[wightsurf]

Has anyone fitted a DIY Diesel system in the Van ?
Been looking about and second hand water heaters seem cheap to buy.

[Spruce]

Has anyone fitted a DIY Diesel system in the Van ?
Been looking about and second hand water heaters seem cheap to buy.

Been messing on with something for a few years but nothing assembled yet. By the time I do it I will find the Thermo Top won't work anymore.

If you are looking at Webasto Thermo tops - be careful. The only ones we can used mustn't be vehicle specific. The ones that have come out of boats or universal are fine. However, the ones that a from boats would have been taken out because they would have been unreliable as they don't run on red diesel without coking up.

It could be that ones that come out of Rovers can also be used but are renowned for controller board failures. There is a guy on one of the Rover forums called French Mike who fixes them. He lives in France.

[wightsurf]

Just been reading about this topic on the other forum although a few months old.
Was it you that mentioned about heater size and that the larger unit is being used ?

[Small but perfectley formed]

why does red diesel effect them , its the exact same as the taxed diesel just dyed red.

[wightsurf]

To be honest I have not got a clue about these and always thought they cost thousands. But after spending a couple of google hrs this evening im beginning to think I can do this for under £400.00

Any good links for reading and advise on heaters to used would be good.
I have 2 gas L5 in good order that I have been using but would like to turn to Diesel.

[wightsurf]

This might be a stupid question but is there any reason I can not go and get one from the scrappy as there seems to be a lot of these webasto used in different types of car. My thinking is when it messes up just get another .

[Spruce]

Just been reading about this topic on the other forum although a few months old.
Was it you that mentioned about heater size and that the larger unit is being used ?

Probably. The 90 S is a more powerful heater but has a different burning configuration.

The Thermo Top is designed as an engine preheater. It runs on full burn until the coolant water temperature reaches 74 degrees C then reduces to half burn to 77 degrees C. If you draw heat off it down to 65 degrees is will then return to full burn. Once the temperature raises to 77 degrees c the heater turns off, job done. The problem with wfp is if we stop working the heater switches off, but has to restart when the heat is used. This takes battery power with each restart.

The 90 follows the same pattern (not sure when the full burn cut off point is) but goes onto reduced burn after that. The reduced burn is about a 1/3rd of full burn so produces less heat when compared to the Thermo Top. The Webasto 90S and ST are mainly designed as space heaters so will probably cope with wfp demands better.

I am planning to add a third water to water plate heat exchanger on my DIY system that will trigger a third pump at around 75 degrees c to keep the Thermo Top at 1/2 burn between 75 degrees and 65 degrees where full load operation kicks in again. The excess heat will be dumped into the water tank. That's the idea is to try to keep the heater running at 1/2 burn for extended periods of time well thats the plan anyway.

[Spruce]

why does red diesel effect them , its the exact same as the taxed diesel just dyed red.

Webasto have done extensive tests on red diesel and found that it is also a poor quality of diesel sold to the Marinas and causes excess coking up of the burner and heat exchanger. There is a report regarding this somewhere on the internet from them.

[KS Cleaning]

why does red diesel effect them , its the exact same as the taxed diesel just dyed red.

When you buy diesel from a forecourt you can be sure that the pumps and tanks are well maintained and free from any contamination, the same can't be said for red diesel.

[Spruce]

This might be a stupid question but is there any reason I can not go and get one from the scrappy as there seems to be a lot of these webasto used in different types of car. My thinking is when it messes up just get another .

They have different PC boards. A Thermo Top unit taken from a BMW only responds to the Canbus or Wbus (language) instructions that the BMW ecu talks to it in. A Webasto taken from a Citroen C5 or C8 isn't interchangeable as it speaks a different language to the BMW unit. Everything is the same except for the electronics.
 
Manufacurers also program different setting into the ecu to achieve different things. A few years ago Range Rovers had the Thermo Top working as a preheater and a supplementary heater for European spec vehicles. In the UK, the UK spec vehicle was programmed as a supplementary heater only. British owners were having their Range Rover serviced in France to stop the British dealers reprogrammimg their RRs to British spec everytime their vehicle went into the garage, even if it was just to have new brake pads fitted.  

There is a company in Germany (see German Ebay) that sells a Universal motherboard that would suit us for 130 Euros. You need to be able to use a soldering iron or have an electronics whizz do it for you. Once you have that pc board you can get any Webasto thermo top to work using it.

Another point to consider that you will usually have to buy a water pump, fuel pump, fuel piping, pipe stand, exhaust pipe and silencer, inlet pipe, wiring harness and electronic timer to get it to fire up. These items are expensive.

[wightsurf]

I have seen a second hand complete kit for sale at £350.00
But to be honest im not sure what all the parts are that im looking at.

How does this system work ? as its not circulating the water around a engine how does the burner drop down in temp?

As the water is heated up does it get dumped into a holding tank from which we then pump the water to our wfp ?

[Spruce]

why does red diesel effect them , its the exact same as the taxed diesel just dyed red.

When you buy diesel from a forecourt you can be sure that the pumps and tanks are well maintained and free from any contamination, the same can't be said for red diesel.

My brother in law bought an Alfa 157? diesel about 5 years ago. He loving put diesel additives into the tank every time he filled up. Every 6 months he had to remove the dpf filter and wash it out as the engine management kicked the engine into limp home mode. Eventually he listened and very reluctantly stopped putting additives into his diesel, and he then didn't need to clean the dpf filter out again in the next 2 years before he traded it in on a 4 x 4.

The diesel they sell on Marinas for long boats doesn't need to be quality stuff. Those diesel engines that chug along are the furthest from high tech you could ever get.

There is a local wfp business that has a hot box connected up to a separate tank filled with red diesel bought from a supplier that sells it to the fishing industry. The exhaust though his van roof is so sooty that his white van roof is black.

[Spruce]

I have seen a second hand complete kit for sale at £350.00
But to be honest im not sure what all the parts are that im looking at.

How does this system work ? as its not circulating the water around a engine how does the burner drop down in temp?

As the water is heated up does it get dumped into a holding tank from which we then pump the water to our wfp ?

It has its own heating circuit. The water is heated, goes through a heat exchanger into a header tank and back to the heater. In the circuit is a water to water plate heat exchanger which has 2 seperate water circuits in it. The one is the hot water being generated by the diesel boiler and the other is the cold water being pumped from your tank through the heat exchanger, to your hose reel and on up to the brush. This cold water zaps heat from the heat exchanger and leaves the exchanger hot.





The heat exchanger is above the heater and under the header tank. If you look carefully, the heat exchanger has 4 water pipes coupled to it. 2 are from the furnace and 2 are the circuit to the brush head.

[wightsurf]

ok, thanks I now understand that bit.

Now is there different size heat exchangers and is there a min spec I should look for ? And how  do you control the temp of water as you wfp pump is set at your own flow rate?

[KS Cleaning]

I have seen a second hand complete kit for sale at £350.00
But to be honest im not sure what all the parts are that im looking at.

How does this system work ? as its not circulating the water around a engine how does the burner drop down in temp?

As the water is heated up does it get dumped into a holding tank from which we then pump the water to our wfp ?

That is the way I use mine, I circulate the hot water into my 650 litre tank. You have to start off with a low flow rate as the ambient water temp in the tank is cold, as the water in the tank gradually heats up you start to increase the flow rate. This works best for me as I use backpacks.

[Spruce]

This is another view of a heat exchanger

[Spruce]

ok, thanks I now understand that bit.

Now is there different size heat exchangers and is there a min spec I should look for ? And how  do you control the temp of water as you wfp pump is set at your own flow rate?

Yes. This is what PureFreedom use.

http://www.ebay.co.uk/itm/WEBASTO-or-EBERSPACHER-Instant-Hot-Water-Heat-Exchanger-with-Mixer-Valve-/271200647299?pt=UK_CarsParts_Vehicles_CommercialVehicleParts_SM&hash=item3f24d17883#ht_1017wt_1141

I found a 20 plate heat exchanger 300mm long by 90mm wide for less than that off Ebay.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130977345127&ssPageName=ADME:L:OC:GB:3160#ht_198wt_1399

I plan to use something similar to this to keep the water temperature constant. The one I bought is adjustable.

http://www.ebay.co.uk/itm/BLENDING-VALVE-15mm-INTA-MIX-THERMOSTATIC-MIXER-CONTROL-FOR-TAPS-SHOWERS-/230867666362?pt=UK_DIY_Materials_Plumbing_MJ&hash=item35c0c905ba#ht_1095wt_1161

I also think a thermostatic shower mixer valve will also work well.

http://www.ebay.co.uk/itm/THERMOSTATIC-SHOWER-BAR-MIXER-VALVE-TAP-CHROME-/150842769850?pt=UK_Home_Garden_Bathroom_Shower_Units_PP&hash=item231eee01ba#ht_1824wt_1161

I started to make the first steel box to mount the exchangers in from angle iron - its still a long way from being finished.

[wightsurf]

Thank you, you have been very helpful.

Tried looking for that motherboard, but no joy. Will have another look tomorrow .

[Spruce]

Thank you, you have been very helpful.

Tried looking for that motherboard, but no joy. Will have another look tomorrow .

http://www.ebay.de/itm/Aftermarket-STEUERGERAT-fur-Webasto-Thermo-Top-Z-C-E-ECU-/161150986213?pt=DE_Autoteile&hash=item258558e7e5#ht_1283wt_1399

They have also reprogrammed this board with slightly different characteristics that would suit us better than the original Webasto unit does.

[Spruce]

You may find this interesting.

http://www.thefreeheater.co.uk/index.html

I'm not sure it would work for us, but there are a couple of 'interesting' application videos. they show a water to water plate heat exchanger working.