Retro fitting webasto heater

[PaulGH]

I’ve had my boat from new, built by stoke on Trent boatbuilders in 1998 and fitted with eberspacher which ran well but finally failed. Decided to replace it with Webasto as it is more modern with good reputation.   New heater installed by Stokeboats and connected to existing plumbing system . ( pipe work, radiators,  calorifier etc.)  heater starts and puts some heat into system but then shuts down.  Diesel feed has been bled as well as water system.  System incorporates header tank and is identical to system when Eberspacher was fitted, in fact only the final connections from pipewok to heater was changed. 

Any ideas please ????

PaulGH

[Boredrider]

Airlock?

 

Suggest you go on Ebay and get the diagnostic lead/software so you can see what the heater is actually doing when it shuts down. This will also enable you to run the pump on its own and get rid of any air.

 

You don't say what load you are putting on, i.e. are all the radiator valves open? Or are you just trying to heat the calorifier.

 

 

[PaulGH]

Hi, 

Thanks. I will get lead and software.

I've

Actually opened everything fully. 3 radiators with thermostatic valves, 1 fixed radiator open at all time and heater coil to calorifier.  

Help is appreciated.

PaulGH

 

 

[Boredrider]

Others on here will say that you shouldn't use thermostatic valves, although I do without any trouble.  You might also try opening the lock shield valves fully.  Are you getting any/much heat through to the rads before the Webasto shuts down?

[PaulGH]

Hi, 

Yes, the lockshields are all open.  Difficult to quantify actual temp but the first radiators get warm although the furthest radiator doesn't get as warm.  The heater stays on for about 10 minutes before cutting out.  I'm actually stuck in boatyard at moment and I think we are going to try and flush the system through on Monday and see if that makes any difference. Never been flushed in 20. The.small amount of water/glycol we lost when connecting up was reasonably clean but who knows what the rest of the system is like.  

Cheers

PaulGH

[Boredrider]

If you can point an IR thermometer at the return into the heater then that may tell you what is going on. Once the return gets up around 70C the heater will either cut out or drop to low output.  Flushing a 20 year old system must be a good idea!

[MtB]

This prompts a string of question in my mind, the first and most important is have you read the manual? They usually have a fault-finding section to guide you to a solution.

 

Assuming you have, and it doesn't, here are my questions:

 

1) You write as though you can repeat this 'cutting out'. What do you have you do to wake it up and make it run again, for it to cut out again? Pressing a button? Turning OFF then ON again? Waiting 30 minutes? Something else?

 

2) Are there any error codes showing on the display when it cuts out?

 

3) Is it the same heat output as the Eber you removed?

 

4) Is the pump built in or a separate component? (Did it get replaced?)

 

 

Edited August 4, 2018 by Mike the Boilerman

[Detling]

you may need to take the tops off the thermostatic valves in this weather to get them to open, I had to last week when repairing the Central heating at home even turned right up the thermostatic valves were still closed.

[PaulGH]

Thanks for that. I'll try that later on. I did wonder about the effects of the ambient temp. so I did first checks at 5ish when it was a bit cooler. Definitely worth a try though. Thanks for your suggestion.

Cheers

Paul.

[MtB]

1 hour ago, PaulGH said:

Thanks for that. I'll try that later on. I did wonder about the effects of the ambient temp. so I did first checks at 5ish when it was a bit cooler. Definitely worth a try though. Thanks for your suggestion.

Cheers

Paul.

 

 

So you're not planning on answering the questions I asked in post 7 then?? 

[PaulGH]

Just had to go out for a bit.

The Webasto manual does not have a fault finding section amazingly.  No error codes control shwitch/timer is very basic.

The fault is repeatable and to reset I take out the fuses, put them back and switch on.  The pump is built onto the unit and the whole unit is new. power is the same as Ebespacher. Initial start up yhe radiators get hot. At thjs stage I would expect the heater to idle or go into a low mode but instead it shuts down. This whole chcle takes about 8 to 10 minutes. What I've not mentioned is the boat is out of the water at the moment. Dont know if this will make any difference. 

Thanks

Paul

 

 

 

[MtB]

2 hours ago, PaulGH said:

Just had to go out for a bit.

The Webasto manual does not have a fault finding section amazingly.  No error codes control shwitch/timer is very basic.

The fault is repeatable and to reset I take out the fuses, put them back and switch on.  The pump is built onto the unit and the whole unit is new. power is the same as Ebespacher. Initial start up yhe radiators get hot. At thjs stage I would expect the heater to idle or go into a low mode but instead it shuts down. This whole chcle takes about 8 to 10 minutes. What I've not mentioned is the boat is out of the water at the moment. Dont know if this will make any difference. 

Thanks

Paul

 

 

 

 

Once it has shut down, how long have you been waiting before pulling the fuses to force a restart? It might just be up to temperature and shut down correctly. Leave it half an hour and see if it starts up again by itself.

 

Another possibility is you are pumping it through a calorifier perviously heated by the engine, which consequently heats it up hotter than the webby thermostat shut off temp. 

[Drayke]

Try going back to Stokeboats and ask them seeing as how they fitted it.

[MtB]

13 minutes ago, F DRAYKE said:

Try going back to Stokeboats and ask them seeing as how they fitted it.

 

A pound to a penny they'll have no idea why it does this. 

 

Fitting something doesn't mean the installer understands how it works, or has any sort of fault-tracing ability. 

 

My money is on them blaming the system it has been connected to.  

[PaulGH]

10 hours ago, Mike the Boilerman said:

 

Once it has shut down, how long have you been waiting before pulling the fuses to force a restart? It might just be up to temperature and shut down correctly. Leave it half an hour and see if it starts up again by itself.

 

Another possibility is you are pumping it through a calorifier perviously heated by the engine, which consequently heats it up hotter than the webby thermostat shut off temp. 

I'll try these ideas. Thanks.

[PaulGH]

Problem solved.  Amazingly it was a problem with the fuel supply.  

Thanks to everybody that helped. Much appreciated.

Paul