Battery charging and discharging issues

Can someone please advise me on some issues.
Firstly we are talking about a 10 year old vehicle battery in a vehicle that is normally on hook up and smart charger when at home, so I know that I am on borrowed time with the battery.

1. When on hook up without the smart charger, either at home or on a site, does the Sargent unit provide any charge to the vehicle battery or just the leisure battery?

2. Twice in the last six months I appear to have switched off the ignition and failed to turn off the dipped headlights  before doing so. On both occasions the van would not start, it just kept on clicking when the ignition key was turned. The last time was last week after possibly only 4 hours when parked up. Is it normal for this to happen after such a short time or is it just another sign of an old battery?

3. On both occasions I was 'lucky' to have someone close by with a set of jump leads. Having done this twice I then read that doing this can possibly damage electrics in the van. Is this true? If so why does Peugeot show how to use jump leads in their handbook?

4. On my previous van, a 2006 Peugeot based Compass I seem to remember replacing the battery by simply undoing it, installing the new battery and connecting it up. No problem. Now I read about people attaching an extra battery to avoid losing vehicle settings. 

We have only had the van for 10 years and we always seem to find something new. On our recent trip to the isle of Mull and Ardnamurchan I found out how to turn on the follow me home headlight function when I slipped and caught the headlight stalk. Life goes on it just seems to get more difficult.

1. The on board charger will charge which ever battery is selected on the control panel.

2. Head and sidelights will use approx 10amps, so for an old battery with reduced capacity, 4 hours to drain to no start is not unusual.

3.If you follow the Peugeot procedure, jump starting should not cause a problem.

4. Don't know if Boxer can sustain battery removal without loss of some functions, ie radio code. MB Sprinter it is no problem not using a back up battery.

Some of these questions can't be answered without knowing which Sargent unit you have. You don't say what year your van is, and it's not stated in your profile. If we assume that you bought it new, then it seems reasonable to assume that it's a 2011 Sussex Duo.

If that's correct then you probably have either an EC155 or an EC328? It's important to know this because later/higher spec models had "Smart charging" whereas the "lesser" models did not.

2. It depends whether this involved the dipped beams staying on for 4 hours. If they did then it would have taken 120 Watts from the vehicle battery for 4 hours, which would have severely depleted it. If, however, it only resulted in the sidelights being on, it should not have had too bad an effect (probably less than a quarter of the power consumption).

3. There is a small chance of damage to control modules during jump starting. Some vehicles are more susceptible than others - the VW T5 for example is a little more prone to failure of the ABS controller during a jump start. I don't know where the Boxer stands relative to other vehicles but I would guess that the chances of a failure are tiny (fractions of a percent, I would think). You can mitigate the risk by allowing several minutes of connection between the "donor" and "recipient" before trying to turn the engine over, so that the latter has a chance to raise its battery voltage. You can eliminate the risk by simply getting 240V power to the vehicle and putting the battery on a stand-alone charger instead.

[Edit: posted in parallel with Peter's post, but essentially we are saying much the same thing!].

if I switch off ignition without switching off lights, the lights go out anyway, same van same age.

Thanks for the responses. The van is indeed a 2011 model. 
The Sargent unit is an EC155. It is not something I have really looked at. Having now done so I see that here is a fuse allocated for the vehicle battery, so I presume that this does provide some charge to the vehicle battery, possibly only at a battery protection level.
I would have thought that by switching off the ignition the light switch would automatically be switched off. I habitually switch everything off, lights, radio, heater fan when stopping but last week when the van would not start I realised that I had left the light switch stalk in the dipped headlight position and therefore, very possibly incorrectly thought that this may have been the cause of the problem.
I am unsure how I can direct the charger to charge a particular battery. I understood that the selection button on the EC51 control panel allowed me to select which battery to power the leisure equipment in the conversion.

Whichever battery is selected on the control panel is the one that receives charge from the PSU charger (EHU connected only). The amount of charge is dependent on usuage of onboard 12v items.

Thanks for that.

pootler wrote:when the van would not start I realised that I had left the light switch stalk in the dipped headlight position and therefore, very possibly incorrectly thought that this may have been the cause of the problem.

This should not be a hard hypothesis to test. Simply go to the van, turn on the ignition, turn on dipped headlights, turn off ignition and go outside to check what lights remain on. On my van (VW T5) only the sidelights would stay on.

Therein lies my worry. If the light switch is left on and the ignition switched off no lights show. 
I was wondering whether any drain would be experienced with the ignition off but the light switch left in the on position.
However now trying to be logical I have switched everything off and disconnected the van from hook up. I shall leave it for possibly 4 hours and see what happens then. Following that I shall do the same withe light switch in the on position. 
I am not actually keen on trying to run the battery down but it does seem one way of trying out the possibilities.

The plot thickens. Methinks I need an electrician.
After five hours without anything switched on and no hook up, the van started well enough. At this point I tried the light switch and noticed that without the ignition switched on the green lights on the instrument console were on. I checked outside and the sidelights were on. I tried the dipped beam and these worked. I switched all lights off and tried to start the van. Not a chance, only the clicking noise that has been there on both previous occasions when it would not start. 
 I have put the van on charge and will give it an hour before trying again. 
The van is booked for a service in early July and I can bring it up then but do wonder if that is like giving Peugeot a chance to spend a lot of time, cost me more money than I care to think about and still get nowhere
Any electricians or otherwise out there with any ideas?