MBUv3 Repair

[mkcoen]

Anyone real familiar with working on these?

I have one that is showing an error code 6 which is "ER06 indicates a faulty vent valve assembly" I tried going through the TM to remedy the problem but one of the things you have to do is take the check valve off and then cycle through refilling. Problem is it won't get past the error code to let you do that.

I went ahead and removed the check valve and made sure it was opening and closing okay so don't believe that's the problem but the error code won't go away.

Beyond telling me to ditch it and get a M2 burner, any suggestions on actually fixing this one?

 

[mkcoen]

Okay, pulled the entire fuel and air system apart to make sure there were no blockages. After doing that I got the error message to go away but continued to get a "low fuel" light and would not start no matter how much fuel I put in it. Finally topped it completely off using the onboard fuel pump until that shut off and now I'm back to the original error message. I'm about to the point of trying to fire it up with a cutting torch and sawzall.

 

[kipman]

 

[SCSG-G4]

Haven't had that problem yet. But do make sure all electrical contacts are good (take apart, clean off, put back together). I have not seen a -24 or -35 manual for them, but maybe they are built to be sent back to the manufacturer, or sent to DRMO (flip a coin) when they break. I have spares and I carry them at the ratio of one spare for each three in operation. Most of my problems have been with the in-unit pump not being able to fill the unit unless the fuel can was almost level with the burner. Next most common opportunity is in starting the units.

 

[Stonepicker1]

TM 10-7310-281-13&P dated 17-MAY-2010 may be what you need.

 

[mkcoen]

TM 10-7310-281-13&P dated 17-MAY-2010 may be what you need.

That's what I'm using (although I don't think mines the 2010 edition). I followed all the trouble shooting guidelines and end up back at the beginning.

edit - checked this morning and mine is the May 2010 edition.

 

[Stonepicker1]

Page 0008 of the TM under "operator maintenance" Troubleshooting shows error code of ER06 meaning "fuel sensor" with a "suggested action of" Check fuel sensor connection and wiring, Check fuel sensor. or it could be the "connectors to the vent valve assembly"

 

[Crazyguypa]

I had a problem with some of my mbu100's, got several different error codes. Turned out to be the pump not rotating. Seems they sat for awhile and just needed to be rotated. There is a black cover on the back of the pump, take it off and rotate the shaft with a wrench and see if that fixes your problem.

 

[mkcoen]

Page 0008 of the TM under "operator maintenance" Troubleshooting shows error code of ER06 meaning "fuel sensor" with a "suggested action of" Check fuel sensor connection and wiring, Check fuel sensor. or it could be the "connectors to the vent valve assembly"

Apparently they have different error codes depending on where you look in the TM. This list is copied directly from my PDF file of the TM under "Malfunction Symptom - Burner Will Not Start."

The controller will display the following error codes for the condition of “Burner Will Not
Start Or Shuts Down During Operation.”
1. ER01 is a general fault condition of no flame detected.
2. ER02 indicates a supply voltage overvoltage fault.
3. ER03 indicates a power supply under voltage.
4. ER05 indicates a flame detected prior to start-up or improper electrical
grounding.
5. ER06 indicates a faulty vent valve assembly.
6. ER07 is an invalid key entry.
7. ER09 indicates that either the fuel solenoid valve or the vent solenoid valve on
the vent valve assembly have failed.
8. ER0A indicates that the air solenoid vent valve has failed.
9. ER11 indicates a bad compressor.
10. ER12 indicates the igniter has failed.
11. ER13 indicates a compressor connection or wiring malfunction.​

12. ER80, ER81, and ER82 indicate control panel malfunction

Then I checked the page Stonepicker directed me to and it has this:

ER06 Fuel sensor Check fuel sensor connection and wiring. Check fuel sensor
(I didn't copy the whole chart as it's a bit large).

So I guess now I need to go through and see how many different charts show how many differernt ERO6's there are.