The continuing saga of the motorhome discharging batteries

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 The sagas of discharging batteries

When you are a newbie to anything, there is a very important phrase to remember

”You don’t know what you don’t know”.

And this is the case with our motorhome batteries. This is the first motorhome we have owned and this is our first winter with Bryony in storage. A previous post about our battery woes can be found here at: https://wherenexthun.blogspot.com/2020/12/managing-batteries-in-autosleeper.html

Bryony at Dawlish just after lock down was lifted before Christmas 

Our winter ‘battery management’ plans to take Bryony out once a fortnight over winter to charge batteries during day and overnight visits throughout Devon and Cornwall have been curtailed by lock down. Throughout the battery sagas, we have also discovered that the ‘Harmony’ and ‘Motorhome’ handbooks accompanying Bryony are not actually very user friendly. They can leave beginners feeling confused and rather ill-informed.

The ‘Harmony’ handbook, for example, clearly states that for winter storage you should shut down the EC700 unit. On the other hand, to use the ‘Harmony LOCATE’ app to monitor battery levels, you need to leave the EC700 on over winter. Meanwhile the Peugeot Boxer handbook suggests using the red battery isolator tab if you are leaving the MOHO in storage for any length of time (in doing so you lose the vehicle alarm). 

Everything appears contradictory because what the handbooks don’t tell you is that if you leave the EC700 unit on, the drain on the batteries is more than the 80w solar panel can cope with during the low sunshine winter months. The night time drain from tracker and alarm is more than is actually being replaced the following day. Similarly, the ‘Smart’ charging system where the batteries are charged on an alternating four-hour cycle, doesn’t help.  The upshot of all of this is that the Autosleeper’s Owners Forum is full of members facing this similar problem. Search for ‘EC700’ and there are over thirty pages of comments about the inefficiency of this ‘Sargant system’. Basically, leaving the system on and not disconnecting the vehicle battery leads to flat batteries.

The EC700 unit from Sargent

And this has now happened to us. We noticed the voltage on both batteries dropping rapidly over the course of last week. So, we thought we’d better go and check things out before the batteries closed themselves down and the alarms went off. We intended to start the engine and let it run in idle for around forty minutes. Not environmentally friendly and of no good to a Euro 6 diesel engine, but we had no choice. The storage site is closed to vehicles, so we can’t bring Bryony home. Not that we could anyway. We live on a very narrow road which has a bus route and there is no off-street parking available to us.

Predictably, the vehicle battery refused to start. Not even the dashboard screen instrument panel would light up. The app and ‘Harmony’ panel said both batteries were at 11.5 – 11.9v but the vehicle battery to all intents and purposes was flat! Yet, there were signs of electrical life. The habitation step extended and retracted, the interior lights worked and so did central locking. The ‘Harmony’ and ‘Truma’ panels lit up.  

Now before we go any further and attract criticism for making a non-essential journey, we feel we need to clarify a few things.

Firstly, we are in lock down and we have slavishly followed the rules throughout. However, the battery levels dropping so rapidly caused us alarm and so we looked up the rules about essential journeys. If you own a second home, you can make an essential journey for the maintenance of it. We have rightly, or wrongly, interpreted that rule as applying to motorhomes as well and so we made the short journey to the storage site. We didn’t meet anyone on the way there, whilst there or on the way back.

Second thing to clarify – the options available to us!

We are faced with certain constraints when it comes to battery management this particular winter:

1.   We can’t take the motorhome out of the storage compound. It is locked down

2.   There is no access to an EHU on the site

3.   We cannot get our car down to the Moho on site – see 1 above

4.   We could, by arrangement, get the RAC onto the site to charge up the battery but then that solves nothing and it is likely that the whole flat battery issue will happen again if lock down goes another month or more

5.   Our dealership is closed until the end of the lock down and are of no help at this time.  

Initially intimidated by all the wiring on top of the vehicle battery

Faced with a flat vehicle battery and a near flat leisure one, we decided to remove the vehicle battery and bring it home for charging. Having worked out how to safely remove the battery from YouTube videos and after getting over the initial shock of all the attached wiring on top of it, we then got another surprise. With the battery removed, the central locking wouldn’t work. We could lock the habitation and driver’s doors with keys, but not the passenger door.

Not wanting to leave the motorhome unlocked, we put the battery straight back in. You know what’s coming next don’t you!  The ‘Harmony’ panel showed both batteries at 11.8v and on the off chance, we decided to try the ignition again. Bryony started up immediately, at the first turn of the key. Go figure.  Now with an engine warning light permanently on, we ignored it and idled the engine for thirty minutes to get it up to temperature. The battery levels didn’t climb much, 12v, just.

We were faced with a dilemma.  Exactly what do we do? How bad was the vehicle battery? If we couldn’t take it out, what were our other options?

Two of the charts we found about leisure and vehicle batteries 

We turned to the various Autosleeper’s Owners forums for help and suggestions came thick and fast:

·        Hook up to EHU asap

·        Sort out the management system on the EC700 and ‘Harmony’ panel

·        Get the batteries home and charge them (although this then stops the tracker working)

·        Isolate the cab battery and lose the app reporting status

·        Don’t replace the vehicle battery until the management system was sorted or else it would happen again

·        Get the RAC out to charge up the vehicle and insist on taking it home to plug in the EHU

·        Do a modification to the solar panel charging system to improve it 

·        Use a lithium jump start battery and keep it in the Moho. Make sure it will start a diesel engine and cope with glow plugs

·        Disconnect both batteries after charging them up. Shut down Hab systems and isolate cab battery

·        Pull the battery fuse on the leisure battery and lift the -ve terminal on the vehicle battery

·        Reduce the power demands in the Moho by turning off all draining services and isolating the batteries

·        Sort out batteries and then take for weekly long drives

·        Check the voltage across the terminals to confirm ‘Harmony’ panel and app readings

·        Fit a battery isolator switch for next time 

·        Get a car down there and jump start it; turn on the car side lights and run the car for 15 minutes to put charge back into vehicle battery. Then turn off black button on EC700 unit and then connect up the jump leads to Moho and start engine. Don’t jump start a low battery because there might be a surge that fries other circuits

·        Use the red isolation button on the ignition barrel and then switch off the black button on the EC700; consumption will be minimal for both batteries and the tracker and alarm system should still work; the tracker gets its external supply from the leisure battery and will be unaffected by switching off the EC700. Don’t remove the leisure battery fuse as that forces the tracker to use its internal battery.   Turning off the EC700 will divert all solar charge to the vehicle battery. If the red isolator switch is used the battery won’t charge though. Central locking works for seven minutes after using the red isolator switch but if you use the key fob afterwards it will trigger the alarm so lock the doors using the key. Re-enter the vehicle using the key next time

·        Hire a 240v petrol generator for day, plug in EHU for a day with EC700 on smart charge

·        Read the ‘Harmony’ manual and understand it better

·        Do the EC700 mod using a Epever DuoRacer or Votronic MPPT controller

·        It may be a cell drying out and shorting so check the cells and fill any low cells with distilled water. 

It is clear that people think the manuals for the EC700 unit and ‘Harmony’ panel are vague in places, if not downright confusing at times. The EC700 unit consumes at least 300 mA when its on and less than 1 mA when it’s switched off, which goes mostly to the tracker. In the winter months the solar panel/regulator can’t provide enough current to power the EC700 when it’s on or to keep both batteries fully charged. Neither do the manuals tell you that when the EC700 is off all the solar charge goes to the vehicle battery but only if the red isolator switch isn’t used. The ‘Harmony’ manual implies that the alarm is powered by the leisure battery, which isn’t right it seems – it is the vehicle battery that powers it.

You can see why we, as newbies, have been confused and somewhat naïve.

 

Our leisure battery

Anyway, returning to our on-site dilemma, we managed to extract the vehicle battery, lock all the doors correctly (don’t ask) and bring the battery home. We purchased a Ring smart charger from Halford’s on the way; it has a seven-stage battery charge which includes de-sulphation through to reconditioning. Twelve hours later and the battery has gone back to 100% and 12.9v. (We have since put this battery back in Bryony with the red isolator switch enabled).

One day after the vehicle battery was removed, the app alerted us. The leisure battery alarm had been triggered and then shut off at 9v. Home it came. Rescued and charged back up to 13.4v, it was put back in last Tuesday. The EC700 unit was switched off. Since then, the battery has dropped 0.1v each day. It is currently at 12.8v after 6 days. At this rate we will need to recharge it up in a week’s time – so essentially, we will have to take the battery out, bring it home and recharge it every ten days or so.

 

As for the longer term, we have some decisions to make.

It would seem that most owners on the various forums have no problem going off grid for one or two days using the 80w solar panel during summer months, as long as they then have a couple of days on an EHU. We want to go off grid, wild camping, as often as we can in the future and especially on the continent. So, we need to consider whether we want to EHU every couple of days or sort things so we can go ‘wild’ for longer.

One option is to perform a modification that very many seem to have done. The Autosleeper’s Owners forum gives details of how to by-pass the EC700 unit so that the solar panel works more effectively in charging up the batteries. Not electrically technically minded, Steve is struggling to get his head around how it is done. Afterall there are nearly thirty pages of comments devoted to the EC700 on this forum.

The second option is to add another 80w panel up top (which eats into the payload but that is another story for another time) and then wire them up either in parallel or serial (still investigating which is best) and then by-pass the EC700 again. We don’t have room for a second leisure battery (which would be an ideal option). 

Our thinking is that if we go down this route then we need to get it done professionally so that it doesn’t void any motorhome warranties that we have on a new Moho. So now we are investigating the options and the budget implications.

Whichever way we go, taking electric bikes with us means that we need to either EHU regularly in order to charge them up; or sort out the 12v power systems onboard and add in an inverter of some form.

What a steep learning curve this motorhome malarkey is. As always, if you are an experienced motorhome owner and have any tips or advice that might help, then please do share them in the comment box below, so that we newbies can learn and progress further. If you want to drop us a postcard – a picture of you and your motorhome – we will add it to our ‘Postcards from….’ Page.

In the meantime, stay safe and well in these strange times, enjoy your motorhome, wherever it may be at the moment and remember, ‘take care out there’.

Steve and Maggie

PS: ‘You don’t know what you don’t know’. 

We have since discovered via those good people on the Autosleeper’s Owners Forum that the 13.4v charge on the leisure battery is in fact a false reading. The battery will, apparently, always show this when it has been charged. The actual real voltage of a full battery is nearer 12.7v and this is what the leisure battery has been at every day since we reinstalled it. Which is fantastic news, because it means the battery has held its charge and is not running down. Phew – that’s a relief.

PS PS:

We were referred to this very  interesting website - worth a read if you are struggling with your batteries, the EC700 and an 80w solar panel up top

http://www.aandncaravanservices.co.uk/sargent.php