13 replies to this topic

[-=Xploitz=-]

Hello again everyone. Long time no see?

I have NEVER worked on a Viking fridge in my life, and Im at my wicks end. I bought this beautiful fridge for a steal cause the owner said it needed freon. So I assumed I would be doing some sealed system work and have me a great new fridge for my home for $100!!

Well, after I get it home, i plugged it in and waited. Bout 30 minutes passes and I go to open the fridge and freezer compartments and well...no cold air flow. So, i open the top to the fridge and get to look under its hood so to speak, and the condenser fan is running, but no compressor running.

Ok, so I then checked the evap fan and the other fansa and all the fans are on. Lights are on, and the push button cold control lights are all working..ice auger motor works too. Everything is working BUT the compressor.

My next logical step was to check out the compressor.

I expected to see a relay or overload or capacitor like Im use to in the field like when i work on common side by sides and freezer on tops, but ill be damned if this monster fridge doesnt have one..And it also has a power converter!!!! It converts 110 to 200 apparently, and the compressor is a 230v compressor. NEVER worked on this stuff before.

So..i took off the leads plugging onto the 3 compressor prongs and probed them. Very low voltage..less than a volt registered, and sometimes a volt or 2 would register, but no where even close to 230v range. usually 0.123 or something volts.

So I'm assuming this power inverter is at fault? Or something BEFORE the power converter? What controls the power converter? Does this power converter act as the relay and overload or something? How can I test the power converter? Ive NEVER done this kind of work before.

Maybe theres some sort of control board like the damn GE motherboards have that the compressor relay solder joints burned up?????????

Any help will be most helpful.

Viking fridge

Full model number DDSB423DSS

Edited by -=Xploitz=-, 20 October 2011 - 05:54 PM.

[KurtiusInterupptus]

The inverter on this is very much like the start device, except you can vary the speed of the compressor...
if the inverter is receiving voltage but no output and the compressor ohms good...
bad inverter.
Find the 120 vac from the high voltage board to the inverter ...compressor delays 5 minutes on these on startup so you wont see it immediately.

Edited by KurtiusInterupptus, 20 October 2011 - 06:45 PM.

[-=Xploitz=-]

I used the wrong terminology....

Its not the power inverter its called the "compressor electronic control unit...yet on this label it says

"input 115-127V~/50-60Hz" 3.3A 1/3 hp 1PH"
"Output 230V-53 TO 150Hz 3.3A 1/3 hp 3PH"

Im assuming this is some sort of inverter or converter??



ill check to see if its getting 115-127V delivered to it and see if 230V is its output after 5 minutes. I didnt know about the delay, however, after some time the condenser fan next to the compressor did kick in before I took the voltage readings........

[Budget Appliance Repair]

No need to mess with testing the hi-voltage output side, without being connected to the compressor I don't believe you would get any readings anyway, the inverter doesn't see the compressor so doesn't function, (I believe the inverter output is 230 VDC).

If you are getting 115-127 VAC into the inverter/compressor electronic control unit and the compressor windings don't show as open or shorted to ground, (all pins to compressor will be same ohm reading from one to any of the other two, these are 3 phase variable speed compressor motors. I don't know what the ohms reading is suppose to be but seem to remember something like 10-12 ohms between each winding). The other check to make is the low voltage control signal that is sent to the inverter which tells the inverter what Hz/speed to run the compressor, I don't know the specs on that either but believe you should be seeing somewhere around 2 to 5 VDC.

This is all from memory of what I've read here in the forums and in a tech manual for a KitchenAid SxS that uses the same basic inverter/3phase variable speed compressor system which I believe to be the same system you are dealing with on this Viking unit.

Do a little research in the forums or better yet get the service manual for the unit and it will have the specs to check for.

Edited by Budget Appliance Repair, 21 October 2011 - 05:59 AM.

[Budget Appliance Repair]

Ok, I went and got some info from the KitchenAid Tech aid for the variable speed compressors (KAR-12):

Viking wiring colors maybe different then in info below but this should give you enough info if you can't get the Viking manual.

COMPRESSOR
The main control board supplies a 5 vdc, peak-to-peak square wave, at 54 to 150 Hz, to the inverter board. A standard VOM will read approximately 2.5 vdc. The inverter board supplies the variable capacity compressor with three-phase 230 vac. Varying the frequency to the inverter board, and not the voltage, changes the speed of the compressor. The compressor can run at speeds of 1620 to 4500 rpm.

NOTE: It is not necessary, nor is it recommended, to test the output of the inverter board. While the compressor is running, its speed is continuously updated. Speed is determined after analyzing two factors:
• The difference between the actual temperature and the selected temperature settings.
• The rate of temperature change. Minimum compressor speed is based on the freezer’s selected temperature setting, as shown in the following chart.

COMPRESSOR PROTECTION
To protect the compressor and maintain efficiency, minimum compressor off time is programmed into the control. When the compressor turns off, a minimum of 7 minutes must elapse before allowing a restart. The inverter board utilizes a current limiting device and thermal protection that eliminates the need for a compressor mounted thermal protector.

COMPRESSOR & INVERTER TESTING
Refer to page 4-16 & 4-17 for the procedure for servicing the compressor and inverter.
1. Run the diagnostics tests (see page 6-1) and check for the proper operation of the compressor in step 05.
NOTE: If the compressor does not operate perform the following steps.
2. Connect power to the refrigerator and allow it to enter the “cooling” mode.
3. While the refrigerator is in the cooling mode, the inverter and main control board voltages should be as shown in the chart below.
4. Set the voltmeter to read the voltages shown in the chart.
• If the 3 to 6 volts DC is not present at the inverter red/white and red wires, check P7-3 and P7-8 on the main control board for 3 to 6 volts DC. If the voltage is not present, replace the main control board.
• If the 3 to 6 volts DC is present at the main control board, continue with step 5.
5. Unplug the refrigerator or disconnect the power.
6. Disconnect the wire connector going to the compressor.
7. Set the ohmmeter to the R x 1 scale.
8. Touch the meter leads to any two pins. The meter should indicate approximately 9 to 10 Ω. Check between each set of pins to test all three windings.
9. Set the ohmmeter to the highest scale.
10. Touch one meter lead to the cabinet ground and the other lead to each of the three compressor terminals. The meter should indicate an open circuit (infinite).

[Samurai Appliance Repair Man]

Some rules of thumb on these inverter units:

- the compressors on these units rarely fail; the inverter boards (aka., the compressor electronic unit-- same thing), on the other hand, fail frequently.

- Quick Test: if the inverter board is getting 120vac power supply and the compressor windings are good, the problem is almost guaranteed to be the board.

[-=Xploitz=-]

Great info you two! Thanks!!

I did my assessment of the boards and the compressor. First time doing 3 phase compressors with DC current.

Compressor prongs ....all 3 ohmed out to about 6.7-ish ohms.
All open in ground to prong test.

GOOD COMPRESSOR.

Now, that damned board is a different story. lololol


Concerning the "Compressor Electronic Control Unit"...........

It does receive 120 VAC at its terminals.
it does receive 3 VDC from the other board.

Output is often in the millivolts.



Assessment.............Bad "Compressor Electronic Control Unit" ?

I believe its the culprit.

Now ...hopefully u guys sell viking boards.


Here's pics of the "Compressor Electronic Control Unit".

I don't believe the capacitor is suppose to be bulged out at the top like the one on the left with the green dot on it in the pics has.

Also noted some brown stain on the plastic of the board. Not sure if its "fried" marks...no odd smells. Perhaps its just the foams residue that got heated up that this inverter touches???

Edited by -=Xploitz=-, 21 October 2011 - 10:13 AM.

[KurtiusInterupptus]

You two? What am I...chopped liver?
and no sorry, we don't sell viking parts...they are a bunch of tremendous ass-hats to work with and wont allow it.

Edited by KurtiusInterupptus, 21 October 2011 - 12:25 PM.

[Samurai Appliance Repair Man]

Kurtius, I think he was referring to you and Willie.

[-=Xploitz=-]

Actually, it was a type-o. I meant to say you 3. Kurtis, Willie and of course Samurai.

1,000 Apologies




BTW,

How can I tell exactly what went out on this board????

Edited by -=Xploitz=-, 21 October 2011 - 01:14 PM.

[Samurai Appliance Repair Man]

How can I tell exactly what went out on this board????

Unless you have the board schematic (manufacturer's top secret-- good luck finding one), signal generator, and oscilloscope OR there are visible burn spot(s), you really can't tell the exact failure on the board. The determination is made by measuring inputs and outputs.

[Scottthewolf]

I must be chopped liver too!

[kdog]

Or, Chopped Liver II

[Budget Appliance Repair]

It certainly wouldn't hurt to try and replace that capacitor, (it is obviously a problem with that giant bulgy end), shouldn't cost much either and it will either work or not.