Convert ice box conversion thermostat from analog to digital

[mz4wheeler]

I've had it with my crappy Vitrifrigo ice box conversion kit. The so-called thermostat is just basically a series of 5 "dashes" that I have absolutely NO IDEA what the temperature is supposed to be. I just move it till it "clicks" and hope for the best. This is the crappiest thermostat ever devised. How is this acceptable???

This really needs to be digitized so I actually KNOW what the REAL temperature is, and can actually maintain the temperature of my beer and meat. Has anybody else replaced that stupid worthless dial to an actual, digital thermostat?

I'm looking at this one on Amazon... Very cheap, but I'm wondering if this is just the ticket to my sanity.

https://www.amazon.com/bayite-Fahrenheit-Digital-Temperature-Controller/dp/B011VGAPOC?th=1

Just $16 with FREE SHIPPING... OK, so I am a little concerned about quality and reliability [grin].

 

[Jackdaw]

Leave it alone, and drop the sender to one of these in.

http://www.polarbearcoolers.com/product/thermometer.html

 

[Ralph Johnstone]

Great minds think alike ........... sometimes.

I actually purchased the same one last year with the intention of installing one in our fridge. With our current thermostat, the setting is somewhere between 0.0 and 0.5 (on a scale of 0-10) to avoid freezing everything. It's been like this since day one so I don't think it's a case of the thermostat capilliary having lost any fluid. Just a piece of crap.

I haven't got around to installing it yet but I can say that it worked perfectly when I bench tested it for a few hours using an ohmeter and warming and cooling the sensing bulb.

I figured for the $14.00 I spent on it, I can't go too far wrong even if it does turn out to be a piece of crap.

 

[Rich Stidger]

I bought one of these thermostats also and I plan to install it in the off season. I have replace the OEM thermostat a couple of times and I have fought with it all this summer to try to keep it within a normal range. I think the problem is that it sticks- either off letting the temp rise or on freezing everything. The electronic thermostat I bought looks a looks similar and I bought it on eBay for $12.48 inc shipping. I will test it before installation. I emailed the vendor and he promptly answered all my questions- Can it survive inside a refrigerator -YES. Will it handle a 6-7A load on the relay- YES. How much power does it draw and can it work over a 12-16V range- YES. Be aware that the temp display shows the probe temp and if you clamp the probe to the evaporator like it show be done, the temp will read the evaporator temp and not the internal box temp. I also have a remote reading thermometer like jackdaw posted and it is a great indicator of the current temp as well as the high and low excursions.

 

[jssailem]

Have you checked an old refrig lately. They start at "A and go to F". They are not temp gauges just a potentiometer that allows you to increase the current in increments. Only way to tell the temp of food in your refrig is with a laser temp gauge shooting the food in various places in the box.
Turning on your refrig:

1. Set it.
2. Give it some time.
3. Shoot it.
4. Happy - forget it.
5. Unhappy - adjust it a notch and repeat 2 again.

Digital monitoring of your refer feels like a waste of boat bucks.

 

[mz4wheeler]

Leave it alone

Actually, I think I WILL leave it alone, because it does basically work. What I'm thinking is to just leave the original turned "off" and just install the new one in "parallel" with the electrical contacts to the compressor. This way, if the new digital sensor craps out, I can just remove it from the circuit and use on the original. As a reliability engineer, I like redundancy [grin].

This assumes that the original contacts are normally "open" when the compressor is off... Hmmm... Will have to verify that.

 

[mz4wheeler]

Digital monitoring of your refer feels like a waste of boat bucks.

I just like the idea of setting the temp to 40F, and it just works w/o constantly checking it with a lasar or other external device. I'm more concerned with the current draw, and since this unit draws 3 watts, that ends up being .25 AMPS.

 

[Rich Stidger]

Actually in my case, and apparently not in the OP's case, my thermostat is not working well because it sticks both open and closed and will not maintain a set temperature. I am sick of replacing a $40+ thermostat every few years. That is why I am going change to a digital unit. And as I posted above, the displayed temperature will not be the box temp but will be the temp of the cold plate. I will still set the temperature control based upon the box temperature.

 

[mz4wheeler]

Hey Rich. Odd how yours keeps failing. It is most likely the just the switch contacts operating in a humid, wet environment. When I secure my boat, I always turn off the Vitrifrigo and keep the icebox open to air out. On my unit, the thermostat sensor (the long fat copper unit) is mounted on the wall well below the cold plate.

I found the same unit even cheaper on ebay (thanks for the tip!).

http://www.ebay.com/itm/381455177328?_trksid=p2057872.m2749.l2649

I figure I can protect the sensor wire by using heat shrink. As Ralph said "I can't go too far wrong even if it does turn out to be a piece of crap".

 

[Rich Stidger]

Hey Rich. Odd how yours keeps failing. It is most likely the just the switch contacts operating in a humid, wet environment. When I secure my boat, I always turn off the Vitrifrigo and keep the icebox open to air out.

I agree that it is the contacts. But it should be designed to operate in a humid wet environment. I have replaced the refrigerator thermostat at least twice and the freezer once. It is insane to keep replacing them and hoping for a different outcome. And I also shut off the refrigerator and leave it open when I leave. BTW, even if the current draw is 0.25 A, you are on board and recharging your batteries daily aren't you?