External T/stat for chest freezer

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ILOVEBEER

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Hello,

I bought a manual external thermostat for my chest freezer that I use to ferment my sankes in. I bought it from the CHICompany and personally I think it is a POS!!!! I read the description and thought wow...for under 40.00 that is a deal. The temperature selector is in no way accurate and as an example the pointer is on 80* and the freezer is at 62*. I know I could play with it and figure it out but what a pain in the a$$ it is becoming.


Anyway, I am probably going to send it back and look for a digital one. Can anyone recommend a reasonable priced temp controller please...

Thanks for the help
Joe
 
I am kinda leaning more towards the power interrupter type (where the freezer plugs into the back and the unit remote bulb senses temperture)

Thanks for the help. I should have looked at the digital ones in the first place.
 
UPDATE:

Matt from ChiCompany sent me a new one (without me even requesting) and the new one is alot more precise in the knob operation. The old one must be defective. I would like to retract my statement about it being a POS....Unfortunately I received a defective unit.

It is worth the money.
 
That's great, ChiCompany seems to be a great company.

As a side note, for others out there, "digital" is no more accurate than "analog". It's just a different way of displaying information. Whether that information is right or wrong is another issue entirely. For example, I bet a traceable NIST mercury thermometer is a helluva lot more accurate than my $10 Lowes digital thermometer. Shyte equipment is shyte equipment, whether or not it has an LCD display. In this case, I think, ChiCompany is providing a product at bargain basement prices. The fact that they deal with problems quickly and graciously makes me still think they are an OK company.
 
shortyjacobs,

It does not make sense to me that digital is no more accurate than analog???? That makes no sense.

With a digital cotroller that is microprocessor driven (ranco models for $55.00) they hold the temperature + or - 1* variance. The analog models are more affordable because they are nothing more than an electrical sweep that most of the time is innacurate.

I hooked up my new analog model that Matt from Chicompany so graciously sent out to replace the defective one. I have a very very accurate multimeter that sits along with the thermostat bulb in my sanke thermowell....this is as accurate of a reading that you can get. I have the thermostat set at what appears to be 40*-41* to hold the beer temperarute at 37*.

I read several reviews from customers on the ranco models I speak of and they say the unit variance from setting to actual is ~ 1* difference if that.

Just an observation buddy

Take Care
Joe
 
shortyjacobs,

It does not make sense to me that digital is no more accurate than analog???? That makes no sense.

With a digital cotroller that is microprocessor driven (ranco models for $55.00) they hold the temperature + or - 1* variance. The analog models are more affordable because they are nothing more than an electrical sweep that most of the time is innacurate.

I hooked up my new analog model that Matt from Chicompany so graciously sent out to replace the defective one. I have a very very accurate multimeter that sits along with the thermostat bulb in my sanke thermowell....this is as accurate of a reading that you can get. I have the thermostat set at what appears to be 40*-41* to hold the beer temperarute at 37*.

I read several reviews from customers on the ranco models I speak of and they say the unit variance from setting to actual is ~ 1* difference if that.

Just an observation buddy

Take Care
Joe

While a microprocessor does work in the digital realm, it's still relying on analog information. There is no such thing as a "digital thermocouple". Anything you use is relying on analog information.

I guess I should have been clearer....digital is inherently no more precise, nor no more accurate, than analog. Either could have either drift or a set offset from the "real" temperature.

Mostly, though, what I was pointing out that is that people seem to distrust an analog needle, but fully trust a digital readout, when both rely on the same information.

Edit: It may be inaccurate because it's cheap, but it's not inaccurate because it's analog. Make sense?
 
While a microprocessor does work in the digital realm, it's still relying on analog information. There is no such thing as a "digital thermocouple". Anything you use is relying on analog information.
(snippage)
Mostly, though, what I was pointing out that is that people seem to distrust an analog needle, but fully trust a digital readout, when both rely on the same information.

Shorty, you are WAY off base here, on more than one point. The difference between analog and digital really has nothing to do with a display vs a dial. There are certainly many electronic controls with dials and not displays.

While it's true that electronic controls are using an analog electrical input (variations in voltage, resistance or current), Analog temperature controls (like a Johnson A19, e.g) and Electronic Temperature Controls (like the Johnson A419 and Ranco 111-0000) sense the controlled medium (air, water) in a completely different way. Analog controls have a copper bulb connected to a bellows in the control via a copper capillary tube. The bulb/tube/bellows are filled with a refrigerant (R-22, IIRC). The refrigerant pressure in the bulb expands and contracts in relation to the sensed temperature, making the bellows expand and contract. The bellows is linked to a micro switch, witch switches the load. There are a number of variables, chief of which is ambient temperature, which can affect an anolog controller. Suffice to say that an Analog controller is mechanical, and therefor subject to all the susceptibilities of such devices. For example, prolonged exposure to a dusty environment can make them stick.

The typical ETC uses either a thermistor (JC A419, Ranco ETC, Love TS) or thermocouple (most PIDs, Love TCS), both of which are very stable electrical components, to measure changes in temperature. There are NO mechanical components, unless you want to call the relay mechanical.

I have used ALL kinds of temperature controls for a LONG time, and I can tell you that almost any properly fuctioning electronic control is significantly more accurate than almost any analog control. When a dead band of 4-5 degrees is accepatable, then an analog control is fine. If you want more precise control, use electronic. That is the reason, after all, that such controls were developed.
 
That is what I meant except in a much more educated form. Nice post Fletch.
 
Shorty, you are WAY off base here, on more than one point. The difference between analog and digital really has nothing to do with a display vs a dial. There are certainly many electronic controls with dials and not displays.

While it's true that electronic controls are using an analog electrical input (variations in voltage, resistance or current), Analog temperature controls (like a Johnson A19, e.g) and Electronic Temperature Controls (like the Johnson A419 and Ranco 111-0000) sense the controlled medium (air, water) in a completely different way. Analog controls have a copper bulb connected to a bellows in the control via a copper capillary tube. The bulb/tube/bellows are filled with a refrigerant (R-22, IIRC). The refrigerant pressure in the bulb expands and contracts in relation to the sensed temperature, making the bellows expand and contract. The bellows is linked to a micro switch, witch switches the load. There are a number of variables, chief of which is ambient temperature, which can affect an anolog controller. Suffice to say that an Analog controller is mechanical, and therefor subject to all the susceptibilities of such devices. For example, prolonged exposure to a dusty environment can make them stick.

The typical ETC uses either a thermistor (JC A419, Ranco ETC, Love TS) or thermocouple (most PIDs, Love TCS), both of which are very stable electrical components, to measure changes in temperature. There are NO mechanical components, unless you want to call the relay mechanical.

I have used ALL kinds of temperature controls for a LONG time, and I can tell you that almost any properly fuctioning electronic control is significantly more accurate than almost any analog control. When a dead band of 4-5 degrees is accepatable, then an analog control is fine. If you want more precise control, use electronic. That is the reason, after all, that such controls were developed.


In this case that is all true.

I think Shorty was trying to make a distinction between the sensor and the display. You could have a thermocouple sensor linearized by analog circuitry and an analog display that is very accurate. And you could have a digital device with a lousy sensor and/or poor linearization.

But, as you say, not the case with refrigeration control.

I have one of those bulb based analog controllers, and have finally figured out how to get it to work properly for my mini-fridge for dispensing. The scale is off, but I just compensate. My product varies by about 1.5 degrees F, even though the controller differential is fixed at 4 degrees. It's due to the mass of the product.

Would I rather have a digital controller? Yes.
 
Cool...I learned something. I figured both analog and digital controllers used thermocouples or thermistors....never figured there were some that used a medium-filled bulb, (what an archaic design!!!).

RichBenn, you are right...what I was trying to get at was that digital doesn't necessarily mean better...(for example, an analog multimeter vs. digital multimeter. People will believe the digital multimeter more, and will quote things like, "I had 12.128 volts", when really the digital one is just as susceptible to bad calibration as the analog)...

Very interesting how those bulb thermometers work....like plugging a mercury thermometer into a pressure transducer! How weird. Thanks for educating me folks.
 
In this case that is all true.
(snippage)I have one of those bulb based analog controllers, and have finally figured out how to get it to work properly for my mini-fridge for dispensing. The scale is off, but I just compensate. My product varies by about 1.5 degrees F, even though the controller differential is fixed at 4 degrees. It's due to the mass of the product.

Would I rather have a digital controller? Yes.

I still use (analog) A19s on my kegerators - as you say, they do the job they're designed to. Hell, the control inside most refrigerators is the same, and refrigerant pressure controls are the standard for >90% of commercial refrigeration, etc. I only use electronic controls for actual brewing, for both accuracy AND rapid response.
 
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