is correct.  From memory, Webasto heaters need 10.5v at the heater.  So check  to see difference on battery and on shore power.  This problem told me I needed new batteries and prompted my installing a Sterling alternator to battery regulator

If heater fails to start, I think there are error codes given by flashing lights on the control panel. (look for manual online) which can identify problem.

My heater is in back locker, so not ideal, so definitely clean connections.  The other end of wiring will just be at your controller.

There is often a comment that it is not good practice to run them at a low setting for long periods as they can get a build up of muck, so give it a full power blast.

I am holiday now, back home next week when I can look at manuals and hopefully back on the yacht in the next 3 weeks to look at installation
Martin&Rene Hanse 341 Dipper Wheel steering, 3 cabin layout, normally based in Scotland
Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2023 Web Wiz Ltd.

This page was generated in 0.156 seconds.
Links : www.hanseyachts.co.uk www.hanseyachts.com www.fjordboats.co.uk www.dehler.co.uk www.varianta.co.uk