Refrigerator Problem

Remember....the spec on the fridge is the running watts+ amps...
Things with a motor need a surge to start...usually 2x the running power to start the motor(that is the calculation for a generator, but 40-50% + is more realistic).
The fact you have a 10 amp breaker x 12 volts = you cannot get 400 watts on a plug in inverter....it is limited to 220-250 maybe more (most trucks have a 15 amp fuse)....remember volts times amps equals watts...truck running is 13.8 volts times 15....
If you need more than maybe 70% of that, then a motor will not relilablely start, cause you cannot give the inverter enough power...

 

Read my first post. 150W start and 70W running

 

I have a short frightliner...same interior space...
I have one of those Coleman fridge bungiecoreded to seat next to me...pretty cool as long as the truck is running with the ac on for the summer...was super cold for the winter. It will cool to about 30-40 below the outside air temp...so 80 in the truck gives you about 40 inside, fine for most foods for a few days. Was like $85 at walmart.

 

Most inverters produce a modified sine wave...it is stepped, rather than smooth....this means some items, like ones with motors and microwave ovens sometes don't work as well...try a different inverter maybe...a pure sine wave inverter is usually cost prohibitive...but quality of modified sine wave varry lots....even buy how they are rated...running watts/surge watts.

 

I have the same fridge as you. The numbers I gave you are off the inverters digital read out. Yes, you are correct about the sinewave. You get what you pay for.

 

So, the issue is in the starting of the compressor motor requiring more power than the 12V socket can give.

Just a little reminder: The truck uses a 20Amp fuse for the circuit I'm trying to plug this refrigerator into.

So, at 20 Amps x 12 Volts = 240 Watts is the max that the 12V socket can give me.

So, still, the refrigerator should be able to start AND run. (Assuming the issue isn't with modified sine wave.) Yet, it's not. The fuse in the dashboard blows.

What would happen if I put, say, a 50Amp fuse into the slot? 50 * 12 = 600 Watts. Instinct says don't because that's not what it was designed to do--all the 12V sockets have a 20Amp fuse by default. I feel like it might melt the wiring, potentially catching on fire. But then, on the other hand, it doesn't need that extra boost of power except on start up. It doesn't need that amount of power constantly. Only for 2-3 seconds at most while the compressor starts.

 

Son, my GrandDaddy taught me way back when ... "Insanity is doing something over and over again, hoping for a different outcome".

You have several folks posting here informing you that you need a larger inverter, directly wired to the batteries of your truck, in order for you to power a home-styled dorm refrigerator.

Just what exactly do you not understand with our responses?

You are exactly righ re: putting a 50 amp fuse in ... you face the huge potential of burning up the wiring and starting a fire in the truck.

So, again, here are your choices ...

1) Install a larger inverter, direct wired to the batteries. (Which your company prohibits.)

2) Return the current refrigerator to place of purchase and get a thermo-electric cooler. (Cooling temp approx 40 degrees below ambient temp.)

3) Buy a Koolatron 40B and you will have the best of both world ... as efficient cooling solution as possible using Heat Pipe technology (step bteween a thermo-electric cooler and a regular refrigerator) and it plugs directly into the 12 volt outlet.

4) Buy a TruckFridge TF-32 and you have a full fledged portable refrigerator with thermostat ... and it plugs into the 12 volt outlet

 

I understand what you guys have been saying (98% of it, anyway) but I'm not the kind of guy to give up on something at the first hurdle. Granted, many before me have gone down this same path, had the same issues, and come to the same conclusions. But no new solutions can be thought of if you accept conventional wisdom. Columbus was told he couldn't do what he wanted but did it anyway. And look what has happened because of it?

I was hoping, maybe just maybe, a new solution to an old problem might have been able to be found.

Alas, I'll take a look at the Kooltron 40B. I've had the Coleman cooler before and didn't like it. They fail quite often. The TruckFridge was way too expensive.

 

The fuse protects the wire. You put a bigger fuse on it, you might be melting things.
Them inverters are overrated I think. The little ones are only good for a laptop or cell phone charging.

The 800 watt comes with supply cables and alligator clips on them. But that would only be a temporary hook up. If you figure out how to keep it weather-tite outside, you could run an extension cord inside. Any outside tool boxes?

 

Dosnt really need to wire it directly to a battery, an idear I have is to take a deep cycle battery from my fishing boat, 65.00 at walmart, and connect the bigger inverter to it, during the day while you are driving you can run a smaller inverter to power a battery charger to charge the battery. Bedies the start up surges, the draw off the deep cycle isnt that bad, a 5-10 amp charger will keep it fresh nicely and when you need the big draws you have the 1100ah at your disposal. Just sayin, flame away. lol