Whirlpool 4door refridgerator won't cool

[Morley]

Hi,

I need tour help. I have a whirlpool wrx988sibm01 four door refrigerator. None of fhe compartments are cooling. Compressor isn't coming on.

I checked the compressor (VEGZ 7H) it checks out good. Equal 6.8ohm across all windings/ terminals. No continuity to ground for any of the terminals.

All fans appear to work. As soon as i turn on power

First, icemaker fan comes ON, then condensor fan comes ON, then after a while the icemaker fan goes OFF and top compartment fan comes ON. Then after a while the freezer evaporator fan comes ON. Once the condensor fan turns ON, it stays ON. But the compressor never comes ON.

Then i checked the inverter (W10154805; VCC3 1156 19 A 52):

It is receiving 110v. The control voltage reads 7.14vdc, is it too high. Your video spoke of 4-6vdc for control voltage.

I also checked the output voltage from the inverter. 3 being the bottom terminal in the upside down triangular configuration of terminals and G being ground. (inverter should be putting out 230v 53-153hz), can't tell if this is ac vs. dc and how to measure for this 230v reading, i.e. across which terminals etc. So measure what i could and here are my readings:

G-1 = 167vdc; G-2 = 154vdc; G-3 = 154vdc

1-2 = 317vdc; 1-3 = 317vdc; 2-3 = 0vdc

I looked for current draw on one of the 110v wire coming to inverter, it never went past 0.03Amps, consistent with the low power fans that came ON, but never the compressor.

Now, i am at my wits end, with no path to troubleshoot the issue. Can someone please help.

Thanks in advance to anyone willing and able to help me.

[Morley]

Also there is discoloration on the inverter box to indicate possible heat damage. I checked the pcb as well, no burn spots, damaged or broken leads for installed components on the board.

[Vance R]

The inverter should try to start the compressor there should have been at least 2 or 3 attempts. These would have been kind some current pulses.  Is or was the condenser choked? Condenser fan working? This makes the compressor / inverter work harder and usually burns out the inverter first or it maybe a locked compressor. Your at the point where you need to try a new inverter.

[Morley]

Hi Vance,

I watched the amp meter a couple of time for about 15min straight from power on to see exactly that, ie, to see if the inverter tries to start the compressor, but i didn't see any spike in amps. So concluded it didn't trie to start it. 

Regarding condenser fan, yes it comes on immediately on power on and stays on all through.

I wonder if 7.09-7.14v is too high for control voltage to the inverter. Any thoughts?

This leaves two things for me, i believe,

1. As you said, try another inverter

2. Test the defrost thermistor to see if it working correctly. I am thinking if it stuck on high, the controller may be thinking then its still in defrost cycle so not turning on the compressor by not sending the correct control voltage. Possible?

[Vance R]

1 hour ago, Morley said:

I wonder if 7.09-7.14v is too high for control voltage to the inverter. Any thoughts?

It should have tried to start. Voltage is alittle high, but something should have happened.

1. yes

2. Possible but not very likey. When the refrig has been off for awhile and is room temp inside and outside it will start up when plugged into power.

[Morley]

Hi Vance,

I replaced the inverter today. Good news the compressor turns ON now, however the evaporator coils are still not cooling. Compressor is getting warm/hot, and the small small coming out of compressor and going the condensor coil is warm, while the big tube is staying room temperature. This should be sweating, right.

Condensor fan is running straight out, the inside fan cycle through (icemaker, then top compartment and then the bottom freezer as usual, but not cooling.

What might it be now?

Thanks.

[Vance R]

Compressor running, all fans running, condenser clean. Since this a room temp start so defrost issue possible. Condenser warm, it should be at least 20 degrees over room temp. Time to tap the sealed system and get pressures.

[Morley]

Hi Vince,

I tapped the sealed system, and noticed the compressor was starving a little (guage in the vacuum zone), so added refrigerant to bring low side read ~2psi.

Still no cooling. The condensor is not getting 20deg warmer than room temp.

Could it be a blockage in the line to condensor?

Blockage in expansion valve going to the evaporator?

I have a reversing electric solenoid valve hookednup and controlled by the main board. What does this do? And something that could be the cause?

As always thank you for your guidance.

[Vance R]

9 hours ago, Morley said:

I have a reversing electric solenoid valve hookednup and controlled by the main board

It is a 3 way valve for directing the refrigerant to one evaporator at a time. At power up whirlpool refrigerator use the 3 way valve to shut off refrigerant flow to do a system pump down. After 3 to 5 minute it will open to one evaporator to start cooling. Think it is the refrigerator evaporator that gets cooled first then the board will move the valve to cool freezer.

Sounds like you just tapped the lowside - it was in a slight vacuum so you add some refrigerant and still no cooling.  Did you tap the highside? Or what was the lowside pressure with the system turned off for several minutes?

[Morley]

Yes, i did only tap the low side and witnessed the slight vaccum while running, and within the first 5min so likely when the 3way valve was shut off. Along i presume while i was still charging it have opened to engage the evaporator coil in the fridge/top section. I noticed no cooling in either top or bottom.

Could the 3way valve be not opening/switching at all? Besides replacement, which will requires chargedown, vacuum, recharge, what can i check on valve to see if it is really working?

Once its functionality is confirmed, blockage in the system would i believe the only remaining explanation.

[Vance R]

21 minutes ago, Morley said:

what can i check on valve to see if it is really working?

Put your hand on the valve and plug in refrig should feel it vibrate as it goes to home position. .  Can also put into diag mode and there is a step to check the valve.

[Morley]

Thanks do the hand test first.

What am i looking for once the unit is set in diagnostics mode (04, i believe)?

[Vance R]

Yes, think that is the correct step. 

[Morley]

I heard and felt the 3way valve clicking to presumably the closed position at both startup and when i selected the diagnostic mode(04).

However, i also held my hand on the valve for over 15min after normal startup (= NOT in diagnostic mode) and didn't hear it click, to open to the either freshfood/freezer evaporator.

Is there a diagnostic mode or an electrical check if the 3way valve is working properly to set to all three positions?

[Vance R]

Not directly, step 4 run the compressor and all fans. step the 3-way through home position, closed postion, one evap at a time and then open to both evaps. You can monitor temps with a probe, ir gun or thermistor voltages. With the wiring diagram you can ohm the winding of the coils. Voltage is only there when the board moves the the valve and is pulsing the windings. Should be around 12 vdc.