September 9th, 2015
I PERFORM A POST MORTEM ON A KITCHEN-AID REFRIGERATOR COMPRESSOR INVERTER
Lately, I’ve been seeing more inverter failures on inverter boards, especially on Kitchen-aid brands. An inverter is simply a device that takes 120 VAC in, then converts it into a DC voltage and chops it up into 3 phases. It’s there to make the EPA happy since they feel that our older style refrigerators with AC compressors are just too in-efficient.
The inverter refrigerators use variable speed compressors, so that the speeds vary according to the heat-load in the box. Ideally, such a compressor would run almost continually as a low speed setting to maintain correct temperature.
Here’s the inside of a typical inverter:
Of course, looking at the plastic case these electronics are encased in would give you no clue as to what happened, but if you were to open it up this gives an idea what’s up inside.
There’s a few ways to verify if the inverter has gone bad; First, is there 120 VAC to the inverter? Second, is there anywhere between 3 to 12 VDC to it? Third, do you have continuity of approx, 7 ohms between all 3 pins on the compressor? If so, its a pretty sure bet the inverter is bad.
These boards go from anywhere between $150 and $275. Conversely, if your refrigerator uses and older style AC Compressor, a typical start device (the counter-part of an inverter) is about 60 bucks. Its not as efficient as an inverter style box so you can expect to pay about $20 bucks per year to run it.
October 7th, 2014
Well it’s not all that interesting however I had another job involving a Whirlpool / Kitchen-aid / Kenmore branded refrigerator.
Complaint: Fresh Food box is warm but the Freezer is ok. If your refrigerator has electronic controls this problem is probably going to happen to you. If your refrigerator is older with mechanical controls you’re ok (lucky you).
Symptoms: Compressor is running; fans are running, but if you place your hand at the upper left rear corner of the fresh food box where the vent is located you will feel little or no airflow from the freezer section. The problem is that the motorized damper has failed.
The damper has a louvre that slides open and closed driven by a motor with an eccentric cam attached to it. This louvre has a ridiculously thin and fragile web of plastic that is driven open and closed by the motorized cam. It breaks with only the slightest resistance. I’m not really clear on why this louvre binds up but my best guess is that ice forms on the louvre and it “freezes” things in position and trying to force the louvre open or closed will cause that frail web to snap, rendering the mechanism useless.
I’m trying to figure out if this part can be fortified in any way to provide more strength so it wont snap as easily. I’ve discovered that this problem tends to surface when the humidity is high, or the door is left open for long periods of time, or the door seals aren’t sealing well. I’m really surprised that Whirlpool has let this design flaw go on as long as it has. Of course, it’s possible that the failure may be attributable to something else, such as a bad control module, or faulty thermister, or even a bad damper motor, but EVERY time is see this problem, THIS is what has happened.
September 3rd, 2014
A few weeks ago I had an informal lunch meeting with my Fisher and Paykel Tech rep Matt. He’s a young guy that comes from an appliance repair family. (His dad was a servicer and Matt got into it, following in Dad’s footsteps). So, over fish and chips and ale at Penny Lane in San Marcos, we amicably chatted about many things. We got along just peachy. Once the subject of honesty and integrity came up, Matt told me a tale that was amazing and I feel you all ought to know what happens out there.
This is a simple enough scam that reaps a “servicer” as much as $1000 a day without doing a thing!!!
Without naming names, these servicers are usually Russian or Ukranian. I don’t want to cast aspersions on a group as a whole, but from what I hear from my customers… well, to coin an old saying: “If the show fits, wear it.” I’ve heard enough horror tales from my customers about there guys and it seem they are invariably of that Geo-political suasion.
You call the company and they tell you their diagnostic or service fee is quite high (usually $75 to $95 dollars) They come out and (often without even opening up their tool bag) tell you it will cost you an OUTRAGEOUSLY ASTRONIMICAL fee to get it repaired.
You being a reasonable, rational and level headed person out of hand will reject the appraisal, you pay them their “fee” and they leave.
And that’s it. You’ve just been scammed.
Here’s the scam.
They (the servicers from the company) really had no intention of ever fixing your appliance from the get-go. In many cases, they have no skill or experience on your high end whateveritis.
ALL THEY WERE LOOKING FOR WAS THE SERVICE OR THE DIAGNOSTIC FEE that you paid them for coming out and “diagnosing” your problem. If they make 8-10 service calls each day, spending no more that about 15 minutes in your home, they’ve just made as much as $900 in a day for essentially doing nothing!
They make it a point to quote you an OUTRAGEOUS price to assure that you wont be calling them to fix your machine. And, even if you were ever foolish enough to actually have them fix the machine, you can bet on even money that they just won’t show up. I have heard this from my own customers.
But how on earth can they possibly survive in this age of social media and online reviews you may ask…
Well, these guys know that with this lousy “service” they provide, very negative reviews are bound to arise, but Aha! They are ahead of you there. They pay hefty sums of money to SEO (search engine optimization) companies to monitor their name and websites to constantly scrub and bury negative content on a daily basis.
What can you do to protect yourself from these pirates? Tough question. Check them out from top to bottom. Ask your friends. Call the BBB. Ask them a lot of questions and see if they seem to know what they’re talking about.
Sometimes you have to go by a gut feeling. I’ve often heard these guys described by my customers as arrogant, condescending, and rude. Often seeming to be in a rush to get out of the house with your check for their service call.
It’s a real shame these guys prey on unsuspecting customers. It gives the rest of us who are trying to provide honest service a bad name.
July 28th, 2014
As it is with just about all gas cooktops, the most common problem is difficulty in lighting. There are two types of ignition systems; Manual, and Auto-Relight. Manual is by far the more reliable of the two. Auto relight problems often stem from dirty cooktops, moisture from spill-overs, deteriorating sparking electrodes and faulty burner switches. This unit has manual relight and had problems with cracked electrodes and loose electrical connections. Once the unit is opened up the insides are all quite similar. It can sometimes be challenging to figure out how to open them up though since the manufacturers place their fasteners in different locations and occasionally the glass portion has to be pried up very carefully to avoid breaking it. While inside the unit, I always check the security of the screws holding the gas valves together, as they tend to back out over time. Once finished, I’ll check the burners lighting and look at the flame to be sure the fuel to air mixture is correct (about 1 to 16), evidenced by a clean blue flame all around with slight yellow tipping.
April 23rd, 2014
It was a typical ordinary service call in Carlsbad for a Bosch dishwasher that was stopping in mid cycle. The lady said somewhere in the cycle the machine would just go blank and stop, then start again and then stop and then on and on. I got there, put my clamp-meter on the main line power into the unit and started it up. Bosch dishwashers will energize their heating elements somewhere between 8 to 15 minutes into the wash cycle. When this happens the current jumps from 1.6 amps to about 11 amps as the heater draws significantly more current. (See my blog post on this page about bad solder joints on Bosch control modules)
Well anyway, around 9 minutes in, the current jumps up to 11 amps just as expected, but only a few moments after this occurring, the machine went dead. Lights went out, stopped working and after about 30 seconds or so, it started back up again, only to repeat the same cycle of going dead moments after the heater being energized. So AHA! the problem is in in the heater circuit I surmise. Excess current is causing the control module to shut down or so I thought…
So a new module in slapped in and we try it all again. But oh, No, it’s still happening! What can it be? What’s causing this machine to shut down when the heater kicks in?
Well, it took some time and a whole lot of thinking things through before I figured out what was wrong. These folks had one of those multiple outlet strip boxes under their sink. You know, those multiple outlet, surge protection boxes you get at Dixieline Hardware for 9 bucks? Their dishwasher was plugged into one of those. So after sheer desperation of trying everything else, I pulled the dishwashers plug out of the strip outlet and plugged it directly into the wall outlet and guess what? IT WORKED!
There was nothing at all wrong with the dishwasher. The strip outlet was faulty and would shut down when the current through it went higher. This caused the dishwasher to shut down and then start back up again as soon as the faulty strip outlet reset itself.
Sometimes its so easy to ignore the fundimentals when you’re out on a witch-hunt for the problem you ASSUME to be with the appliance.
Or try this one on for size…
Two days ago, a Fisher and Paykel Dish drawer Dishwasher. Lady said it wouldn’t do anything, no lights, nothing.
She was setting up the back end of an office suite for a studio rental. About halfway through I learn from her that she had new wiring and outlets installed and the dishwasher wasn’t doing anything. (now she tells me…) It was plugged into an outlet that supplied power to a Gaggenau two burner studio cooktop which was working. So as with all no power complaints I start at the source, and placed my pocket voltage probe
to the power line and it glowed, so naturally I presumed that the problem was inside the dishwasher, so start following the voltage trail till you hit the end right? Voltage inside the dishwasher was 62 VAC. Isn’t that odd? Shouldn’t it be 120 VAC instead? And curious that 62 is just about half of 120… Well, cut to the chase. Turns out that the household 120 VAC standard electrical wall outlet was defective, but only HALF of it was bad. The other half was running the cooktop with no problem. Prove it! Ok, Swap the plugs on the outlet. Now the dishwasher runs but the cooktop doesn’t. Had to be one for the books, A standard household electrical wall outlet that’s half bad. Close examination of the defective outlet showed nothing externally abnormal, Could have been installed by an electrical contractor or an inept husband and neither would have been the wiser. Oh and by the way, the cause was an open neutral line. I found this out using a wall outlet tester
Both of these nifty little devices are a must have for just about anybody that owns a home. It will pay for itself many times over, and they’re cheap; about 8 bucks each.