testing fridge on 12V

[DavidPallister]

Evening all

Got an Electrolux RM212 fridge in my mums garage that I'm hopefully going to be selling shortly, it's been sitting unused for a few years so want to test it 1st.

We only ever used it on gas, so I know that works.
For 240V testing, it can be plugged straight into the mains, but to test the 12V, putting it straight onto a battery would flatten it in no time, so can I attach a charger to the battery and run the fridge at the same time (fused of course)?

Cheers

Dave

[filbay]

Hi, I don,t know the answer , but may be interested in buying it when you decide to sell ? Cheers........

[pirate-pete]

Why not put the battery on it and if it does run the battery down in a few hours then it is working? There are no moving parts so any power used up must be heating the element no different than if fridge on other sources. Then use your charger to charge the battery back.

Typical fridge will probably draw 8 Amps on 12V depending on rating of element. Should get a few hours at least out of the battery depending on the charge. In theory an 80Ah battery would run 8A for 10 hours. Would have thought you could test if fridge working in less time than that.

Back to the original question I'd be happy putting my charger in line with battery like you say but my charger is an old one that has had a fair bit of abuse as a power supply to test 12V kit! Doubt I would do the same if it was an expensive smart charger.

[ghost123uk]

pirate-pete is 90% correct there ^^^

If it draws power off the 12Volt (and it cools OK when on mains) then it must be working.

I only popped in to say, don't hook it up to a battery and test it to the point where the battery has gone flat. Doing that quickly knackers batteries. Anything below 11.5 Volts is bad for them.

I note that mine takes an hour or more on 12 Volts before you can noticeably feel it getting cold. Mind you, the stat on mine must be dodgy as I have been known to wake up needing some nice cold breakfast cereal, only to discover the milk is frozen solid

[Ralf85]

Mind you, the stat on mine must be dodgy as I have been known to wake up needing some nice cold breakfast cereal, only to discover the milk is frozen solid

My temp control is overridden and will freeze milk under normal temperatures. So unless it is very hot I switch my fridge off overnight to stop things freezing - et voila!

[ghost123uk]

Mind you, the stat on mine must be dodgy as I have been known to wake up needing some nice cold breakfast cereal, only to discover the milk is frozen solid

My temp control is overridden and will freeze milk under normal temperatures. So unless it is very hot I switch my fridge off overnight to stop things freezing - et voila!

Aye, the next time I have my fridge out for any reason, I will check the temp control.
btw, is it a stat or just a flame size adjustment ?

[Ralf85]

Put a thermometer in the fridge close the door. Check the temperature after 15 mins. Then hook it up to the battery and check the temperature change after an hour. The temperature should have gone down several degrees by then. If it has, then job done. No need to flatten the battery. Simples!

[DavidPallister]

Thanks everyone, I'll try and test it sometime during the next week.

Filbay, if all is good i'll let you know and you can have 1st refusal

Dave

[AdrianC]

If it draws power off the 12Volt (and it cools OK when on mains) then it must be working.

^ What he said. The actual coolant circuit is the same between all three power sources. The only difference is the heat source. If it tests for continuity across the element, and sucks power when you connect it, it'll chill on 12v if it chills on either/both of the other two.

There's no reason why it won't work off a BIG ENOUGH battery charger. IIRC it's a 75w element, which is 6-and-a-bit amp.

[DavidPallister]

I'll check continuity across the element then, and put my (10 amp) ammeter in line with it briefly and check it draws current.