Not so much a question, well not at all a question!

Rumour

Rumour

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Electrical warning. I had been having trouble with the sporadic operation of my Eberspacher diesel heating system. At first we thought it was the batteries, but they are all good. Then someone told us that on some installations, the electrical wiring to the main heater unit may not be enough to power it up. So we decided that on our return from Blackpool, I would take a look.

We had just driven out of Blackpool when I noticed a high pitched noise. Had no idea where from but as I looked in the back through the mirror, I saw smoke! I pulled over and went back to investigate and found nothing obvious. But the smoke was getting worse and toxic! I lifted the seat cushions and opened the hatch into the side locker and there it was. Under a fitted rubber mat, was a tangle of wires. They had all seemed to have melted together. I disconnected the batteries and solar and the smoke subsided. (at this point, I was having a little difficulty breathing, so I got out of the van and took a rest.)

On looking at it, I saw that the had powered the heater from the inverter cables. They were much better able to handle to power loss over the 4 mtrs run. But they hadn't renewed the wire to the heater with a heavier gauge! Hence the heating of the mess under the seat! The thing is, the heater was not being used, so it was drawing no power. It happened during the day, so it made me think what if it has done that at night, while we were asleep. The smoke alarm didn't go off until I tested it and silenced it, then it went off! So it looks like I have to replace the whole thing at silly money.

BUT.. Although I am sure this is not really necessary, CHECK YOUR WIRING!

PXL_20231021_095501804.jpgPXL_20231021_155553473.MP.jpgPXL_20231021_155616720.MP.jpgPXL_20231021_155633972.jpg
 
Seems a bit weird to me :unsure:
The heater will be pulling around 10A Initially for about 10-15 minutes while it is warming the glow plug, and then go down to about 1A after that while running, so never at any time should a high current be being drawn.
The usual problem encountered with the wiring - and this is especially true of the Chinese Diesel heate copies - is the cable loom supplied is very long and the guage of cable used is too thin for that length. But ... It is too thin in terms of the voltage drop, and not in terms of its current carrying capacity.
Installers would/should either shorten the cable to the length needed and/or uprate the cable gauge to minimise the volt drop, otherwise what happens is not that the cable is overloaded, but the heater will just not start up due to insufficient voltage at the glow plug despite the battery being reasonably charged.

In the installation above, there would seem to be no effective fuse protection from energy source to heater (not fitted? way oversized?) to protect the cable in the event of a device failure or cable damage.
I don't know if the heater went bad in some way that created a short between the supply and the ground, or the supply cable was shorting on the chassis maybe (is it burnt all the way to the heater?), but either way, correct fuse protection would have stopped this happening.
 
Wow that must have been frightening , I had a problem with a new van the fuse holder burnt out but the fuse did not blow conclusion was very cheap fuse holder over heated fitted by manufacturer. Replaced fuse holder with high quality one never had any more problems
 
Last edited:
RAW said:
If someone fitted it then don't you have some recourse to go back to the fitter and ask for remedial work or compensation ?
Click to expand...
It was how it was when we collected the van nearly two years ago. The wiring was hidden under a rubber mat. I maybe should have checked it out.
 
wildebus said:
Seems a bit weird to me :unsure:
The heater will be pulling around 10A Initially for about 10-15 minutes while it is warming the glow plug, and then go down to about 1A after that while running, so never at any time should a high current be being drawn.
The usual problem encountered with the wiring - and this is especially true of the Chinese Diesel heate copies - is the cable loom supplied is very long and the guage of cable used is too thin for that length. But ... It is too thin in terms of the voltage drop, and not in terms of its current carrying capacity.
Installers would/should either shorten the cable to the length needed and/or uprate the cable gauge to minimise the volt drop, otherwise what happens is not that the cable is overloaded, but the heater will just not start up due to insufficient voltage at the glow plug despite the battery being reasonably charged.

In the installation above, there would seem to be no effective fuse protection from energy source to heater (not fitted? way oversized?) to protect the cable in the event of a device failure or cable damage.
I don't know if the heater went bad in some way that created a short between the supply and the ground, or the supply cable was shorting on the chassis maybe (is it burnt all the way to the heater?), but either way, correct fuse protection would have stopped this happening.
Click to expand...
The heater was working OK but sporadically. The feed from the battery had a blown 30 amp fuse in it, but that is not where the power came from to the heater. The person who fitted it knew about the wire being light, so he connected it to the inverter cables, with NO fuse at all! But didn't shorten the heater wires! Plus it was covered with a heavy rubber mat and was unseen by me.

What I can't understand is why it started to get hot while driving and the heater off. I guess it had chaffed over time and had finally worn through. I kept my small toolbox in that locker. We were lucky that it didn't go up at night. So now looking at getting a new heater, but I don't have the money for any state of the are Truma or similar. I discounted the cheap Chinese heaters after looking at the hundreds of Facebook pages to rectify problems. I'll have to just save my pennies and stop on sites with electric got the oil filled rad I have.
 
Molly 3 said:
Wow that must have been frightening , I had a problem with a new van the fuse holder burnt out but the fuse did not blow conclusion was very cheap fuse holder over heated fitted by manufacturer. Replaced fuse holder with high quality one never had any more problems
Click to expand...
We had similar, but on an old Talbot (I loved that van!) The fuses were under the drivers seat, I spelt some burning plastic and there between my legs was smoke! The holder had got hot and the fuses intact. Someone did say that it was cheap Chinese fuses, but they weren't. The auto electrical said it was a common problem on older vehicles, The fuses become loose as the holder gets older (that rhymes!) and causes heat. As you did, we had a good fuse holder fitted and it outlasted the van.
 
Guess there was enough heat to melt the plastic surround from the current pass through but not enough sustained peak current past the fuse tolerance ?
 
RAW said:
Guess there was enough heat to melt the plastic surround from the current pass through but not enough sustained peak current past the fuse tolerance ?
Click to expand...
thinking so. I am not sure what the circuit was for. I am not a big fan of using Spade Fuses on circuits where there is a sustained high current even if within the fuse capacity as they can get very hot due to either fuse or holder. This is one reason why rather than the Standard ATO Blade fuses in vehicles, you often see the Maxi Blade fuses even though the rating may be no greater than a standard. Much better contact area
Electrical_fuses%2C_plug-in_type%2C_different_sizes.jpeg


Personally, I like the Midi Fuses with the bolt-down contact area :)
 
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Rumour said:
Electrical warning. I had been having trouble with the sporadic operation of my Eberspacher diesel heating system. At first we thought it was the batteries, but they are all good. Then someone told us that on some installations, the electrical wiring to the main heater unit may not be enough to power it up. So we decided that on our return from Blackpool, I would take a look.

We had just driven out of Blackpool when I noticed a high pitched noise. Had no idea where from but as I looked in the back through the mirror, I saw smoke! I pulled over and went back to investigate and found nothing obvious. But the smoke was getting worse and toxic! I lifted the seat cushions and opened the hatch into the side locker and there it was. Under a fitted rubber mat, was a tangle of wires. They had all seemed to have melted together. I disconnected the batteries and solar and the smoke subsided. (at this point, I was having a little difficulty breathing, so I got out of the van and took a rest.)

On looking at it, I saw that the had powered the heater from the inverter cables. They were much better able to handle to power loss over the 4 mtrs run. But they hadn't renewed the wire to the heater with a heavier gauge! Hence the heating of the mess under the seat! The thing is, the heater was not being used, so it was drawing no power. It happened during the day, so it made me think what if it has done that at night, while we were asleep. The smoke alarm didn't go off until I tested it and silenced it, then it went off! So it looks like I have to replace the whole thing at silly money.

BUT.. Although I am sure this is not really necessary, CHECK YOUR WIRING!

View attachment 70131View attachment 70132View attachment 70133View attachment 70134
Click to expand...
There are a lot of those Chinese fuses around, most car shops and discount stores sell them, it should have blown, but normally they just melt everything around them.
 
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