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  1. verne

    verne Member

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    I just received my new dual temp gauge .The web site I bought from stated 10 foot leads , in actuality they are 10 INCH . Can I use standard thermostat wire to extend the lines from the the thermocouples?

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  2. sdrobertson

    sdrobertson Minister of Fire

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    Same thing when I order a couple of weeks ago. I email the company but got no response. I hooked them up to approximately 6' of small gauge wire(I don't remember what it was now) and they seem to work just fine. I was quite irritated when I got mine as like you said 10" is allot different from 10'.
  3. verne

    verne Member

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    I have not recieved a response either .when I looked at AZEL's site they say 10 " , so for the better price ?? I will just suck it up and try to make it work.
  4. sdrobertson

    sdrobertson Minister of Fire

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    A Siemens controller uses the same signal I think and the manual states 900 feet so I don't think there is a problem. Its just irritating.
  5. Nofossil

    Nofossil Moderator Emeritus

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    You might have a problem. Thermocouples work due to an effect that you get whenever you connect two dissimilar metals. Thermostat wire would introduce additional junctions with another dissimilar metal. If it were me I'd try it, but don't be too surprised if it doesn't work. You can buy thermocouple lead wires - just make sure that you use the right ones on each leg, because they're different.
  6. sdrobertson

    sdrobertson Minister of Fire

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    By not working would you expect an error code or just a small false reading. I have 3 different temp gauges (azel - boiler gauge - and the eko) in the same line and I get different temps at all locations. Not much (+-5 degrees), but different. I just assumed that it was a calibration issue but I want to move my azel probe to a different location. The wires on the thermocouples are not identified - they are both the same so how do I determine which is which? Just when I figured I was figuring this out...
  7. deerefanatic

    deerefanatic Minister of Fire

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    They may be thermisistors instead of thermocouples.

    I know for a fact that Nofossil is right on this. I used thermocouple wire to extend one thermocouple I had that was short. being the nice guy that I am I soldered the joints and taped em up with electrical tape. Wrong think to do!! The controller worked fine, but it would only show the temperature of the soldered splice in the wire!! Not the temp of the probe itself. I cut that splice out and just twisted the wires together and taped them back up and viola! worked just fine.
  8. Nofossil

    Nofossil Moderator Emeritus

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    Thermocouples should be a lot more accurate than +/- 5 degrees. They usually have color coded wires - red any yellow, if I remember right. Can you move them around and see if the difference moves with the thermocouple? What happens if you swap leads?

    Perhaps a final question: Are you sure that these are thermocouples? There are other types of temperature sensors out there with different characteristics. If it's a thermistor, you could extend the leads with no problem.
  9. deerefanatic

    deerefanatic Minister of Fire

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    Red & Yellow are the colors for K type thermocouples. Other types use different colors.
  10. sdrobertson

    sdrobertson Minister of Fire

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    The sensors are thermistor sensors so that must explain the wires being the same type and colors. Looks like I got lucky and now I have learned something else.
  11. Nofossil

    Nofossil Moderator Emeritus

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    At the risk of being pedantic (gotta love 'pedantic' - it's its own definition, kinda like 'eschew obfuscation').... wait a minute - I just created a sentence with 'its' twice in a row, that's actually grammatically correct!

    Where was I....

    Thermistors have a couple of advantages. They can be located very far away. Long wire lengths have almost no effect. They provide a varying resistance that's typically thousands of times higher than the resistance of the wires. They're very inexpensive (though not necessarily so after they've been packaged and resold). They don't require complex electronics.

    Couple of disadvantages though. They're not as inherently accurate as other sensor types. They're very nonlinear, which reduces their usable resolution especially if you want to use them over wide temperature ranges. They're extremely moisture sensitive, so they have to be carefully packaged and even then are more likely to fail than most other sensor types. They are not usable at high temperatures.

    Bottom line: I use thermistors at present for everything except flue and combustion temperature measurement. I'm switching to a somewhat more sophisticated semiconductor sensor fairly soon, mostly to get away from thermistor calibration issues.
  12. sdrobertson

    sdrobertson Minister of Fire

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    Generic question - do most controllers(meaning the "box" that displays the digital temp) use the same signal between thermistors and thermocouples? Can they be interchanged or do they need different controllers? When I go shopping for digital temp gauges what am I supposed to look for so I know what sensor a certain unit uses?
  13. Nofossil

    Nofossil Moderator Emeritus

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    They are *quite* different electrically. A controller will work with one or the other, but definitely not both.

    To make matters worse, there are many types of thermocouples that are not interchangeable, and probably hundreds of different and incompatible thermistors.
  14. sdrobertson

    sdrobertson Minister of Fire

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    Thanks - now its a little clearer. I understanding now that I need to look closer to what I'm purchasing and what will be compatible with what. Someone would be able to retire confortably if they came up with a "plumbing for wood boiler with storage in a box" kit that would control inlet and output temp with included control and temp reading in a easy to use kit. Purchase boiler, storage(open or closed) and "PFWBWSIAB" kit - three hours on the weekend and your set for 25 years of free heat.
  15. Nofossil

    Nofossil Moderator Emeritus

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    I've had more than a couple of inquires about packaging the NFCS (NoFossil Control System). With my luck, someone would install it, burn down their house, and sue me.
  16. pybyr

    pybyr Minister of Fire

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    nofo-

    I am among those who think that the world (or at least the Boiler Room) is ready to beat a path to your door, with money in hand, if you can develop and deploy a scalable, configurable "brain" that could be installed and then set up by non-software-savvy types, to run various reasonably common variants of : (wood boiler) (fossil back-up) (hot water storage) (zones)

    somethin' tells me you certainly have the technical and practical savvy

    the liability part can be dealt with two ways, both readily handled by competent professionals in the legal and risk management fields:

    1) get a signed waiver from every customer on the order form, before they pay, and before you deliver, that this is a total DIY product that you have no control over the end use of, and they expressly agree that they are on their own in end use, and indeed, agree to defend and indemnify you from any claims made against you.

    Other sorta similar products are out there and have not been crippled by liability problems. Google up the "megasquirt" and "microsquirt" brains for DIY fuel injection retrofits to older hot rod vehicles. the potential liabilities for burning wood are _nothing_ compared to the liabilities associated with hot pressurized gasoline in modified performance vehicles used on the open road!!!!! Or the Birchwood-Casey .22 swing target I bought this morning to use for target practice with my son, which has a big disclaimer on the package that the Mfgr has no control over the end-user's use, and so disclaims all liability for outcomes.

    2) get an extra "umbrella" policy for "Nofo, Inc," which probably, actually, shouldn't be all that expensive compared to the risks you have (and I assume you are insuring) in your preexisting business ventures in the "IT" field that you work in

    __Truly__, PM me about talking about the above variables, where, unlike almost everything else around here, my background happens to have more hands-on than your background.
  17. pybyr

    pybyr Minister of Fire

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    The world needs more "pedants" like NoFo,

    and the more pedanticness you share with all of us, the better the world is!

    ProBonoPedanticness- pass it on !
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