fridge fan wiring

mfexpanda

Well-Known Member
Apr 1, 2011
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Brookfield, Vic
Guys
I just installed a Dometic Ventilator kit, thats what the box calls it, Its a 12v fan thermostat and wiring .
But I have found a few things out while doing it.

1 We have a 150ltr fridge and there's no way I can install it the way they show without pulling the fridge out, and that aint going to happen.
They want you to mount fan between absorption unit and condenser and as near to the absorption unit as possible, just cant get in there through the bottom vent.
So I mounted it to the top vent so it sucks up the heat and blows it out the top vent.

2 I have only a 7 pin plug fitted , the anderson plug is getting fitted this weekend, so jayco ran the 12v from the fridge and piggybacked it to the power pin on the 7 pin plug [ normaly rev lights] which also normaly feeds the the 12v needs inside the van.
the problem is as I see it the 12v side of the fridge will only get power from the car, be it through 7pin or anderson plug, and not from the setec unit.
So if we are connected to 240v and using the setec the fan can not work .

3 The only way I can see the fan working is to connect it directly to the setec unit
 

grinner914

Member
Aug 3, 2011
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Bacchus Marsh VIC
Is there a 12 volt socket or other 12v appliance nearby that you get piggy back 12v from?
The 3 way fridges draw a lot of current when on 12 volts (8 or 9 amps), and would quickly flatten the van battery or overload the sectec unit.

My theory in my Eagle, was to only have the fridge running from 12v when connectted to the car, when the engine was running.

I did this via a 12 volt cable running from the car battery, via a relay which only activated with the ignition, which went to an anderson plug at the back of the car. The anderson plug on the camper plugged int to this, which was wired straight to the fridge, and only to the fridge. This way the only way I could flatten a battery was if I left the car ignition on without the engine running.

Having done all this, it was a pain to get into the camper when it was wound down, to switch the fridge to 12volt, so probably more often than not it travelled with no power to the fridge at all, it still stayed cold! It may have been at 0 or 1 degrees when we packed up, after a day of travelling it may have risen to 4 or 5 dergrees

One trick we found was to keep some esky freezer blocks in the freezer all the time. I think this managed to maintain the temp in the fridge.

I had the new Expanda fitted with an anderson plug to the drawbar, but I still haven't had a chance to work out what it is connectted to in the van.

Jason
 

boots33

Well-Known Member
Jun 25, 2011
708
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Maudsland Gold Coast Hinterland Qld
the problem is as I see it the 12v side of the fridge will only get power from the car, be it through 7pin or anderson plug, and not from the setec unit.
So if we are connected to 240v and using the setec the fan can not work .

3 The only way I can see the fan working is to connect it directly to the setec unit

Yes that is correct the fridge will only get 12v from the car so there will be no power on that circuit when the car is not plugged in. the same goes for the charge wire on pin2 as the setec unit will block the power coming back from the van battery. I have not had any experience with the fan unit you have but if it requires a permanent battery supply you will be best to hook it up to the van battery direct (with a fuse). I know chartrock has a fan in his and also has it hooked up through a toggle switch so he can turn it off if needed.
 

Bushman

Forum Moderator
Staff member
Nov 9, 2010
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Wollondilly Shire NSW
I have the fan with the 150 ltre fridge (dealer fitted fan) from memory it mounted in top vent and the thermosat is attached to one of the pipes, I 'm not even sure if it works, not sure were the power comes from either can try and have a look if you like, I would have prefered it to have a switch as well, like my camper had, but it doesn't
 

richard

New Member
Jun 9, 2011
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Getting a little confused here with stuff. I think my questions sort of rolls of this topic so will post it here and feel free to move it if you need to.

The basic questions are ...

1. Does anyone run the fridge off the battery on DC? If so how long does the battery hold out for?

2. My fridge as I understand runs off the anderson plug whilst travelling and connected to my vehicle. (on DC) Will it still run on DC without being plugged into the tow vehicle?

I know that the fridge would pull a lot of amps if just running from the battery, but am wondering if mine is actually doing that or not. Is there a way I can find out and if anyone has this sort of set up.

Some additional info that may be of help in this discussion - I have a standard 7 pin plug and then an anderson plug. When plugged into the anderson plug with the car running, the reading at the battery reads approx 14.46 volts. I can also take a reading from the anderson plug at the front of the camper when not plugged in to read the volts on the battery. (For some reason this works when lights are on, but if the fridge is on DC, then there is no reading.)

Anyway if anyone can help out on this - feel free to ask questions etc, just trying to figure out how it is all wired up so I can make the right choices when we go travelling.
 

cruza driver

Hercules
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Nov 9, 2010
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Mighty Victoria
Getting a little confused here with stuff. I think my questions sort of rolls of this topic so will post it here and feel free to move it if you need to.

The basic questions are ...

1. Does anyone run the fridge off the battery on DC? If so how long does the battery hold out for?
No we dont so sorry I cant answer that one we usually just have the fridge off whilst travelling

2. My fridge as I understand runs off the anderson plug whilst travelling and connected to my vehicle. (on DC) Will it still run on DC without being plugged into the tow vehicle?
It normally only gets power via the trailer plug as the anderson plug only charges the battery Unless your van has been rewired

I know that the fridge would pull a lot of amps if just running from the battery, but am wondering if mine is actually doing that or not. Is there a way I can find out and if anyone has this sort of set up.

Some additional info that may be of help in this discussion - I have a standard 7 pin plug and then an anderson plug. When plugged into the anderson plug with the car running, the reading at the battery reads approx 14.46 volts. I can also take a reading from the anderson plug at the front of the camper when not plugged in to read the volts on the battery. (For some reason this works when lights are on, but if the fridge is on DC, then there is no reading.)

Anyway if anyone can help out on this - feel free to ask questions etc, just trying to figure out how it is all wired up so I can make the right choices when we go travelling.
 

Matty4

Well-Known Member
Mar 18, 2011
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Wandin North, Vic
My understanding is that the fridge will only run on 12v if connected to a vehicle through the hotwire in the 7 or 12 pin plug. It will not run on 12v from the van battery.
I only have the 12 pin plug and the hotwire to run the fridge and charge the battery runs through that. Trying to run the fridge off the van battery would be pointless as it will not be able to cool the fridge down, it just helps to maintain the temp whilst travelling. If you don't have access to 240v then running the fridge on LPG is your only real option. It actually works rather efficiently on LPG too!!

Cheers,
Matty
 

richard

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Jun 9, 2011
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Thanks for the responses guys - probably best to run off gas then. Just thought for the quick overnight stop it might be easier.

Will have to see what it does on a long trip when connected to the tow vehicle.
 

Ben

New Member
Aug 22, 2011
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Mandurah, WA
I am going to have the same setup as you Richard in regards to the 7 pin and anderson plug. I too was hoping that the fridge will run of the van battery which is getting charged via anderson plug. I have the auxiliary battery in my tow vehicle and with the van battery also a combined 170 amp/ hour. The 184 liter fridge will draw around 18 amp/hour on 12volt.
Since mine is still getting built would I be able to request this from the dealer and are there any issues with this setup?

Cheers Ben
 

cruza driver

Hercules
Staff member
Nov 9, 2010
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Thanks for the responses guys - probably best to run off gas then. Just thought for the quick overnight stop it might be easier.

Will have to see what it does on a long trip when connected to the tow vehicle.
With a quick overnighter its just as easy to flick it on gas plus as Matty4 said 12 volt will only maintain temp not cool the fridge down.
 

richard

New Member
Jun 9, 2011
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I am going to have the same setup as you Richard in regards to the 7 pin and anderson plug. I too was hoping that the fridge will run of the van battery which is getting charged via anderson plug. I have the auxiliary battery in my tow vehicle and with the van battery also a combined 170 amp/ hour. The 184 liter fridge will draw around 18 amp/hour on 12volt.
Since mine is still getting built would I be able to request this from the dealer and are there any issues with this setup?

Cheers Ben

I would not see a problem with getting them to wire it so you can use the battery to run the fridge. I suppose that I just think that if you are only stopping overnight why waste the gas when you have the battery for free and can charge it again when you get back on the road the next day.
 

Ben

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Aug 22, 2011
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Mandurah, WA
My main reason for this is say you're doing a 8 hour drive, (4hours then rest for a few hours and then another 4 hours driving) which is pretty common for us while travelling. If the hotwire through the 7 pin is supplying the van's fridge and this is the only supply, then when the ignition is switched of there will be no power to it, or does it switch over to the van battery at this stage. Like Matty has said you could just switch the fridge to gas for extended periods but for a few hours you would think the battery could be utilized.
 

Matty4

Well-Known Member
Mar 18, 2011
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Personally, for the extra expense of having Jayco alter the wiring to allow you to run the fridge off the battery for a few hours, you would be better off just using the gas. It takes no more than 20 seconds to flick it over and then you have the ability to keep the insides cool.

Lets face it, if you are stopped for a few hours on the side of the road then you most likely will be accessing the fridge several times for food and drinks etc, and everytime you open the door you alter the temp inside. The fridge on 12v will not bring it back down again, only maintain it. Therefore you are better off using the gas. Switch it back to 12v before driving off when you won't be opening and closing the fridge door and all will be fine.

I can't imagine the fridge using a lot of gas. I ran our fridge and HWS on gas for 12days straight (no access to 240v on the Gibb River Road) and used about 1/2 a 9kg bottle.
 

PMK

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Jul 25, 2011
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Sunbury Victoria
I have the hot wire for the fridge on my trailer socket wired to my unswitched Auxillary battery in my car. (not the cranking battery) I also have the battery in the van via an anderson plug connected to the Aux battery in the car (to charge while travelling)
I have the fridge on DC when travelling & it works well. For the short time I would be stopped in a trip the fridge runs on both the Aux battery in the car coupled to the battery in the van via the anderson plug. This gives me a total of about 200ah capacity which easilly runs the fridge for a short stop. We have stopped for a couple of hours on occasion & not had a problem.
Note the Aux battery in the car is not switched off when the ignition is.
Having said this I always use the gas when camping without mains power. The batteries won't run these fridges overnight.
Hope I haven't confused anybody.............. beacuse I think I've confused myself now !!

Paul PMK
 

richard

New Member
Jun 9, 2011
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I can't imagine the fridge using a lot of gas. I ran our fridge and HWS on gas for 12days straight (no access to 240v on the Gibb River Road) and used about 1/2 a 9kg bottle.

Thanks for the info on the amount of gas used for the fridge. I thought it may go through a bit more than this, but it seems rather efficient then on gas.
 

Ben

New Member
Aug 22, 2011
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Mandurah, WA
Paul,

Do you have the 12 pin or the 7 pin, I thought that when we ordered the van they said that you need to have the 12 pin for the bigger hotwire to run the fridge. The setup you have is identical to mine except the hotwire going through the plug, I'm sure that Jayco can split of the anderson plug to supply the fridge and charge the van battery. I also have a engel in my car so was going to leave the anderson plug hooked to the car when free camping and have a second anderson plug on the van (just tee it of) and this way I can utilize my portable solar to charge the vans battery and my cars auxiliary battery. Just trying to keep the car the same and modify the van as the tug is setup for the boat.

Thanks Ben
 

PMK

New Member
Jul 25, 2011
194
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Sunbury Victoria
Paul,

Do you have the 12 pin or the 7 pin, I thought that when we ordered the van they said that you need to have the 12 pin for the bigger hotwire to run the fridge. The setup you have is identical to mine except the hotwire going through the plug, I'm sure that Jayco can split of the anderson plug to supply the fridge and charge the van battery. I also have a engel in my car so was going to leave the anderson plug hooked to the car when free camping and have a second anderson plug on the van (just tee it of) and this way I can utilize my portable solar to charge the vans battery and my cars auxiliary battery. Just trying to keep the car the same and modify the van as the tug is setup for the boat.

Thanks Ben

Hi Ben,
I currently have a 7 pin plug (on my Eagle, waiting for my expanda in Nov) But the idea is the same. When I get the expanda it will have the 12 pin plug for the larger fridge. I will need to change the socket on the back of my car to a 12 pin then. I will hot wire the supply to pin 12 direct from my Auxillary battery in the car. Same system I am using now.
PS: I also have the engel "Tee off" connection in the car.
With the new van the two batteries (Car Aux & Van) will still be coupled & charging when towing. & supply the fridge when stopped for a short time.

Paul

PS; All these runs from the batteries need to be fused........ Thought I should mention that !!