webesto experts on here?

I was told we would have to pay £280 + VAT for the software for me to perform my own diagnostics on our Webasto Thermo 90 Pro hydronic heater (which currently ranks as No. 2 on the list of things that have caused hassle and expense since we bought the boat). At the moment we haven't even got a flash code output therefore I am trying to wire this in myself.

Sounds like a poor install by amateurs if that wasn't cabled in, it takes 5 minutes and is actually part of the standard switch loom, if so that could be more at the root of the issue than the heater itself. What controller do you have and what is the thermal load on the heater (calorifier aside)
 
You do know the Pro 90 cames with a three year on board warranty don't you?
Yes - but if we are in a location where there is nobody who deals with these heaters we may need to try and repair it ourselves if/when it goes wrong. We haven't gone far afield yet, still getting to grips with the boat, but this vessel is capable of crossing oceans and the time will probably come when we will be a long way from anywhere. I have a sneaky feeling that the heater will fail then, not when we are in the British isles.
Must be a hell of a size boat to warrant a Pro 90, unless the usual over specifying has been done
A quick glance at our video (link in signature bar below) will show you the boat. The furnace serves 4 matrixes (Saloon, Guest cabin, Owner's cabin and Pilot House) and a heated towel rail, and it seems about right. It certainly keeps the boat at an even temperature.
I can let you have a copy of the software if you wish, just drop me an email address. It is different to the old versions and gives a huge amount more info as the Pro series are a lot more complex tan the old 90 & 90ST, with internal exhaust temperature sensors etc which adjust the burn rate so servicing and adjusting is nothing like as simple as the earlier models. What you will need to buy is the interface hardware which I am sure nobody would expect for free. On the plus side you will be pleased to learn that Pro series parts are notably less expensive than earlier models.
PM sent, thanks
Sounds like a poor install by amateurs if that wasn't cabled in, it takes 5 minutes and is actually part of the standard switch loom, if so that could be more at the root of the issue than the heater itself. What controller do you have and what is the thermal load on the heater (calorifier aside)
The original was beautifully fitted - very professional, certainly not amateurish - the pipe runs and matrixes are installed very well indeed. The Thermo 90 Pro furnace is a replacement of the one which was on the boat when we bought it and which was checked by the installer as part of our survey. 6 months afterwards it blew up (actually it caused an explosion in a hot water pipe under the saloon settee) and after attempting to repair it we were told a new furnace was a better solution. What do we know? Nothing. Why would we? We are just ordinary boaters. I just wish we had a flash code display somewhere. I have been told that I can connect an LED to the white wire in this photo - or carry that wire to the control switch in the Pilot House - haven't had time to try that yet although I did go to Maplins and try to find an LED - not sure if what I have got is any good. Our controller is just a 2 position rotary switch marked "WEBASTO HEATER CONTROL". There is no timer control. I don't know what the thermal load is, unless my description of the system above is what you mean.
 
Yes - but if we are in a location where there is nobody who deals with these heaters we may need to try and repair it ourselves if/when it goes wrong. We haven't gone far afield yet, still getting to grips with the boat, but this vessel is capable of crossing oceans and the time will probably come when we will be a long way from anywhere. I have a sneaky feeling that the heater will fail then, not when we are in the British isles.

A quick glance at our video (link in signature bar below) will show you the boat. The furnace serves 4 matrixes (Saloon, Guest cabin, Owner's cabin and Pilot House) and a heated towel rail, and it seems about right. It certainly keeps the boat at an even temperature.

PM sent, thanks

The original was beautifully fitted - very professional, certainly not amateurish - the pipe runs and matrixes are installed very well indeed. The Thermo 90 Pro furnace is a replacement of the one which was on the boat when we bought it and which was checked by the installer as part of our survey. 6 months afterwards it blew up (actually it caused an explosion in a hot water pipe under the saloon settee) and after attempting to repair it we were told a new furnace was a better solution. What do we know? Nothing. Why would we? We are just ordinary boaters. I just wish we had a flash code display somewhere. I have been told that I can connect an LED to the white wire in this photo - or carry that wire to the control switch in the Pilot House - haven't had time to try that yet although I did go to Maplins and try to find an LED - not sure if what I have got is any good. Our controller is just a 2 position rotary switch marked "WEBASTO HEATER CONTROL". There is no timer control. I don't know what the thermal load is, unless my description of the system above is what you mean.

Frankly I can't see how the heater can be blamed for failed plumbing, possible boiling I guess, but I have never known that to happen as they have two overheat fail safes, even if one did boil, the plumbing (if professionally done) would have a PRV fitted just like a calorifier so probably as usual a heater being blamed when other factors are at least contributory if not the root cause. There is also the potential here if the original wiring was used during the replacement that the W bus diagnostic lead will not be there. If they used a new loom then all should be hunky dory.
 
Thank you all for the fantastic help given.

I have today started the project by getting my hands on a thermo top c complete with just no timer for a nice cheap price of £100.

As I've already got Eberspacher heating on board with a exhaust outlet could I be cheeky and t in to this and use the same outlet rather than a second hole in my hull, or will the back pressure of one running affect the other ?


regards

Ian
 
Thank you all for the fantastic help given.

I have today started the project by getting my hands on a thermo top c complete with just no timer for a nice cheap price of £100.

As I've already got Eberspacher heating on board with a exhaust outlet could I be cheeky and t in to this and use the same outlet rather than a second hole in my hull, or will the back pressure of one running affect the other ?


regards

Ian

Don't even think about it. Apart from anything the issue you mention you will get exhaust gas coming out of the combustion air intake of the other when run separately. Now starts the sourcing of all the parts you need, marine exhaust and silencer, skin fitting, loom, dosing pump, tank dip tube, copper or Tygon fuel lines and timer at a minimum.
 
Forgot to say, generally the white cable will go to the indicator lamp the bulb in which should be <2w the other terminal on the indicator lamp goes to the negative terminal. However I would always check on an install I had no previous history with that the cable goes to pin 4 on the main heater plug just in case.
 
Morning.

I did think that but i was hoping that i could be cheeky and get away without drilling my hull :-)

I have the fuel tank pick up in place and the dosing pump is with the heater along with part of a loom. The intake silencer is also attached with the heater and i have a spare Eberspacher D2 in the garage with all the exhaust bits in a bag.

So hopefully it looks like i now just need timer and loom and to extend the hoses on the hot water system and add a expansion tank.

As for the timer do i have to have one or can i just have a on off switch as discussed before so i can just turn it on with my other items when needed?


I think I'm pretty much nearly there i hope


thanks again


Ian

Don't even think about it. Apart from anything the issue you mention you will get exhaust gas coming out of the combustion air intake of the other when run separately. Now starts the sourcing of all the parts you need, marine exhaust and silencer, skin fitting, loom, dosing pump, tank dip tube, copper or Tygon fuel lines and timer at a minimum.
 
Morning.

I did think that but i was hoping that i could be cheeky and get away without drilling my hull :-)

I have the fuel tank pick up in place and the dosing pump is with the heater along with part of a loom. The intake silencer is also attached with the heater and i have a spare Eberspacher D2 in the garage with all the exhaust bits in a bag.

So hopefully it looks like i now just need timer and loom and to extend the hoses on the hot water system and add a expansion tank.

As for the timer do i have to have one or can i just have a on off switch as discussed before so i can just turn it on with my other items when needed?


I think I'm pretty much nearly there i hope


thanks again


Ian

When you say the air intake silencer is attached to the heater do you mean fixed where the circulation pump normally sits? if so you have an axilliary heater which has no trigger for coolant circulation. Picture of TTC with curculation pump attached. Also from memory the Eber exhaust is 24mm and the Themo Top is 22mm so not suitable, though I may be in error depending on the model.
thermo_top.png
 
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Are you connecting to the coolant side of your calorifer? If so, do you need an expansion tank as the engine has one?
 
TBH i was thinking of the lines of totally separating the system from the engine so the calorifer and heater was a dedicated system. But now you mention it Would it hurt putting the heater in line with my current set up but this would mean I'm heating my whole engine block up in the marina or at anchor just for a tank of hot water?

Ian
 
TBH i was thinking of the lines of totally separating the system from the engine so the calorifer and heater was a dedicated system. But now you mention it Would it hurt putting the heater in line with my current set up but this would mean I'm heating my whole engine block up in the marina or at anchor just for a tank of hot water?

Ian

True, but it also means you don't have to run the heater to have hot water if you have had the engine going. I guess it depends on your most likely use. Making it stand alone will heat the water quicker from a standing start I would have thought.....not as quick as a bloody great big engine at 4000 rpm though :D
 
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