Voltage needed for fridge?

[chriscburgess]

Have just come back from a beautiful weekend at Burnham Deepdale campsite in Norfolk.

Charged both batteries before we went.

Cooled fridge on 240v before we went then used 12v for 3 hour journey. Nice and cold on arrival.

Switched to gas when we got there. Nice and cold for about day and a half. Switched off gas when we went out in van for the day and turned to 12v.

On returning ignitor would not spark to reignite the gas side. Leisure battery said it 12.4 volts. So without fridge for about 24 hours.

Now returned home after 3 hour journey and the ignitor sparks. Checked battery and it is at 12.6 volts.

so my question is what voltage does the ignitor need to spark? and given the leisure battery only operates the fridge why would it drop to a level that it does not seem to work?

Thanks
Chris

[MidLifeCrisis]

Those ignitors are pretty 'voltage tolerant' I think - I'm sure the RM212 fridge manual suggests that in an 'emergency' you can use a 9v battery connected to that ignitor to get a spark - so I doubt a few tenths of a volt would make a difference!

I think your problem may be somewhere else? Maybe a loose connection?
Note that the 12v supply to the ignitor is different to the 12v supply when the fridge is run on 12v (or it should be at least!) So check that the ignitor 12v supply to good?

[ninja.turtle007]

How did you turn off the gas? If you just pushed the 12v switch the gas will still be lit, hence why no spark. I learnt this from experience.

[Oldiebut goodie]

I am sure that I read a post a while back that the gas will not ignite immediately after running on 12v, it needs to be left for a short while. I don't know how true that is as I never use 12v and run on gas continuously. (I prefer to have a charged battery, sounds like you could do with using your charging for the battery rather than the fridge as the leisure was only 12.4v after a run - should have been around 13v if you measured it straight after being charged)

[Ian Hulley]

I am sure that I read a post a while back that the gas will not ignite immediately after running on 12v, it needs to be left for a short while. I don't know how true that is as I never use 12v and run on gas continuously.

Morning Mr OBG, all I can say is that we do it with our's all the time ... fridge on 12v while driving, straight onto gas when we stop ... ignites straight away, no problems.

Cheers, Ian.

[Oldiebut goodie]

That post was a couple of years ago so there isn't much chance of finding it again.

[chriscburgess]

How did you turn off the gas? If you just pushed the 12v switch the gas will still be lit, hence why no spark. I learnt this from experience.

I just use the switches on the front of the fridge to switch between gas and 12 v(whilst driving). Have never actually turned the gas off on the stopcock thingy as i thought by switching to 12v this will switch off the flow of gas anyway. is this not the case?

Anyway if the gas was still lit the fridge would be cooling which it was not.

[chriscburgess]

I am sure that I read a post a while back that the gas will not ignite immediately after running on 12v, it needs to be left for a short while. I don't know how true that is as I never use 12v and run on gas continuously. (I prefer to have a charged battery, sounds like you could do with using your charging for the battery rather than the fridge as the leisure was only 12.4v after a run - should have been around 13v if you measured it straight after being charged)

so after 3 hours of driving the leisure battery was at 12.6 v. Should it have been more? if so does that indicate a problem with the alternator? I did have new regulator installed about 10,000 ,miles ago

[Oldiebut goodie]

I would expect to see more like 13v if it were checked immediately after 3 hours charging - it will slowly drop to the fully charged state of 12.7v after standing for an hour or so. I would check to see what voltage the alternator is charging at as it may be low. Also the charging wiring may not be optimum, undersized cable/dodgy joins/connections/etc

(I was losing 0.2v on the alternator to battery charge cable due to corrosion in a crimped terminal so you can see how losses can soon mount up. If you have 4 connections to the leisure battery with a split relay and had that loss, 0.8v, and a 0.1v loss due to voltage drop in the cable you have lost, rounded up, 1v which will make quite a difference to your charging)

The 12.6v is ok - it was the 12.4v that sets the alarm bells ringing and led me to saying that I would prefer to charge my batteries rather than run the fridge on 12v.

[chriscburgess]

Thanks OBG thats really helpful. I'll do some detailed research on the condition of wiring ect and replace what i can if necessary and check the alternator.