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I’ve come to the conclusion that it appears the N line is not switched at all and the switch actually takes place on L1.
That’s exactly what’s shown on the schematic. You can see it really readily in the schematic on the LH side of the PDF tech sheet.
so if my cloths come out dirty i may suspect the recirc pump as one of the culprits,right?
That would be something to check, yes. An inop recirc pump won’t always generate a poor washing complaint– depends on the customer, some don’t notice. But you can still check it as part of your overall unit operations test in service mode.
“what excatly do you mean by RECICULATING THE WATER?
i didnt realy understand why the washing machin even needs to have this kind of extra pump”Like the name says, the recirc pump simply recirculates the water in the wash basket. The manufacturers use these in HE top load washer because their lower water use and using impellers instead of agitators means the clothes are not stirred as frequently during the wash cycle. The recirc pump helps improve water circulation around the clothes and to improve cleaning results.
“lasly,why over sudsing may bring about an extended spin cycle? ”
The excess suds can block the pressure dome with the air pressure tube making the control think there’s still water in the tub and extending the drain cycle.
” and when you said OUT OF BALLANC is one of the causes of extended cycle what did you mean by that? in other words what can cause out of ballance situation?”
If the washer control sense an imbalance during spin, it will ramp the spin speed down in an attempt to distribute the load more evenly. This usually works IF the imbalance is caused by unevenly distributed clothes. But if the imbalance is caused by something external, like one of the foot pads not being set down fully, then the washer will continually stall the spin cycle thus extending it.
“So the cam is controlling the bi-metal tension which controls the bi-metal ability to open/close the switch from current “heat” passing through it.”
Yes.
“That is some cool science/engineering.”
It’s very cool in its own micro-world way. I want to thank you for your question because it made me realize we needed more explanation in that unit. I’ve added some additional material there. Look it over and let me know what you think.
Keep in mind that the purpose of the video was to show you various water level sensing technology. The video was showing you examples of specifications. The associated control setting for the various frequencies and water levels may have been given elsewhere in the tech sheet but it was not shown or discussed because that’s not the point of the video. You will use whatever specs are given to you on the tech sheet/service manual. I showed you examples of those specs.
“If the switch is set to “low heat” or “simmer” to the element, the current traveling to the element through H2 L2 through the infinite switch is always going to be the same no matter if is is High Heat or Low Heat, correct? ”
Yes. But the current is being switched on and off according to the opening and closing of the bimetal. With the switch set to “high,” the bimetal stays longer, element stays on and hot longer. With the switch set to simmer, the bimetal stays open longer, may only close momentarily every couple os seconds, as an example. WHEN the bimetal is closed, the amps are the same regardless. But amps go to zero when the bimetal opens.
“What controls how long the bi-metal opens and closes and at what speed if the current is the same going through the bi-metal for the desired temperature? ”
The specific metals used in the bimetal and their thickness and length. It’s an arcane sub-genre of materials engineering. And the amount of tension the cam puts on the bimetal strip.
“So what does the cam do? What effect does it have on the bi-metal (if any) to open and close more often on/off longer or shorter cycles?”
The cam breaks the L1-H1 connection when the switch is in the off position. And it puts tension on the bimetal strip to adjust the how often it opens and closes. The cutaway view of the infinite switch in the video is shown in the off position.
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This reply was modified 2 years, 1 month ago by
Samurai Appliance Repair Man.
“but these settings STEAM RESET,STAEM SET, FOAM RESET,FOAM SET MAIN SET etc.. what are those ?
are those the settings imprinted on the machine ?”Yes, they’re what the customer sees on the control panel. They would be explained in the customer’s use and care guide and the service manual. That’s the main thing to know: where to go to get the info you need to troubleshoot.
“for example lets take the main set/2.85″/41.71 Hz i know my frequency but why should i know the inches if im not gonne measure the hight of the water anyway?”
You’re usually just going to eyeball the water level to see that it increases with each setting and that the frequency is in spec at each level. If you wanted to measure a water level, just use your tape measure.
“why are the amounts of water are given in inches rather than litters?”
Two reasons: 1) Because this is from a US model and we use Imperial units, not metric, and 2) inches is a measure is length (or height of the water in the tub); liters are a measure of volume (length x width x height). As the name says, the water LEVEL sensor is measuring the height of the water in the tub, not the volume of water in the tub. To convert to liters, in addition to the height of water in the tub, you need the circumference of the tub, NOT the basket, the tub which is outside the basket. This is not our job. That’s the manufacturer’s job and then they give us the specifications. Your job as a tech is to ensure that the equipment is operating in accordance with the manufacturer’s specifications. Use the specs. Trust the specs. And love the specs cuz that’s all you’ve got to work with.
“and how am i suppossed to messure those inches of water in order to know what frequency i should read on my meter?”
WHY would you want to measure the inches of water? The manufacturer is TELLING you what the frequency SHALL BE at a given setting. Period. THAT is your spec. THAT is what you test for.
” for example if my frequency is checked good when the machine is empty should i create another check point by filling a certian amount of water and make a comparison ”
Easy enough to do because you’re already right there is self test mode. Couple of button pushes and you’re testing frequency at another setting.
“how can i use those inches vs frequency and use them in practice ,to determin if my pressur switch is in specs?”
What’s the specification?
“(with LETTER P BELLOW IT )”
“P” is just the wire color, purple in this case.
“NTC SENSOR CAN FUNCTION without a PCB ?”
The ATC switch has a crude little thermistor reading and switch circuit built into it. If you break one open, you’ll see a little board inside the switch.
“THE W thet is smack dab in the middle is neutral to the ATC SWITCH?”
Yes. That’s the Neutral supply for the switch itself. It needs a power source to do its job of reading the thermistor and controlling the power supply to the valve coils.
“and what is the line(marked with P right bellow ) running from the ATC SENSOR to the left connecting to to wire underneath the water level switch,in aid of? what its fuction?”
That is the Line supply for the valve coils that the ATC switch is switching to turn the valves on or off.
Just to add.. while vacuum cannot damage the tubing with the tools we use, pressure definitely can. Sometimes, you’ll need to pressurize with nitrogen to find a leak. Don’t exceed 200 psi or you could damage to relatively more delicate aluminum evaporator tubing.
Hi Scott. Keep in mind that learning the actual process of doing sealed system repair is a manual skill that you acquire by practice. But before you do that, it’s good to get acquainted with the process. And that’s where online learning and videos can help. The real strength of this course is in understanding how sealed systems work, how to diagnose them, and how to troubleshoot the electrical and electronic systems in the refrigerator. Doing system system work is just following a procedure. Here’s the dirty secret of the trade: most techs who do sealed system repair don’t actually understand how sealed systems work! THAT is what we teach online.
” If a technician contaminates his equipment somehow someway by unknowingly evacuating a hybrid system is nitrogen used to uncontaminated the equipment like nitrogen is used to clean a sealed refrigerator system? ”
Many technicians will not work on contaminated systems because getting rid of the different oil– mineral oil vs. polyol ester oil– is not 100%.But blowing out the system with nitrogen is a commonly used technique to purge the tubing of air and oil.
“What is “sweep-charging” being a greenhorn they are using terms and not sure what they mean by that term. Explanation would be much appreciated.”
Pressurize the system with refrigerant and then release. Repeat three times. Was a good technique back in the day. It’s not used so much anymore today because of all the recovery regulations.
“The video is only explaining this procedure but not showing this process. ”
That’s all you need to know for this type of recovery. With R600a, you don’t need to recover anymore.
““If using a dial a charge “”heat”” it up to 30 “PSI” higher more than ambient temperature on the gauge”. How does a service technician heat “it” up??? They are showing a pressure gauge when they say “heat it up”. Confused.”
When you go to sealed system school or actually start doing sealed, you’ll use a digital scale instead of dial a gauge.
““be extremely careful not to touch the tank or the main valve while dumping the charge…..why? ”
What happens to the refrigerant when you dump a charge? It’s vaporizing (read: boiling) as it changes from liquid to vapor. As it does this, it sucks up vast amounts of energy from everything near it, including your hand. Same thing that happens inside an evaporator. So it frosts up and gets super cold.
” “First to start dumping the charge they show opening the valve on the charging tank. What about the charge valve port on the diaphragm does that need to be opened? What state is the charge port. Is it already open? Doesn’t mention anything about the charge port on the manifold. It then says “open ONLY the high side valve on the diaphragm and dump the measured charged through the high side””
Read the last part of what you wrote: “dump the measured charged through the high side.” How can the refrigerant charge get into the sealed system if the charging valve isn’t open?
“MST course referencing gauges and types of gauges? ”
The gauges don’t make the tech– the tech makes the gauges. Look around on Amazon and you’ll see you can spend big bucks on gauges. The reality is that the $40 set of analog gauges will work just as well as the $300 bluetooth digital gauges.
““If digital scales are used” What are the alternatives just dial gauges instead of digital weight gauges? Is digital weight more precise and preferred measuring system instead of dial gauges? Does it not matter just personal preference?”
Digital is the way to for measuring charge. You’ll especially need it for R600a systems where you weigh out the charge in GRAMS not OUNCES.
“There is no time mentioned “as soon as it hits 500 microns” all finished? Does it take 30 minutes as well to pull the system down to 500 microns or less? How long does it usually take, ”
The length of time of the pump down will vary with how much water has entered the system, as in the case of a low side leak. Could be anywhere from a few minutes to half an hour, sometimes more if the system has had air (and water) in it for a while. Gets all in the oil. It’s a mess. But you hit your 500 microns, close off the valve and watch your micron gauge for 30 minutes. Gotta hold 500 microns for 30 minutes before you charge the system.
“Can a service technician pull a sealed system down so much accidentally collapsing any of the sealed system tubing? Is that something to be concerned about?”
No way, no how. The hoses would collapse way before the metal tubing. Vacuum pumps can’t get anywhere near either event happening.
does it mean the rotor spins at some exact whole number multiple of frequency generated by the inverter?
Yes
if i were to measure the frequencies produced by the inverter what frequencies would i expect to see?
The voltage and frequency will both vary by the type of application (eg., front load washer vs. refrigerator). You’ll need to look in the manufacturer’s service manual for the expected ranges.
Is this explained later in the modules how to determine if the compressor is weak vs a leak?
I think we get into that in the thermodynamics webinar series. To determine abnormal, you have to know what normal is supposed to look like. In a normally operating sealed system, you should see 0 psig (maybe even a slight vacuum) on the low side and about 100 psig on the high side for a R-134a system.
To determine whether you’re dealing with a leak or a weak pump, you need to install valves and gauges. If the system is still holding a refrigerant charge or has had a low side leak, you’ll see an equalized pressure of about 30 psi on the high side and low side. A low side leak can suck air into the system and look similar on your gauges. If the system had a high side leak, there will be very low equalized pressure. You can also run the compressor and note the pressure difference.
In the case of low side leaks, it can be ambiguous to distinguish between a leak and a weak pump. In this case, evacuate and recharge the system then run it and note the pressures on the high and low sides. IF the compressor is working properly, your pressures should be normal. If they’re not– low side pressure too high, high side pressure too low– then you’re dealing with a weak pump.
as i understood a synchronous motor dosent have a start winding which is out of phaze with the main winding so what gives them the torque required to rotate the rotor?
Shaded pole motors don’t have them, either. Both shaded pole motors and synchro motors use permanent magnets in either the rotor or the stator to give the induced magnetic field something to push against and make the rotor spin. The trade off is that they are very low torque and inefficient. You can stop a shaded pole motor shaft with your fingers. Synchro motor only appear to have torque because the output shaft is connected to the motor rotor via a set of gears– a type pf transmission.
With most motors, you test them by running them. Use your cheater cord and hot wire the motor. Both shaded poles and synchros are 120 VAC motors. So cheat away! You should watch this webinar recording for more on that: https://appliantology.org/topic/72423-voltage-voltage-drop-loads-switches-jumpers-cheaters/
Ah, yes, that’s the graphical way of showing you that those switches are ganged together in one location. In this case, water temperature selector switch. Your instinct was correct! All those switches are packaged in a single, physical switch body that screws onto the console and gets a knob attached to it.
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This reply was modified 2 years, 1 month ago by
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