Inside a cheap eBay fridge freezer thermostat
HTML-код
- Опубликовано: 1 окт 2024
- A look at how capillary thermostats work and how to use them.
Capillary thermostats are a simple electromechanical thermal switch that uses a very thin metal tube to sense temperature at another location, by using the thermal expansion/contraction of liquid or gas to activate an adjustable switch.
The search keywords for finding a wide range of units on eBay are:-
"refrigerator thermostat"
Note that there are quite a few similar looking versions and a massive price range for the same thing.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.co...
This also keeps the channel independent of RUclips's advertising algorithms allowing it to be a bit more dangerous and naughty.
"We don't know what it is, but here it is!"
--99% of all online redistributers
Well, not every Chinese seller is even this sincere!
I've found that out. Makes explaining and resolving problems very difficult. eBay tends to favor buyers but I sometimes think sellers get the sort end of the stick.
@@tomschmidt381 hahah, currently one seller on Ali ignores my messages after sending me the wrong item labelled as the one I ordered. Opening a dispute can help, maybe, but their immediate response was refusal explained like «delivered, ask your local post office or relatives about it». I mean… WTF? How could my local post office be responsible for a warehouse error?!
6:14 because it's cold it will be retracted in, said every man.
Clive doesn't, he starts working below 10°C
3:35 and then Clive pulls Simon's knob off.
"This is where it bursts and squirts unknown chemicals everywhere"! Carry On Clive!
I once cut one of those tube-wires, the fluid was pretty much reactive with humidity and almost set my lab on fire!
@@olipito Alcohol based.
Sounds like the title of a 70's movie 'carry on Clive'
@@CanadairCL44 thanks for the answer. Do you have more details on the chemistry of the fluid?
same, but it was an oven one.
BigCliveDotCom: Causing shipping managers everywhere to scream when they find out how much it costs to ship to the Isle of Man.
It costs more to ship goods to the UK mainland from Europe now we have reintroduced customs formalities, though .....
I've learned a new excuse: "I didn't drop it, those are calibration dents"
Nop, thoses are "speed holes" xD
Dent tuning waveguide is a thing. Kinda alarming the first time you see it done but it’s very effective.
I'll try this next time retuning a rental car.
"so you can't RAM IT RIGHT PAST THE END STOP." Gig-gi-ty.
Shades of Quagmire LOL !
"Ouch!" said her cervix.
"Panty rings for extra security while horse-riding."
There's so much to unpack in that little sentence.
😂🤣😂
i laughed out loud at this :D taking the piss out of the panty liner adverts but delivers it so deadpan like.
love it :D
Today's "liberated" female rides "free bleeding" as well as runners. Eww...
wings*
Slightly unrelated: my father found previous work done on a commercial fridge, where the owners got a local handyman to fix it.. The handyman cut and joined a capillary pipe with a strip connector because he thought it was a wire and couldn't figure out why it still wasn't working...
Brilliant!, You get what you pay for.
That’s gold 👍
I've witnessed sooo many people joining coaxial antenna cables that way, wondering why the signal's gotten even worse after their "repair"... But the capillary tube thing is new to me.
How can people be that dumb?
His name is "Nowis", Clive!! You wrote it right on the side of the device!! ;-)
I was also troubled by this, for the first minute or two :-)
16:11 "This has little wings that fold round, little pantie-wings that fold round, for extra security when you're horse-riding." And those who watched ITV in the 90s may understand why this makes me think immediately of "UUUAAAAARRGH, BAAHDYFORM!"
LOL :D
I wonder if those little wings stick to hemp panties?
I haven’t heard it in years and you made it play back perfectly in my head. God punish you.
There's a Mr.Bean episode where he can't sleep. He puts the TV on and there's a chess tournament, he's about to nod off and the Bodyform ad comes on and scares the crap out of him :D
Those big bulbous knobs would look good on my steam punk electric guitar. 🎸 Especially going up to 110, it'll make it louder. 😉
If you put on the -30 to 30 knob, does the guitar start sucking sounds from the air, making it quieter as you play?
@@RedwoodRhiadra That's got to be worth a try. 😂 I need a new guitar amp, my old one definitely sucks!
Ah! So that's what those things in my oven are!
I've had to remove our oven from the fitted kitchen cabinet four times¹ in the past year to replace the mode selector switch and then one of the heating elements, and I saw these two metal tubes leading from the thermostat dials to each of the two ovens, so they were clearly for temperature sensing but, only being familiar with thermistors, thermocouples, PT100s, and similar *electronic* temperature sensors, I was expecting something like that (i.e. at least 2 wires), so only seeing a single metal tube totally confused me!
¹ Removing it twice per replaced item: once to get the details of the broken part that needed ordering, then later to actually replace it. The heating element was less than £10 from Amazon, so I was a bit doubtful about it, but it's been working fine for a few months already. Although with the amount of time it takes to replace the heating element on my oven, it'd *definitely* be better to buy the ~£30 version if this £10 part fails in short order!
Since I was a child I have imagined that the thermostatic control in an oven works by means of a bimetallic strip. I am fascinated to learn that I was completely wrong and ovens use an entirely different principle.
Likewise I would have been dumbfounded! Good on you for knowing the value of your labor!
@@zh84 You don't need the amplifying effect of two different metals with the temperature difference between an oven and ambient.
Now, the hob controls _do_ use a bi-metallic strip; only it is not actually sensing the temperature of the cooking ring, but a separate little heating element which just heats the bi-metallic strip. This and the ring are wired to come on together, so the rate at which energy is delivered to the food (i.e., the mean power output) is proportional to the mean power output of the thermostat's own little private heater, which you adjust with the knob. It's an example of a feed-forward control system.
@@bluerizlagirl Interesting! I had no idea that's how it worked. Thank you. I took a lot of things to pieces in my childhood, but never a stove.
almost a half hour of big c pulling his knob, thats hot!!!
The capillary full length sensing fridge thermostat is designed to be installed entirely inside the fridge, turning the knob only with the door open.
Thats true, but MOSTLY if you have a freezer inside, the eond of the tube is IN CONTACT wirh the wall of the freezer!
@@Mtematiks Thermostat regulates compressor runtime to keep main fridge compartment at the set point , Supplemental freezing box gets whatever it gets by thermal design, not by touching any sensor .
The sleeving on the capillary tube is probably to avoid getting kinks. That's a very common failure mode for these things. Most of the waterbed heaters that I've owned over the last too many years have used those stupid bulbs and capillaries. I was really happy to get one that had a thermistor to put underneath the mattress and nice flexible wires instead of that damn bulb.
As far as prying up tabs goes, you should get yourself one of the chiplifters from Wiha. They are essentially a miniature crowbar with an end that's maybe 1/8 inch across and curved so that you get leverage to bend things up.
the isolation provided by the sleeving is a fine tune for the system
Mostly they are insulated to avoid shorting on bare electrical and objects running into it rubbing a hole. Forgot to unplug a unit on a repair and got too close to the terminals inserting the capillary tube and pop! Off to see the wizard for another one.
Yes, it's purely for electrical insulation, the center screw is for calibration. It's just a run o the mill thermostat. High temperature regulators could "explode" at the moment you cut it like he just did.
The little "diaphragm" on the second unit is typically called a bellows.
3:33 i will be pulling my knob off later 🤔😬
Look up the MSDS (material data safety sheet) for a Honeywell aqua stat. They list their capillary liquid as a mix of Mineral oil, lithium hydrostearate, Zinc Alkyldithiophosphate, and a few other aluminum components, and stearates. I looked it up on a job one day when I had gotten it all over me. Wanted to know if it was carcinogenic. They say it isnt.
Similar thing happened to me with a barrel of MEK. Isn't it great that everything can be found online? Whereas before shops had to keep volumes of paper.
They say it's not carcinogenic, but I bet when they sell it in California it has that famous cancer sticker on it 😂
@@tin2001 Known in the state of Cancer to cause California ;]
Pretty "cool"! I'd never really thought about these before, but the engineering is really pretty elegant.
I also really love the tiny metal accordion.
Just a few pounds/dollars on eBay if you want one for the bits.
heh hey there bruxxus
@@darkmann12 Howdy!
The tiny metal accordion is a bellows ( en.wikipedia.org/wiki/Metal_bellows ).
The processes for making them are pretty cool.
For long lived thermostats they can be made by hydroforming ( ruclips.net/video/TUam4SHbNJw/видео.html ) or electrodeposition ( ruclips.net/video/OTR4SJRVcCo/видео.html ).
The bellows in Clive's video were most likely hydroformed as they are much cheaper.
Hats off to Clive for educating and entertaining us!
Love your work Clive. The last thermostat you pull apart you refer to its calibration screw. I think that screw is actually the "differential" temp setting, it works like a sensitivity setting, by adjusting the tension on the spring mechanism. The user-adjustable knob sets the temp at which the thermostat turns off . The sensitivity setting adjusts the temp at which the thermostat turns on, which for fridges and freezers is fixed at about 3 - 5 degrees above the temperature set by the user.
'it could be some oil or...." me waiting for him to taste it....
"A chap called Nowis"
I'm glad it wasn't only me who wondered who "Nowis" was in the opening seconds of the video... :D
what a lively thread, i just had fridge/freezer re-gassed, after that it was running continuously, fridge down to 0.6C° and ice build up on suction pipe at compressor; figure thermostat must be faulty, replaced it with identical new WDF28C-L-EX, no change, it either still runs too cold, or after turning one of these small screws, the compressor cuts out, but doesn't come back on; also, my thermostat has got 3 tiny screws, one on the front (knob side) and sunk in, another on the side, which made the compressor cut out when turning and a third even smaller and sunk in brass screw on the backside; i can't find any information what the actual functions of all 3 screws are, any ideas here ? thank you
I always wondered how these thermostats worked. Thanks for the video it was very informative.
movement of the drum has to be slight as it is magnified by the armature due to its closeness to the pivot
The Opening Things Up Channel.
Hi Clive. I'm heavy into antique and vintage refrigeration equipment. The ones with the saturated vapor capillary tube are very common with the old fridges. They depend on the sensing tip of the tube to be cooler than the body and diaphragm of the switch. The vapor pressure of the working fluid is what really gives these their accuracy.
I've made several videos of rebuilding these when the sensing line gets broken.
Depending on the temperature range the control was designed to work at, they used different working fluids. Some of them used sulphur dioxide; methyl chloride, Freon-12, isobutane, or propane.
When rebuilding the fridge thermostats, if you can determine the temperature it is supposed to switch it, you can apply gas pressure and determine what pressure triggers the switch. With that information, you can consult pressure-temperature charts and find a suitable refrigerant gas to use for a working fluid. One of the original manufacturers of the vapor type thermostats is Ranco company. They have been in it for decades and have published quite a lot of repair info in the past decades. Ranco are still around and still very high quality. I think the second one you had in this video was a Ranco knock-off.
Many of the ones I've rebuilt recently ended up with butane being the correct gas.
Back in the old days, they referred to the ones with the expanding fluid (like the first one you worked on) as "hydraulic" thermostats. The ones with saturated vapor were called "gas" or "vapor" thermostats.
I've been wanting to study and learn to repair the "hydraulic" type of controls. There are few who repair them when the capillary tube gets broken. The secret (as you said) is in the thermal expansion coefficient of the working fluid.
Here's an isobutane thermostat getting repaired: ruclips.net/video/WHv9Ut7guwE/видео.html
This one was originally methyl chloride, but I used 1,1,difluoroethane for it. It's almost like your second one you showed. In spite of being very similar, it's from back in the War of the Currents era in the States. Back when AC and DC were both competing technologies. Love the old stuff! Repair video: ruclips.net/video/H7VQys1gPjk/видео.html
Thanks for the teardown video! I enjoyed it a lot. I hope you enjoy seeing my repair videos on these.
You are spot on. Glad I read through and didn't repeat your comment.
I do HVAC cold and hot side equipment repair you got yourself a sub good sir I love old equipment your living my dream homie I'll be there one day
@@jabroski69 Thank you, much appreciated!
I think that liquid is called a refrigerant it could be HFC example R134a. Thanks Sir
These "hydraulic" thermostats had to be calbrated for use in high altitudes. Also if you can find an old Cutler-Hammer thermostat, they not only have a method of calibration but separate screws for adjusting the cut-in and cut-out.
Ugh... I've a similar kind of thermostat in my HVAC heat pump, line voltage mechanical thermostat... its temperature range fluctuates so it's terrible to manage, getting it replaced with a digital thermostat this spring :)
Mineral oil, I'd wager.
With fungicide.
This brings back memories of when I was a quality manager, setting up inspection section procedures at a domestic gas boiler manufacturer, in the mid 1980's. Best job I've had in years!
The 1st time I dealt with one of these I thought that tubing was an encapsulation for the sensor(that I thought was a thermocouple, thermal transistor, etc). I opened the vial and, to my huge surprise, it came out an oily fluid. I washed my hand several times, because I didn't know if that could be poisonous. It turns out that the oven was 100% electro-mechanical. I remember taking some time to understand what was going on, but eventually came out with the conclusion(that was correct).
I love these mechanisms... they are like puzzles.
_"was 100% electro-mechanical"_ Quickly converted to 100% dysfunctional 😁
You are practical as well as theoretical, very good sir
This was very helpful i was trying to figure this out after watching HVACR videos. A quick google was failing me but explained in the first 30 seconds. Sometimes the capillary connects to the system or to a bulb but either way the point of the capillary is to transfer the pressure with a small impact of the volume of the capillary.
I'm sitting here yelling "press the middle"! :-)
So you after you got your fingers messy, you peeled back the protective wings, crushed the diaphragm and the lost your mind for minute as stuff sprung out? That's more fun than I had last night!
The two with a vial are for sensing the room/box temperature, the last one is made to sense on the evaporator, and it matters a lot to get the right type for your application.
A two Fridge Freezer Home, Owning a 12 year old Fridge Freezer, in 2019 it began the pool of water on the floor by the freezer door. Seeing the build up of ice behind the plastic inner back case, So switched off and did the Defrost instructions. Two months later the pool of water again. So after watching Videos of how to fix Fridge Freezers, After defrost, Off comes the inner back cover, Ohm meter test the defrost censer ( all Ok ) then plastic pipe cleaner prodded the water drip pipe to the drip collection tray on top of the Pump ( No Blockage found ) Reassemble, and switch on, Two months later Pool of water on the floor. So Call a Local Fridge repair, he did every thing I had done £55 Bill. Two months later Pool of water on Floor. Call Local repair under 3 mths Grantee, He tests and did same no fault found other than the ice build up, said it must be a controller PCB with an intermittent fault. He did an online search for a replacement PCB, But the Fridge Freezer was to old and the PCB no longer available. So time for a new Fridge Freezer we thought, Wile making our mind up about which one to buy 2/3 weeks pass with the Fridge Freezer off, After a shopping trip No room in the other fridge Freezer decided to switch on old Fridge Freezer, That was in 2019, No Pool of water to date.
A refrigerator too old so the PCB is unavailable? I've never had one with a circuit board, it's just been chassis wiring. But here the new fridge is from 1997, it just has a basic thermostat like shown here, a motorized defrost timer, and no fancy electronics. I'd guess yours is more advanced, maybe a digital temperature control or maybe even a two-speed compressor.
Aww you didn't set fire to the oil! It burns really well. The last 2 I cut open the oil smelled a lot like standard 28 second heating oil, and it burned quite nicely once warmed. (well it burned with a lot of smoke anyway...)
???No Fire??? Downvote!!..jk
The couple I've found data on were filled with oil and fungicide/corrosion inhibitor. Google tributyleneglycol biborate which is an endocrine disruptor and stay away from the smoke or skin contamination. I really wouldn't burn or even mess with it.
@@Peter_S_ "endocrine disruptor - skin contamination"
You mean Clive's gonna grow boobs now?
@@Aengus42 No, they would have to be moobs I think. They used the same chemical in hydraulic fluid for the giant missile elevators I used to occasionally repair so I looked into how bad it was to be coated init when changing seals or replacing components. It's an EPA registered pesticide and biocide so I wouldn't recommend it as a drink mixer.
@@Peter_S_ I wonder what qualities it had over normal, bog standard hydraulic fluid for it to be worth the risk! Especially seeing as it must've been in fairly large quantities.
I worked a hydraulic weed barge on UK canals and that stuff you could bathe in!
(I'm kidding, but it wasn't hazardous.)
On the freezer thermostats I’ve seen that are mounted inside, they have all been filled with some type of refrigerant. Interesting to see one that is just oil. I believe you can tell the difference by not only the diaphragm but also the expansion bulb. The oil ones appear to have a much larger surface area for the expansion bulb whereas the ones with a refrigerant have extremely small, almost non-existent expansion bulbs. Probably due to the thermal sensitivity of refrigerants.
Remember the old Teddington QR stats, they used sulphur dioxide as the sensing gas!
Just to be extra manly? Seems reasonable. I’ll take three.
@@WineScrounger probably 40 years ago now i think about it, used to help dad out at work on school holidays!
@@heavydiesel cool stuff. I can’t see sulphur dioxide passing the sniff test these days. Although I do wonder if some thermostats would rely on a phase change for temperature sensing. Maybe that’s the reason?
A delightful exploration!
In our scrap area at work I'm always finding rolls of copper capillary tubing that have been cut. Always wanting to find a use other than a magnetic loop antenna. LOL
You could wrap it round a heating element to make a simple smoke machine. Not sure how long it would last though.
@@bigclivedotcom that just sounds like me getting in trouble at work... I'll get right on it! LOL
Over the years I've changed lots of these - ovens, water boilers, water and oil filled heaters. I've never seen any fault different from spring relaxation of the switch mechanism caused by faulty contacts overheating it. Expanding sensor-actuator part might be a dark sciense for a lazy person, but the spring mechanism of the switch is a real engineering voodoo. Changing heater thermostats in my very old apartment, however, became a very difficult task - they were made in England, but apparently no more so getting new one is a quest of walking through all spare parts shops without websites in criptic parts of the town.
In the stream tonight, could you maybe explain how a mercury rectifier actually makes current dc?
(and he never did)
The thermostat in my electric heater died. Took the unit apart and pulled the faulty rotary temperature control. The old part no. KST220 and says it's rated 15A 250V.
I type the part number into the interwebs and I'm finding a physically identical part however they are all rated 10A 250V and I'm not sure what to do as the heater draws well above 10A.
Suspect the they used to over rate the amperage, thus continuously failing, and they lowered the rating all all the new parts. The contacts in the old switch were burnt up.
Not being able to find a suitable part I'm about to by pass the thermostat altogether and manually switch the heater on & off. Any recommendation would be greatly appreciated.
Just use the 10 amp one. It will last for some time.
If you know what your doing, you could have the thermal switch send power to a relay, that sends power to the heater elements.
@@COBARHORSE1 Using a 10A switch on a 15A circuit is not something I'm going to do. The 15A switch didn't even last one full season!
Relay coils are low voltage. The heater is high voltage. Where would I get the low voltage? That solution requires additional components, cost more, and adds additional points of failure. Not feasible.
Thank-you for your reply and throwing some additional ideas in my head. :-)
@@STONEDay relays come in a wide variety of coil voltages. I'm sure you can find one that will meet your requirements.
www.amazon.com/dp/B0078S2HBW/ref=cm_sw_r_cp_apa_fabc_Bwn-Fb63GSETJ
@@STONEDay relay coils come in many different voltages.
I'm quite sure you can get a relay with a 240 volt AC coil.
@@m.k.8158 I put some more brain cells on this relay concept...I have SSR & coil relays. Every time I have used/implemented a relay it was between two different circuits. The heater has one high voltage circuit (was just staring at the wiring diagram on the unit). I don't see how I connect one high voltage circuit to both ends of a relay without additional components. Getting too complicated vs bypassing the switch.
Thanks for your reply. :-)
@15:28 the knob does not rise and fall to the case, the red rotating wedge increases or decreases the force on the diaphragm lever changing its position and/or resistance to movement creating a manually variable switch on/off state. @20:31, you got it!
BigClive well UK customs be like why is he ordering these when it costs money to ship to the isle of Man I assume the liquid in the thermostat isn't Mercury in case it is dispose of carefully
It's just an oil.
@@bigclivedotcom I love watching your videos often I find them fascinating
Dead simple (and remarkably reliable) mechanism! Able to (reliably) switch decent current too, so an example of excellent (although nowadays decidedly "legacy") engineering. As you say, almost "everything" these days will be electronically controlled (pre-programmed PID controllers) which (though offering far closer control ranges) do seem to be far less reliable, despite "no moving parts inside".
I think the "gas" would be something like Freon, and it's transition from liquid to gas depends on the temperature and pressure (the state transition giving much more decisive action). Plus the two adjustments are to set the amount of Hysteresis as well as the Temperature.
_…little wings for extra security when you're horseriding…_
Bwhahahahahahah!
the capillary is usually filled with refrigerant r22 or butane
This was an oil that lit when heated.
@@bigclivedotcom the refigerant is under pressure with a minute bit of oil in
You seem to have got off lightly. I used to be a refrigeration engineer and to the best of my knowledge the gas in the phile is ammonia. I've certainly broken some over the years and can confirm you do not want to be breaking them next to your face! :-) Maybe they no longer use ammonia, I dont know but they certainly did in the past.
Need a cup of ice water to dip it in right after heating with the heat gun.
But the ice water would be warmer than Clive's ambient room temperature.
I replaced one of those cap tube with gas in type thermostats once, it was new but the owner of the fridge said: That wire was too long when we installed the new thermostat so we cut it shorter..................................
Holy Mechano Batman !! Why so complicated ? This the New World, Piezoelectric, FETs, Lasers, Pink Mosquito Zappers. Or am I the victim of another 'Mandela Effect'... oh, the humanity ;)
Maybe its mineral oil inside there? After all, we know how much that would expand and contract. Maybe with an additive for low temps. Or just a lightweight oil.
You really got me shouting at my screen this time 😁
The gassy one might have been liquid within it's operating temperature range...
And the more narrow the diaphragm, the bigger the travel for a given expansion of the medium used.
That type tends to use a small amount of a low boiling point refrigerant such as butane or freon in the bulb,which is gaseous under the relatively low pressure within the capillary. Since the temperature coefficient of expansion is much higher for a gas, but the force that can be applied it much lower (since gas is compressible) the bellows is constructed to deal with much more movement than the liquid based thermostat.
@@ferrumignis I was thinking it would be most effective during it's transition fase...
The "sleeve" is almost certainly more for physical protection than insulation.
The last thermostat you took apart is indeed for a freezer. My Arctic King 5 cubit foot chest freezer has the exact same thermostat.
It's so cheaply made that over time, the small vibrations of the compressor cause the set screw to turn, which causes the freezer to to stop getting as cold after a few years. Most people just throw the whole unit away, but it can be fixed by simply adjusting the set screw on the side. Mine is especially bad and has had to be adjusted twice in 3 years.
Meanwhile, the freezer on my fridge from the 1970s has been holding 0°F for 40 years and hasn't missed a beat. It's sad how cheaply things are made now.
That part number is for a GE fridge thermostat
That could explain why the third thermostat looks remarkably like the one in my GE fridge. But AFAIK mine doesn't have a third contact.
@@eDoc2020 the 3rd contact is just a line jumper that sends 120v to board for the "fast cool" feature. All it does is bypass the thermostat and power the unit to start cooling when you hit the button
@@TheWhiteAfghan AH, I've never had a fridge with that feature. For that matter I haven't had a fridge with a circuit board, only conventional thermostats and defrost times directly connected on a harness.
@@eDoc2020 those were the good ol' days.. im an appliance tech 😁
we use silicon oil or glycerine as transmission liquid in diaphragm seals :)
In honor of Kevin Greeson , the bloke who killed himself by tasering himself in the ballocks during the raid on the Whitehouse, could you try cooking a jacket potato with the electrozaponator? TIA.x
Could you explain the extension spring at 20:08? I turned mine whilst trying to calibrate and I don’t know where it should be😮
you're good at making stuff up as you go :0
RUclips captions at 1:02: "... since changed the listing so it does not ship to Alabama ...". Where is it you live again? It must be your southern drawl they have trouble with, Clive. :-)
Typical, I spent 2 hours today diagnosing why my fridge/freezer was not working. I figured out it was the thermostat then figured out the diaphragm was not working. I could have saved myself a lot of time if I had watched this vid first!
14:30 I’m still working on my carefulness lol. Always have little scrapes, cuts on my fingers from tinkering.
Also with that part that he totally discombobulated it when he took it apart and totally goofed it whatever you want to say well as you doing this channel chances are it's not going back together again anyways!
Yo kind of doing it for science you now or the curious or the people that would do it for themselves or whatever.
As most of the stuff is bad or defective or whatever in the first place probably a good idea that it is discombobulated!
At least if it's some way that would you reuse stuff for other purposes or whatever at least you know which one is the one that's no good when it's been discombobulated.
I bet one or two times where I had some more parts and couldn't remember is that I had accidentally put the bad part with the good ones it happened the grab the bad one instead of one of the good ones.
That's when I started marking bad on anyting that was for sure no good.
Although sometimes things that are actually bad initially could be good for repurposing.
For instance dr. Sandra Lee a bad part but a park that was meant for something else entirely.
Welled up using a switch for an evaporative cooler for another application the idea that many switch Terminals and the combination of power switching.
Couldn't find another switch that was suitable.
Needed to be ready for 120 folds at about the same amperage.
Can't remember what the application was but it worked out great just World up scrubbing off the original labels on the switch plate using rub on transfers and then clear coating it.
Save me the trouble of trying to design something custom to control it.
And also make it simpler for the end-user as well just to turn a knob on the wall.
Gas in WDF18 is probably R22. This is a very common thermostat somplace, but not in EU.
Thermodynamics I love it!
Fan speed, Condenser temperature, evaporator temperature. And room ambient temperature all play a role
A single 555 or an op-amp can also be used to make a fridge thermostat (if you don't have a microcontroller based one). The only trouble is that a 3...5 minutes pause should be implemented between turn-on and turn-off.
That's why you use a 556.
@@Peter_S_ good point, Peter: use a 555 as timer for another 555
@@soupflood long delays with the 555 get a bit random, but that's tolerable for a compressor delay. I was recently looking at the oscillators of the Roland Jupiter-4 synthesizer who's arpeggiator was made famous by Duran Duran in Rio, and the oscillators actually use a 555 to trigger a reset of each oscillator period. What a great chip.
@@Peter_S_ i was still thinking about the one 555 delaying another 555, but that only works at power-up, not between each disconnect of the compressor after it reaches set temperature.
I guess only 555 can't maintain a delay between compressor cycles too, for example to avoid premature turn-on if the door has been opened right after compressor shut down.
@@soupflood Hmmm.. As a digital nerd, my first thought is usually, "is it cheating to add a couple 4000 series chips?", but I don't think it's necessary here. I think if you use the first 555 as a comparator where the output provides a little hysteresis via a feedback resistor and the discharge pin is otherwise floating, and then use the output of that 1st timer to trigger the 2nd timer wired as a delay where the discharge pin on the first timer is actually used to discharge the cap on the 2nd timer and the 2nd timer's discharge pin is left floating, you can end up with a comparator with hysteresis that triggers an RC delay to finally start the compressor after a delay which is retriggered any time its called to start. Maybe the connections for the delay would be a resistor from 555-A pin 3 to 555-A pin 7 and 555-B pin 6 to the cap to ground. If I had a 556 handy I would breadboard it.
TIL! I guess I assumed they worked off of electronics like using a thermistor or something to that effect. This makes more sense for a low-cost thermostat, like in a mini-fridge
I presume units with a digital temperature control use thermistors.
I've only had 'old-fashioned' fridges with the temperature knob and you can hear these click even when unplugged. If you notice conventional refrigerators also have a motorized defrost timer. If the compressor is off but you hear a slight ticking coming from the thermostat area chances are it's defrosting.
Panties wit wings or rather sanipads wit wings while horsing around...or like me, while cycling long distance !!!
At 12:30 I wanted to know what the liquid tasted like😉
BTW, not sure if it's still the case but fridge doors were held shut by magnet strips inside the door seal
That's still how they work. My understanding is before they added the magnets you needed to manually latch the door shut.
I think the first one is for fridges mostly neofrost fridges and the 2nd one is for Windows ac because I've tried to use the 2nd one in some neofrost fridges and failed to perform accordingly.
I was today years old when I learned NOWIS is SIMON upside down.
Now you can get an electronic thermostat for 2dollars in china....it worked for two years very precise in my fridge.
That bellows / diaphragm is so shallow and flat because it needs a small volume.
After all, the themostat measures the average temperature of all the liquid.
Having too much volume in the themostat unit makes it sensitive to the temperature of the environment.
Hi,
As far as I know, the liquid inside the capillary tube is paraffin.
Cheers!
Clive, have you seen the new battery powered 2x LED COB lightswitch from Poundland? It has a slide potentiometer connected to minimal circutry to change the brightness, it has an integrated switch mechanism to cut power. Quite well designed actually, but disappointing the COB LEDs are smaller and have 8 diodes each on a single board instead of 10 diodes on individual boards like the previous one (I bought them for the components)
I'll keep a look out for that. The current will probably be giving the potentiometer a hard time.
@@bigclivedotcom That's what I thought until I looked at the SMD components on the underside of the circuitboard, 0ohm resistor (used as a jumper), 10ohm resistor, 470ohm resistor and a transistor. You'd look at the circuit and instantly figure out what's happening, to me it appears the slide potentiometer is adjusting the voltage going into the base of the transistor to change LED brightness. Should be a good teardown video when (if) you get one.
I would have used propane, and filled the vial half full, the pressure in the tube is directly proportional to the temp of the propane, as long as there's liquid in the tube it doesn't matter how full it is, it works the same.
I think some of those cap tubes contain refrigerant, which variety I am not sure. The one you cut open that had nothing in it probably had a whisp of refrigerant.
Not air filled as that you would have too many variables so it would be filled with a pure gas like nitrogen or a mixed gas where you have a known expansion rate.
People like us? Did you just assumed I'm technically inclined? #triggered
Possibly Glycerin as the oily substance?
Very interesting indeed.. Clive, you may have just saved my bacon here. re, the WDF18 type thermostat. Mine appears very similar a WDF27 variety. from a small LEC fridge freezer. It appeared to be faulty, so could not resist carefully taking it apart. I have only removed the bellows and switch, by bending the "panty wings" but now unable to get the bellows back in, as they are very extended, and have found that a lot of pressure is required to push them down again, " Unlike yours" I am concidering getting some freezer spray, inorder to make the bellows retract, so as I can get them back in again. But previously having bought a new one which I was told would be compatible, does not fix the problem. The switch is indeed a strange arrangement: C: Compressor H: Live L: to the light switch. Between C & H there is intially continuity, but as one pushed the centre pin down it becomes o/c until it clicks, where once again continuity is restored. Some very useful information here in video. Thank you.
Could it be that C is for compressor, H is for heater element (not installed in cheap refrigerator models) and L is for Line?
Still in common use all of this. The square one is a simmer stat used for catering trolleys. Some say there temperature range on the side.
When it turns out the capillary is filled with oil instead of alcohol you can hear the disappointment in the voice.
Oil? I thought there has to be a propylene glycol or something similar. And it is oily to the touch too.
I cut one of those open once and the liquid bust into smoke and flames as it dripped on to my tile floor.🥰
I believe the auto window openers on my greenhouse windows are filled with some sort of wax? wich expands and contracts in sunlight
@hob991 Check out Clive's video on wax motors - that's exactly what you have in your greenhouse by the sounds of it.
Plausible; some carburettors used wax motors for warmup choking. They tended to fail and be a pig. Thank you, Pierburg.
who else thought it was from a person called nomis. lol love the videos clive keem em comming.
I've seen things of this sort also used to regulate the temperature of an oven...
The capillary tube might add delay/hysterisis to the sensor?
👋👋👋👋👋 for the clickety click discovery of the century 😝
could you show in a diagram how the screws adjust the chinese thermostat
Why is the defrost pin there in the first place? To be able to turn it off with the knob?
Great job....showing how NOT to go about disassembly where the goal is to understand how thing functions and how it may be re-assembled. Having one foot in a childish approach to something like this really wastes a viewer;s time.
I do put most things back together again afterwards, but this one was not getting reused.
I’m surprised it’s not just a thermocouple! Interesting.
A thermocouple would require a reference point with a known temperature, electronics to amplify the signal and detect if over/under the threshold and drive a relay or output thyristor plus a power supply. These traditional mechanical units avoid all that and can even regulate non-electric devices such as open flame gas owens.