What does this switch do ?

I have a switch in my Cotswold that is on the outside of one the the side lockers, immediately behind the switch is the leisure battery and this switch has wires that connect to the battery.

This switch is mounted immediately below a 240 V socket but it has nothing to do with the socket.

There is an amber light on the switch that will illuminate whether or not the motorhomes 12V electrics are switched on or not.

If the switch is on and the amber light is on, the battery current on the display reads around 10A, if the switch is off then the battery current drops to around 7.7A.   There is no 240V mains connected to the motorhome.

I can find no reference to this switch and its function in the handbook.

Is this switch something to do with the solar panel ?

A bypass switch for the cab radio?

Hi Peter, thank you for the suggestion.  But I have just checked and the switch has no effect on the radio.

Anything to do with fresh water tank heater ?

Hi Quilter, that’s an interesting suggestion, however, I am not aware that there is a fresh water tank heater and I can find no reference to one being fitted on my Cotswold.
Surely if there was such a heater fitted, it would require the the main 12V switch on the panel to be on ?  The amber neon on this switch will illuminate even when the main 12V switch on the display panel is off.

They do operate on 12v, but should not be used without EHU, as they will drain your battery in no time.

Sorry Ploughlin but what are you referring to ?  I guess it is the fresh water tank heater, but I am sure that I do not have one, and I agree they would cause a high battery drain if used off grid.

I cannot see any reference to one either on the Cotwold’s electrical wiring diagram so I really don’t believe that switch is for that purpose.

Could it be the switch for the external ( awning ) light ?

No that’s on the Aux button on the main Control Panel.

Is it worth asking AS ? In our experience they are very helpful when it comes to this sort of query. Assuming that is that it is fitted by them and not retro- fitted by a previous owner or their dealer.

Seastones

I would say it was fitted by the previous owner.
You say that it is connected to the battery are their any cables from the switch going to some equipment in the van, if not I would disconnect it from the battery to avoid it being switched on and draining your battery.

I think that it was factory fitted because the switch and socket above it are of the same style used through out the motorhome.

Dickie9 thank you for your interest but if I knew what equipment was being fed by the wiring/switch I would not be asking this question.

I am not sure how to post an image to this forum but I will provide a link below of the switch and hopefully it will upload.

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Seastones wrote:I think that it was factory fitted because the switch and socket above it are of the same style used through out the motorhome.

Not necessarily. We bought 2 of the same 240V sockets, from AS, and had them fitted - one in the same place by the look of it. They keep them in stock at Willersey.

Just my opinion so possibly completely wrong!!

The fact it is wired direct to the battery would indicate an aftermarket connection IMO, the close proximity of the switch to the battery would back this up as it would be convenient to fit close by. That style of socket is also readily available so don’t let that mislead you.
Tracing the wires (however tricky that may be) would be my next step.

That style of switch and socket are standard CBE items and can be bought from virtually any caravan accessory shop. I have just fitted a couple, to work the washroom lights (who on earth thinks it is reasonable to operate a 10mm diameter light switch on the ceiling?) and to work one of the reading lights above the bed.
If you want to know if you have under floor heated tanks just lie down on the ground and look up at the underside of the water tanks. If they are heated there will be a rectangular pad with a 'heated tank' label and some wires coming from it.
I am very disappointed in the quality of switch labels in the A/S, they peel off before you have memorised what they do, so I am trying to stick mine in place with some good adhesive which doesn't squelch out the edges.

Thanks gassygassy,  I shall look under the M/H in the morning.   I would be happy to find heaters under the tanks, this could potentially be very useful.    

Switching this switch on causes a drain of about 2.5 amps so it could be something like this, probably not something to use when off grid, but only when on a hook up.

I'm tempted to go out now, it's nearly 10pm, but I will resist until the morning.

I'll let you know

Seastones wrote:
Switching this switch on causes a drain of about 2.5 amps so it could be something like this, probably not something to use when off grid, but only when on a hook up.

If you find you do have tank heaters then can I suggest you make yourself a laminated notice to hang on your steering wheel to remind you to switch it off after use. We’ve never used ours, even at temperatures well below zero on the high Spanish plains in winter, but can just imagine ourselves leaving them switched on.

I had another couple of thoughts.
Firstly I think it must be an amateur after-fitment, if you get my meaning. Those CBE switches and sockets are separate units fitted into a frame which is then fixed to the wood panel. A professional fitting a 13A socket and a switch wouldn't put the switch below the socket because when you plug something into the socket firstly you would obliterate the switch with the wire, and secondly you might switch the switch on or off with the mains wire or the back of your hand. You can very easily ping off the plastic frame, unscrew the two CBE modules and refit them with the switch over the 13A socket, as it should have been done in the first place.
Secondly if it were a water tank heater, AutoSleepers would have labelled it. Having said that, the labels on mine while nice and neat labels are peeling off because the adhesive they use is rubbish. I need to find a quality adhesive to stick them on with. Very oddly I have one tank heater switch above the entrance door and the other tank heater switch in the offside bed box. I have no intention of using either of them. I have some unidentified fuses next to the leisure battery and near one of the aforementioned switches so I'll have to find out what they are for.

gassygassy wrote:
Secondly if it were a water tank heater, AutoSleepers would have labelled it. Having said that, the labels on mine while nice and neat labels are peeling off because the adhesive they use is rubbish. I need to find a quality adhesive to stick them on with. 

We have no labels on any of our sockets or switches ( 2014 Broadway, bought new). I didn’t know they existed. 

Our tank heaters came as part of the semi- optional Winter Package which also included 6kW rather than 4kW Truma Combi heater, cab blinds not curtains and insulation over the internal wheel arches. Does the OP have these features ? 

Our last van ( not AS) had, from new, a bank of 3 vertical sockets in the kitchen area,neatly aligned one above the other, so that only the top and bottom one could be used for the reasons you give. Easily changed so the sockets were sideways on but we used to wonder which apprentice was responsible for the original.

Oh, seems that I have got the semi-optional Winter Package as I have all those things you listed. Note that when you take it for a part exchange value they ignore all accessories and optional packages, they just assume whatever you have got is the basic version.

gassygassy wrote:Oh, seems that I have got the semi-optional Winter Package as I have all those things you listed. 

My OH tells me that the switch for our tank heater is under the driver’s side bench, on the wardrobe wall - not labelled in any way.

I wonder if the switch that the OP has was either retro-fitted by a previous owner or their dealer to avoid having to lift the heavy bench cushions to turn the heater on ?  There seems to be a small neon light which is useful to remind you they are on.

OK, I've managed to follow one of your suggestions and trace the wire from the switch to its destination.      Squeezing myself under the van is no fun but I have traced the wire from the switch, through a hole in the floor, along the underside of the van and to a device that is mounted low down in the fresh water tank.

This device has two brown cables leading from it, and these brown cables change to black cables via a terminal connector block.  So, one black cable goes back to the switch then on to the positive connector of the battery (there is an in-line fuse between the switch and the battery), the other brown/black cable from this device connects directly to the negative terminal of the battery, which forms the circuit.

I didn't know that I had such a thing but I have to assume that this device is indeed a heater on the fresh water tank.  Which in certain circumstance may come in useful.   However, it's odd though that the tank may be heated and frost protected in severe weather but the plastic pipes to the taps are not lagged and are potentially vulnerable to freezing, so perhaps that is a job for another day.

I have taken a photo of the device, this can be seen by clicking on the link below :-

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Ever since I have owned this motorhome I have been puzzled by this switch, so hopefully I can now sleep peacefully in the knowledge that I now know what it is for.

Thank you to everybody who took interest in this on my behalf.

Looks like you have an In-tank probe heater like that shown on CAK Tanks top of page 20. [You must be registered and logged in to see this link.] 30W consuming 2.5A.

Hi Ploughlin,  yes it does like that one.   I said further up this thread that it consumed 2.5A so this must be it.

Now we have identified what the switch does and what it controls, how do these work ?

Are they simply switched on and a thermostat cuts the heater on and off when a certain predetermined temperature is achieved, rather a tropical fish tank heater   Or is it up to the user to turn them on and off when it is felt that a bit of heat in the tank would stop them from freezing up ?

Don't know really. The CAK pages shows a manual one and an automatic. I presume the manual is always on when switched, the automatic probably with a thermostat. Which you have ?

If when switched on it always shows 2.5A use then it is probably constant heating.