three way fridge wiring

dingo · Member

three way fridge wiring

PeterS · Senior Member

Dingo, somewhere on this forum just a week or so back there was a long discussion on fridge wiring, Use the search at top of page and I am sure you will find it. Had heaps of info on it. 3way fridge should be wired to start battery and only power fridge while engine is running, Its all in that thread.

Peter

jimricho · Guru

A relay is a good idea otherwise you have to remember to switch the fridge off when stopped. As PeterS points out the fridge should be wired to the start battery and not the house or auxiliary battery.

An alternative to installing the relay is to install a "Fridge Switch" http://www.rvelectronics.com.au/page.asp?parentid=3&parent2id=14 This has the advantage that it can be installed by those with limited handyman or technical skills.

If you click on this link I think this is the thread that Peter is referring to http://thegreynomads.activeboard.com/t47789434/12-volt-fridge/

Jim

landy · Guru

As already said a relay activated from the ignition circuit is a good idea, and is what I have done. Having said that I am led to believe that a lot of the new automatic fridges are voltage sensertive and will only run on 12 volt when the car alternater is charging. Only hear say.

Landy

-- Edited by landy on Thursday 15th of March 2012 10:16:30 PM

PeterS · Senior Member

I have one of those new fangle auto fridges in my MH that I don't fully understand as I havnt used it yet. What I have been told and read in the manual when on auto it selects the most suitable power sorce. ie: if it cant find 240v it goes to 12v if neither avail it lights itself on LPG,Pretty clever hey! I do know that if driving its on 12v and if you turn of engine it automaticly lights the gas, not sure yet if it turns gas off and goes back to 12v on its own when engine restated, I think it's supposed to. will let you know after first shakedown run sometime in April

PS: this does mean that the LPG bottle must be turned on for it to work.

-- Edited by PeterS on Friday 16th of March 2012 08:19:08 AM

oldtrack123 · Guru

Hi

Jusy to clarify

The AES [automatic energy selection]fridges require TWO seperates sources of12v

[1] A direct feed from the tug battery for the heater section [HEAVY CABLES]

Depending on actual fridge model this may or may not requires an ignition or voltage controlled isolator[VSR]

Some models have this inbuilt into the fridge

[2] A seperate permanent 12v supply is required for the control system

This requires light cables from the VAN battery

These models select the energy source in the following sequence

first 240v

second 12v

third gas

if on gas & either 12v or 240v become availalable they will revert to that source

Jim's point about turning the gas Off with vans such as his is very valid

The switch from 12v to gas does have a time delay for short stops such as refueling ,but my preferance would be to turn the gas off

Like any absorpation fridge, they can be damaged by running out of level this is quite possible when not actualy setting up to stay[such as extended shopping times /sight seeing]

Peter

-- Edited by oldtrack123 on Friday 16th of March 2012 11:03:49 AM

jimricho · Guru

Maybe I should have been clearer in my previous post, the word "you" was intended to be interpreted in the third person, maybe I should have said "one".

I was endorsing the installation of the relay as you had noted and I did this, and mentioned the Fridge Switch, for the benefit of others coming to this thread. It's been my experience that many installations do not have this relay installed and I'm aware of more than one instance of a flat battery as a consequence. In one case a friend of mine ended up replacing his battery (he did not give details such as battery age etc) and had his travel plans considerably inconvenienced.

I can't help with the newer automatic fridges as I don't know much about these.

I have a voltage booster installed in my fridge circuit that delivers 14 volts to the fridge element.

jimricho · Guru

PeterS wrote:
I have one of those new fangle auto fridges in my MH that I don't fully understand as I havnt used it yet. What I have been told and read in the manual when on auto it selects the most suitable power sorce. ie: if it cant find 240v it goes to 12v if neither avail it lights itself on LPG,Pretty clever hey! I do know that if driving its on 12v and if you turn of engine it automaticly lights the gas, not sure yet if it turns gas off and goes back to 12v on its own when engine restated, I think it's supposed to. will let you know after first shakedown run sometime in April
PS: this does mean that the LPG bottle must be turned on for it to work.

-- Edited by PeterS on Friday 16th of March 2012 08:19:08 AM

If this is so one would need to make doubly sure the gas is turned off when travelling (as it should be anyway) to avoid the possibility of it operating on gas when it shouldn't.

In rigs like mine (see avatar) that would apply anytime the roof is down.

The auto 240v/12v changeover would be a handy feature.

PeterS · Senior Member

Thanks for those tips oldtrack and Jim I must admit that the idea of leaving the gas turned on while traveling did worry me a bit but as I said I havnt traveled in it as yet. Good advise all round tho.

Peter

PeterD · Guru

Here is a ink to a page on how AES fridges work http://www.rvmobile.com/tech/trouble/aes.htm

This link gives you a link to a Dometic training manal that coveres 3 generations of models - http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&sqi=2&ved=0CEEQFjAC&url=http%3A%2F%2Fgasrefrigeration.net%2Fdom_techdata%2FAES_SM.PDF&ei=k2djT5OuHqOViQec6ZTIBQ&usg=AFQjCNHzKxTi2e90j57lHQyo5JAdoZQOUQ&sig2=9oXm8pUt3xLiQVZkjaTtmg

-- Edited by PeterD on Saturday 17th of March 2012 03:29:29 AM

-- Edited by PeterD on Saturday 17th of March 2012 03:39:10 AM