12V Three Way Fridge Problem

[carsphil2]

Hi ,ive just gone down that road "NO 12 VOLT POWER SUPPLY TO MY FRIDGE" after many hours tracing the wires from the fridge to the zig unit ,and then to 2 relays under the bonnet 1 of which was for the spltcharging of the leisure battery and the other is for the 12 volt supply for the fridge both of which are linked via the 12 volt supply from the alternator ,meaning the 12volt supply on my m,h is only available when the engine is running , it turned out that BOTH relays where at fault having NO power coming out of them at all 8o| , meaning i had no splitcharging for the leisure battery something i wasn't aware of ,as on site or at home the 240v was always connected and topping up the leisure battery so i would'nt have noticed now having replaced both relays (and got a spare just in case ;-) ) for £11.46 for all 3 and i now have power for both fridge and split charging the only reason i can think of for BOTH relays giving up is 1 of them packed and all the load was put onto the remaing 1 taking that out aswell in time , my m,h is a TALBOT EXPRESS ELDDIS AUTOSTRATUS "1990" SIXTEEN YEARS YOUNG i imagin the age of the relays would also have played a part in them packing up , just so i can check if the 12volt supply is reaching the fridge i have fitted a small led and a little microswitch push button on the zig panel so whilst the engine is running if the button is pressed the led will iluminate indicating a 12volt feed is present , as my fridge is an ELECTROLUX RM212F with NO led to indicate that power is present . hope this may be of help to others phil

[dustyduetto]

Ok my bit on 12v fridge. The theory is that unless the vans engine is running the fridge won't work - not strictly true with my van as the ignition only needs to be on for the fridge to draw current. This in itself might be an issue with a not very good starter battery so make sure that the engine has been started not just ignition on. On a second fridge issue I have a dometic RM6271 which has no indicator lights for 12v 240v service. Gas is easier to check and the clicker goes out when gas ignites and comes back on if the gas runs out or gets blown out etc. Has anybody ever fitted led indicators to this fridge and if so what are the issues.

[Derek Uzzell]

Dustyduetto: It should be a simple and uncontroversial task to add an LED to your fridge to indicate 12V operation, but I'm not sure about the 240V side. (Perhaps Clive can comment?) You'll see from my posting of 18/7 that my Herald's fridge's 12V supply was also energised when the ignition was switched on but prior to the motor starting. As you rightly say, this arrangement may have an adverse impact on engine-starting. Pilote's Owners' Handbook used to say "Switch refrigerator to 12V power as soon as the motorhome's engine is running" but I doubt if anyone followed this procedure.