Engel old style

Thanks for the info Ken.

You can buy a kit from Jaycar to do what you want. A bit of soldering required but have used them before

Part number is KC5463 can output up to 15v at up to 4 amps

Thanks Tom $17 from Jaycar
Ian

Ian, I doubt that kit will work.
Need a Rectifier because the Engel compressor is 21V AC not DC.
See my post below for the kit we used years ago.

Any simple 3 terminal regulator kit will do the job....adding a rectifier is a non issue.

Ive been running fans off similar regulator kits for ages...there are some more suited kits that have the option of rectifiers on board..and you only need a 1 amp regulator.

for that matter..there are a number of other ways of doing this.

1. fit a 24 Volt fan with a series diode or a full rectifier.
2. bring 12 volt supply from the inlet socket direct to the fan

here are some options to think about.
even if running direct off the 12 volt input......run a 24 volt fan.....it will happily run at half speed and be a hell of a lot quieter.

regardless of the source of supply, run a variable voltage regulator to vary the speed and noise from the fan.
most dc fans in good comndition will run at well below 1/2 their plated voltage quite happily with a matching reduction in noise.
I've been doing this for years when noise is an issue for clients.



Whatever you decide.....look for a magnetic levitation fan......these suspend the ermiture and the fan on a magnetic field...they are much quieter than a ball bearing fan and run much longer than bothe ball bearing and bushed fans.

It is reasonable also to run some sort of temperature switch ( simple or complicated) to automatically switch the fan on and off or run it as a two speed fan.

OH...don't think there is a problem with series resistors either......in this situation it is a perfectly reliable and safe method of speed/ voltage controll for computer fans...as long as the resistor is properly selected and mounted.

cheers

Thanks Pop, I assume it is via a relay.
Ian

Ian,

You certainly could use a relay. I just used a suitably rated on off switch to power up the fridge and fan. The fan runs continuously while the fridge supply current is on. Been like that for many moons. Those little computer fans draw bugger all current and seem to outlast most computers.
The fridge will freeze anywhere in the "Top End" no worries.

Cheers
Pop

Hi Ross,
this is the diagram for the common 12V fan conversion. I'd suggest that the extra $2 for a voltage regulator is well spent!


Out of interest, the turbo fans in the E- and F-series only turn on when the compressor is running and the compressor gets hot (because of high ambient temp or heavy use). I've rarely hear a fan on the turbo engel models.

Forgot to acknowledge Brian at GPSOZ who has provided that diagram on his website for the past umpteen years.

"make the fridge able to freeze in 30C ambient because the condensor is able to get cooled an it's heat removed quickly. "

This is the guts of the problem - quickly getting rid of the heat from the condenser.

I made a water-cooled condenser for my van fridge - the Danfoss compressor unit is remote from the fridge so access was ok. It has halved power consumption in hot weather by a combination of reduced compressor speed and reduced duty cycle.

Friend of mine did the same for his built-in 3-way fridge with a significant improvement in hot weather.

Cheers

Frank

Allan,That is what I have done with my old engel,I hooked two computer fans straight to the 12v circuit, one at the bottom sucking the cool air in and another at the top on the grille sucking the hot air out. I also have a switch on the grille to turn them off. Jaycar had all the parts Regards Keith

Keith, are your fans controlled by the thermostat or do they run all the time that they are switched on?

Yep, run whenever they are switched on. Keith.

Oops, should have said power circuit, not 12v. Keith

Are you guys putting the fan inside the fridge case or externally on the face of the side grilles?
I normally have my fridge in my canopy but recently did a long trip with fridge on my tray and I was surprised how much better it ran with good airflow around it, had to turn it up as my beers were freezing

Exactly Hoyks. It is amazing what can be achieved with ignorance.

Hoyks, can you remember where you wired in to the post-thermostat 12V? Was it up near the dial, or down near the input?

It was around 20 years ago now, my memory isn't that good. I can go and pull it apart and have a look.

Hi Hoyks, no need to do that, its just my curiosity - I went through the same thing years ago, but couldn't find a source of 12V DC that came on with the thermostat which is why I did made up the kit that hooks into the 20VAC compressor wires.

Another option I was thinking of doing for my newer fridge is to get a 12v digital temperature controller (around $13 on eBay) and using that to actuate a relay that will supply power to the fridge.


The temp controller has a thermocouple that will fit into the fridge. When the temp gets above the set point the relay will actuate and supply power to the fridge. the dial temp controller on the fridge just gets set to Freeze and left there. Yes, it is made in china and all, but with the right plugs if the thing craps out, you can just bypass it.

With that you could wire it so that when the fridge is powered up so is the fan.

That looks pretty good Hoyks.
At $13 all up you could hardly go wrong.
It has 10Amp current capacity so you wouldn't even need a relay.

Hoyks, Allan,
Are we unnecessarily complicating things? The fridge has a thermostat that does the same job.
If the only purpose of this is to add a thermostatically controlled fan, then why not mount the sensor next to the compressor and use the circuit to switch just the fan?

Well, you could do it the easy way... but where is the fun in that? ;-)

This way though it involves no modification to the actual fridge.

I just bit the bullet and parted with the princely sum of $12.82. I'll let you know how it goes in the new year.

Yes Phil, it is probably not the way I would do it but for $13 it will give Hoyks a digital thermometer and a sense of achievement to boot.