Whitfield Advantage II-T Control Panel Error Codes

[Q24Bubba]

Recently after pressing start my stove does not turn on. It either lights up #1 Red and #1, #2 Green LEDs or just shuts off. I have to unplug to reset the error code then repeat. Sometimes it takes several resets before the stove turns on and operates normally. I'm assuming that the control board is sensing something that is out of tolerance but I cannot find any documentation on the error codes.

 

[Ssyko]

these may be handy, i didn't see anything about error codes but there is a troubleshooting guide

 

[Q24Bubba]

I have to correct my first post. This is an Advantage Plus. The error code is all green LEDs. 1, 3 and 4. When I press start the fan starts but then immediately stops followed by the three LEDs. See the PIC and Video that I post.

 

[Stovensen]

Hello Q24Bubba, and welcome to the forum,

Thanks for posting the video of the start up issue on your stove. Very strange issue with the LEDs being lit in that order. Never seen it before.
Maybe it is, like you suggest, an error code. But if so, it must be a secret code to us normal consumers.The service manual has no info on error codes or how to interpret them.

But first of all: Let's think positive!

Your statement here is certainly good news:

Sometimes it takes several resets before the stove turns on and operates normally.

It confirms that most components in the stove are working perfectly.
Most likely it's the bypass relay that is ageing and showing signs of wear ( due to arcing in the internal contact set ). We've seen this issue so many times before on this forum. But not the mystical LED error code, though.

A reliable way to troubleshoot the bypass relay is to simulate exactly what it does, when it is energized by the control board during the 30 minute start up procedure. The relay simply delivers neutral to the entire stove during warm up, waiting for the low limit switch to close its contacts. Within this 30 min. period the low limit switch should have taken over, so that neutral is supplied via the low limit switch during normal operation.
All you have to do to simulate the function of the bypass relay is to temporarily jump the low limit switch ( only temporarily ! ) This is easy: Simply connect the terminals on the switch together by a jumper wire.

Caution: Unplug stove as the first thing! The terminals on the low limit switch carry full line voltage ( 120 vac/60Hz ).

Jumper wire:

The low limit switch is located on the combustion blower housing ( the component with yellow wires on the pic )


Q24Bubba, with the low limit switch jumped, does your stove start up as it should?

Good luck and take care. Keep us posted

 

[Q24Bubba]

The plot thickens. I put the jumper across the the low limit switch and when I aplugged the stove in it responded differently almost every time. Sometimes nothing would happen other times all the green LEDs would turn on but only the combustion fan would blow. The convection fan only has 26VAC going to it. I'm pretty sure the control board is bad. The fan tested fine on my bench. Does anyone have a schematic for the circuit card assembly or know of a repair shop. I don't see anything on the CCA that warrants paying $400 for a replacement.

 

[Stovensen]

I put the jumper across the the low limit switch and when I aplugged the stove in it responded differently almost every time. Sometimes nothing would happen other times all the green LEDs would turn on but only the combustion fan would blow.

So with the low limit switch jumped, the stove is reacting very differently than before?
In your first post you stated: "Sometimes it takes several resets before the stove turns on and operates normally"
Doesn't it run normally now in any start attempts with the LL-switch jumped?

The convection fan only has 26VAC going to it. I'm pretty sure the control board is bad.

Before condemning the control board you should inspect the wiring and especially the Molex plug closely. If there's an oxide layer on the pins in the Molex this could be the source of the issue. Easy to clean the Molex plug with some contact spray. Unplug/replug the Molex a handful of times with the pins all wet with cleaner.

There are several repair services on the internet. A couple of examples:
(broken link removed to https://www.kijiji.ca/v-heater-humidifier-dehumidifier/peterborough/whitfield-advantage-ii-t-iii-plus-control-board-repair-service/265783976)

http://pelletstovecontrollerrepair.com/

Does anyone have a schematic for the circuit card assembly

We are many that have been searching for the schematics for the Whitfield control boards for years with no luck. Only way to get the original schematic would be to send an email to the manufacturer and ask them friendly if its available. The technology is 20+ years old and outdated, so who knows? Worst thing that could happen would be the answer: No

 

[Q24Bubba]

I hadn't use the stove in a couple of days because the temps had warmed up. my mistake. When I press start the fan kicked in followed by a thump thump sound. This is why I verified that the convection fan is still working properly outside of the stove. With the LL switch jumped the system would turn on automatically as soon as it was plugged in, not turn on at all, start to initialize then cut off, show all five green convection fans LED lit and the combustion fan would run. There were other odd behaviors as well.
Do I need to remove the relay from the circuit w/ the jumper in play? If so could you tell me where the relay is location or what does it look like?
Thank you for the links. The cheapest I could find was $185 in Alabama if indeed I need to repair the board.
I will go through all the connections again today to make sure they are clean and seated properly.
Thank you for your help.

 

[Stovensen]

With the LL switch jumped the system would turn on automatically as soon as it was plugged in, not turn on at all,

If jumping the LL-switch doesn't cure the start up issue, the bypass relay cannot be the culprit.
Only suggestion I can come up with now is a missing thermostat jumper ( or it has a bad connection ). If the thermostat jumper is missing, the stove will be in permanent idle mode and the controls on the panel will be inoperative. In idle mode the stove will be waiting for a "call for heat" signal from an external thermostat.
Electrically this call for heat signal is simply the thermostat closing its contact=making a short. The jumper does exactly the same thing: It puts the stove in permanent call for heat mode and the controls are active.

Thermostat jumper on control board:

 

[Q24Bubba]

I double checked the jumper and it was good. I found that the red wire pin was unseated in one of the Molex connectors but that did not fix any of the problems. Yesterday I took the control board into work to do a little troubleshooting and reverse engineering where I discovered that Vcc going to the A/D and the other logic chip was low, 4.6V. Turns out those chips have a minimum of 4.75 and a max of 5.5VDC on Vcc. The -5VDC linear voltage regulator had 16V on the input and 4.6V on the output. Thought it was being loaded down somewhere but could not find a bad component. I added a 5VDC power supply to the board to boost the voltage and the board appears to be more stable now. Although I'm not sure this is the fix until I replace the voltage regulator and put the control board back into the system. Parts are on order. I'll let you know. As for a schematic I think I've mapped out about 40% off the CCA. It's not very complicated but identifying all the components is a little tricky w/o taking parts off. Again, thank you for your help. Hopefully this will fix my issues.

 

[Q24Bubba]

I double checked the jumper and it was good. I found that the red wire pin was unseated in one of the Molex connectors but that did not fix any of the problems. Yesterday I took the control board into work to do a little troubleshooting and reverse engineering where I discovered that Vcc going to the A/D and the other logic chip was low, 4.6V. Turns out those chips have a minimum of 4.75 and a max of 5.5VDC on Vcc. The -5VDC linear voltage regulator had 16V on the input and 4.6V on the output. Thought it was being loaded down somewhere but could not find a bad component. I added a 5VDC power supply to the board to boost the voltage and the board appears to be more stable now. Although I'm not sure this is the fix until I the voltage regulator and put the control board back into the system. Parts are on order. I'll let you know. As for a schematic I think I've mapped out about 40% off the CCA. It's not very complicated but identifying all the components is a little tricky w/o taking parts off. Again, thank you for your help. Hopefully this will fix my issues.

Follow up..... After replacing the L95L05 Linear Voltage regulator (see image) the -5V bus rose from -4.6 to -4.8V and the control board appeared to be working normal. In an attempt to increase the performance of the regulator we tacked on 1uF surface mount capacitors on each of the existing voltage regulation caps across Vcc (see pic). We saw some improvement but -4.8V is still low so my friend (and the guy who did most of the work) is looking for a better voltage regulator. For now my stove is back up and running strong.

 

[Ssyko]

You have a data sheet on that LVR? I cant find a thing on L95L05.

 

[Q24Bubba]

Look up LM79L05.
The important thing d to find a 79L05. They are 0.41 on digikey.
I think the first letters are the OEM. Sorry for the missinformation. I should have referred to my notes.

 

[Stovensen]

For now my stove is back up and running strong.

Congratulations. Well done! Now enjoy the heat.

-4.8V is still low so my friend (and the guy who did most of the work) is looking for a better voltage regulator.

Reverse engineering is fun. My control board has to be a newer version than yours in that most components are surface mounted types.
And the voltage regulator is an LM7805 positive type. See pic of my control board below.
LM7805 can handle ten times more current than LM79L05.( 1 amp vs. 100 milliamps )
Maybe the voltage regulator on your board is loaded close to its limits?
It all adds up: ten LEDs + LED driver ic + microcontroller.
The Zettler bypass relay needs at least 24 Vdc to be energized. I wonder where it gets that voltage from? Let's see, next to the four rectifier diodes there's a zener diode. Maybe this zener diode is stabilizing the voltage for the relay? A relay driver transistor must be present too. This transistor is turned on by a data output from the microcontroller. A clamping diode across the relay coil has to be present to protect the driver transistor when the relay is turned off ( induction of high reverse voltage ).
The zener diode gets hot. We can see that the area next to it is darkened by the heat
Did you notice what voltage was written on the zener diode?

Control board in my 1998 Whitfield Quest Plus:

 

[Q24Bubba]

During troubleshooting we hooked up a power supply that could control voltgage and current. We limited the current to 100mA and set the voltage to 5V. This is how we determined that if we bumped up the voltage the board would work. Using the same test equipment we measured the current through the circuit and it never went above 10mA. We thought for sure something was pulling the VLR down but it just turns out to be poor voltage regulation. We measured 17V at the zener diode with 12v being dumped across a 330 ohm resistor. Both got fairly warm. The secondary of the transformer outputs 34Vac. The full wave rectifier turns that into the 17Vdc that hits the zener. The other rectifier creates 24Vdc used to power an external thermostat. No uC on this board. Fan and auger speeds are controlled by the two SCRs located on the edge of the board.

 

[JLoft]

I'll resurrect this thread because I have new info. I too had the intermittent power up problem that Q24Bubba had (hey, thanks for all the research you did!) until it got to the point where the stove would not start at all. The control board had the exact same symptom - only -4.64V coming out of the LM79L05 voltage regulator.

The fix was not the regulator. It was the electrolytic filter capacitor next to the regulator. Look at the first picture in post #10 above. See the cylindrical blue cap to the left of the circled regulator? That's it. 220uF, 25V. If you look super, super carefully you will see the top is ever so slightly bulged. The sign of a blown cap. In the 1990's and 2000's there was a flood of marginal electrolytic caps coming from China.

I put in a new 220uF, 50V cap (it was what I had laying around) and the voltage went to -4.97V. Perfect. The stove runs great again. i hope this can help others fix their control board for 50 cents, rather than a new board price.