U.S. stove Model 4840 number 4 Flashes

[zinger827]

Hi I have a U.S. stove Model 4840 I just bought on Craigslist.
The problem I'm having is the number 4 on Control panel Flashes constantly as soon as plug it in?
I hit the On button to start stove and the Exhuast fan starts and runs but Auger doesn't move and not sure if Ignitor is getting power?
I can adjust heat setting on panel from 1-5 but the #4 keeps on Flashing no matter where Heat setting it is set to?
I open Hopper door or Front door and panel shows they are ajar when Stove is On.
I called US Stove they had no idea said to check molex connector wires to see if getting power there which the Exhaust blower side is anyway.
So maybe have to see if have bad wire?
I can't find this problem on this model or the 2400 eco aire which has same control board anywhere.
Thanks.

Oh and person on Phone from US Stove said sounds like Control Board is good. I Hope So!

 

[Lake Girl]

How well are the exhaust pathways cleaned out within the stove especially since used? Compressed air outside is the best way to accomplish it.

Did USSC tell you what 4 flash means as it is not in the manual?

Auger is not clogged? Auger will not move if vacuum not generated . Vacuum switch functioning, tubing not cracked or broken and port is clear? Door gaskets pass the dollar bill test?

 

[lhuffhines]

OP, Try checking the wires to the R2 Sensor. this is on the exhaust and is a proof of fire type sensor. check the wires from it to the board. it plugs where it is labeled Pressure.


Likely not a pressure switch issue since it senses the door opening. the pressure switch is part of the microswitch circuit.

 

[zinger827]

View attachment 190443[/QUOTE]

How well are the exhaust pathways cleaned out within the stove especially since used? Compressed air outside is the best way to accomplish it.

Did USSC tell you what 4 flash means as it is not in the manual?

Auger is not clogged? Auger will not move if vacuum not generated . Vacuum switch functioning, tubing not cracked or broken and port is clear? Door gaskets pass the dollar bill test?

Hi USSC didn't have anything to tell me when looked up 4 flashes constantly Lady said POF or Auger jam which she said doesn't sound right.
Vacuum good as after about 1 minute of turning unit on the Auger runs for 3 minutes I timed it.
Stove is cleaned right thru to Exhaust as the Exhaust fan is new just replaced this year.
Door gasket good.
Thanks for help.

OP, Try checking the wires to the R2 Sensor. this is on the exhaust and is a proof of fire type sensor. check the wires from it to the board. it plugs where it is labeled Pressure.


Likely not a pressure switch issue since it senses the door opening. the pressure switch is part of the microswitch circuit.

View attachment 190443

I tried hooking that wire to the Pressure side and stove instantly started all fans started blowing. So I switched it back to Stat side.and fans stay off but 4 blinks and red light to off button stays on until I hit On button.
I did notice when starting stove after about 1 minute the Auger comes on for 3 minutes as I timed it but the Ignitor don't get any power to it.
I did plug in a cord to Ignitor to test it and Ignitor is good as it got very hot.
When I got stove there was a Jumper on the Pressure switch post's.
I tried putting the other RTD to the Pressure post's but stove and fans came on as soon as I plugged stove in?
Haven;t hasd much time to play around with it but this is what I know so far.
I did start stove manually and once heated up the Blower room fan came on. The Auger came on Sporadically but not enough to keep stove running on it's own?
Thanks for help.

 

[zinger827]

Here is pic when plugged in the Off light is on solid and light on 4 is flashing but showing solid in between flashes.

 

[lhuffhines]

Call in Monday and speak to Ashton. Tell her you spoke to Lindsey. She can help you best.

sent from my pixelated Nexus 6p

 

[zinger827]

Ok I will. Thank you.

 

[zinger827]

Ok I spoke to Ashton and she thinks it's the RTD sensor on the Exhaust fan housing.
She said the 4 flashing means the RTD for Exhaust was not plugged in.
They cost $103 shipped?
She also said if it don't work I can send it back for Refund since there is a 30 day return?
Will have to order one and see what happens will keep post updated once I get part.

 

[zinger827]

Ok got stove running.
I replaced the RTD sensor to the Exhaust fan case.
First I diagnosed it before buying it as the sensor read 1000 ohm (the good one) so I made a jumper with a 1k resistor inline to mimic the sensor.
You can't use a regular jumper as it won't work needs to have around 1k ohm resistance to use as a jumper.
Once I put it inline the blinking light stopped and the stove fired up so I knew then it was the sensor didn't want to spend $100 on one not knowing.
So now I want to know how high the flame is suppose to be on low and then high setting.
I posted 2 pics one on low the other on high.
The stove once warmed right up throws out some pretty decent heat for what it is.
See pics stove on 1 and other stove on 5

 

[FirepotPete]

First I diagnosed it before buying it as the sensor read 1000 ohm (the good one) so I made a jumper with a 1k resistor inline to mimic the sensor.

Good trouble shooting! Let us know how it heats, I've always thought one would be great in my basement.

 

[zinger827]

Thanks hopefully it will help someone else down the road sometime.
I let it run all day in my uninsulated garage 12' x 30' about 30 degrees out all day and could feel difference outside and in so actually good little heater.
If in a Insulated room I'm pretty sure it will heat nicely.
I'm posting this stove on Craigslist as I buy them to fix and sell when good deals come up..
Otherwise I would have posted how it did.

 

[Lake Girl]

Thanks for the detail on the resistor on the jumper ... could help someone down the road with troubleshooting.