So to calculate your usage, 10 amps for 1/2 hour is 5 amp-hours (Ah). Then 1/2 amp for 24 hours is 12Ah. So you are using a maximum of 5 +12 = 17Ah per day. Your battery is probably about 100Ah,and you can use about 50% of that without causing problems, so that's 50Ah available. That should last you 3 full days. So yes, looks like the battery needs replacing.
www.alpha-batteries.co.uk
Same.
I don’t think so. The main draw on start up and shut down it’s the glow heater plug. By default settings, this plug is set at 90w plus the fan. The heater it’s a resistive load fed by DC, no pulsing, and you should not see a pulsing even with a oscilloscope. If you do, it’s a DC ripple due to high resistance for the draw: thin wires,weak battery etc. The pulsing will be in the 100hz region, with a peak of 0,3-0,8v. This difference in delta, can not account for the 10a difference you mention. I will be interested to know how you got the 20a. Maybe I’m missing something. The loom wire can be cut near the heater, and spiced with 6mm2 to mitigate the voltage drop, which I did.The heaters pull >20A on start up/shut down - not 10A. The 10A comes from the fact the power is pulsed so the meters only display an average of their delta, so show around 10A. The fact its 20A and the chinese heaters come with thin wires, mean many installs suffer from high voltage drop during this period and the heater drops out. Branded heaters also suffer but tend to be installed better. This is a large reason for startup issues.
In this case, once running (assuming its not on an on/off setting, rather than a run constant low) its likely to be either a duff battery or something else. The easiest way to check is turn it on in the morning with some lights on and see what happens. If it struggles to start and the lights dim/flicker - its almost certainly battery. If it starts, lights fine, and it (and other stuff) runs for an hour or two then look elsewhere,
I am aware of some branded heaters removed from commercial van have a 4hr (IIRC) timeout on them.
If it is your battery, find out make/model/size and get a comparable. Yes, some are better than others but thats a bigger debate
The 4 hours does seem a constant and a clue. I agree and this needs looking at first to be able to ignore it.
Those numbers sound about right to me.
I'd check with your scope
Not 100hz. The 10A ish is an average - and hence the higher current (pulsed) is more susceptible to voltage drop. (Had been discussed in depth on the heater forums). And yes, of course the power cables replaced with something of suitable spec. Only saw the flickering with one particular LED light range (which wasn't voltage sensitive). Anyway, our differing views aren't really linked to the OP apart from ensuring power cables are "severely over spec'd"
Thats quite different to ours, startup (from power on, to start cycle, to fan/pulse going to "normal" is closer to 5 mins, not timed it specifically, but certain its closer to 5 than 15 or even 10. Shutdown is about the same. Running power depends on fan speed and fuel pump pulse speed of course.Those numbers sound about right to me.
I did a power consumption check on the [chinese] diesel heater I fitted a few years ago in my last campervan. Logged from before start up to after shutdown.
The graph below shows the power consumption for initial firing, running and then shuting down. You can see the non-heater baseline from 14:15 onwards. Take that power off to see how much the heater itself uses ....
Heater Running - Power by David, on Flickr
If you prefer seeing it in Amps and effect on battery voltage ...
Heater Running - VoltAmp by David, on Flickr
Like Raul, I ran a thicker cable than supplied and cut off the great majority of the provided loom. I also, as a precuation to avoid having the heater not work due to inappropriate low voltage errors, fitted a 12V-13.8V voltage booster close to the heater and wired it via a 3-way switch so I could use with the normal battery supply or via the booster. (whilst fitted, I never actually needed to use it though. But for the cost of around £15, it was worth having ready)
I just noticed I also did a consumption test a bit later on (in October, so colder than above as it happens), seeing how much was taken out the battery over a longer period.
Diesel Power Test - Watts by David, on Flickr
Diesel Power Test by David, on Flickr
So 2.3 Ah to start+stop the heater and around 1.5Ah/Hr whilst it is running
About 5½ amps at full power a bit less than 1 amp at min fan speed with a CP Plus controller and 1¼ amps with a classic controller.
what diesel heater our autotherm lasts for hours with no problems, where is heater internal or underneath?, is your leisure battery under driver seat and getting hot maybe !!
I will check my own and see how it compares
I only have a choice of Eco or High.I will check my own and see how it compares
And using the set speed values rather than the auto-variable setting (you can select between the two).
Sounds quite inflexible?
That's not a Combi I thought all the Truma heaters in Motorhomes these days were Combi'sSounds quite inflexible?
This is what my fan controller looks like:
Middle is off
Switch on left, you set the fan speed between 1 and 5
Switch on right, you set the maximum fan speed between 1 and 5 and the actual speed will vary between off and the max speed set.
With this, you can use the fan to provide some airflow in the van with the heater off if you want. I would think with yours it would not be possible without having to put up with a very loud fan noise constantly?
5.5A at max seems remarkably high and inefficient. Just as I checked how the Diesel Heater used the battery, I did the same for the Maxxair Extreme Fan I fitted. These are very good and powerful (when you want them to be) fans - more so than the Truma fans I would say and don't use close to 5A at full power.
I'll be graphing the usage of the Truma Fan in the same way as I did the Maxxair (shown below). Information is Power
Maxxair Power Consumption by David, on Flickr
correct. It is not a combi
And I am pleased it is not.
Every van I've had has had a Combi I like them, nice to be able to set the timer and wake up in a warm van. Had caravans with the 3000 heaters.correct. It is not a combi
I have the Truma S3004 with Ultraheat 500/1000/2000 Element and a Truma Ultrastore with 850W Element.
www.fogstar.co.uk
I put a clamp monitor on my unit for 24hours. I found the initial start-up load was 15amp even with 6mm cables. What I did notice was that as the unit ramped down the current dropped off but when the thermostat called for heat the current again went up to 10-12 amps. I found that the glow plug was kicking in each time and thus hammering the batteries. I cannot say if this was just on my unit, but I have heard of many people waking up with flat batteries after using the heaters over night.
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