I am having trouble with my Rational SCC202 / 208 V

[coffeegeek]

It’s E11SG1106 so it’s a june 2011 🙂

I think I’ve mixed up the PCBs. There are two? I switched the dips on the PCB in the side compartment (see picture), not beneath the front panel. What does these dip switches do by the way?

[ectofix]

I honestly didn’t know that there were DIP switches on the I/O board, so just put them back as they were.

As for your other questions, I’ll see about addressing them tomorrow (if I’m allowed per Rational’s policies) – when my old and feeble mind is a little sharper.

Happy New Year!

[fixbear]

Never a good idea to change DIP switches without know the purpose they serve.  They can destroy things if set wrong in some machines. 

They are usually on a board so that the board can be used for different machines or models and options..

[fixbear]

Oh, and when you find one that is not what the manual say’s it should be,  You have to research why it is different and what it does before just changing it.

[coffeegeek]

I’m puzzled. There is a T-shaped hose connector (50.00.070) which connects the dual water supply connection (under the oven) directly to the hand shower at one connection and to 54.00.780 (the heated water compartment at the back left corner) with a solenoid in between on the other connection. Problem is the T-shape connector we have in our oven (actually numbered 50.00.077 not 50.00.070) is closed in the water supply direction. Is this just a dummy valve and is never actual supposed to supply water to neither hand shower nor the solenoid? Or did a previous service technician replace this valve by a mistake (especially since the part number does not match the parts list, neither 2009 nor the newest catalogue, still same number so I guess 50.00.070 have been unchanged all this time).

Also, non-return valves (50.00.078) in both outlets of water supply connection (8664.1301) seems to be missing.

Do you guys have any insight on this?

Maybe some also knows the correct function of 50.00.070 and 50.00.077?

[ectofix]

I don’t know why that part has 50.00.077 on it. That number doesn’t show up in ANY manuals or price lists (which I have copies of all the way back to 2006).

54.00.780 is simply the lid for the quench box. The SINGLE solenoid valve connected to IT is the quench valve.

The quench box is part of the oven’s drain system. Water supplied to it provides a spray of water to “quench” (condense) any steam escaping down the drain. The quench box has a motorized ball valve which remains open during the oven’s cooking functions. For cleaning of the oven, that ball valve closes during certain phases of the CleanJet cycle. As such, the quench box serves as a reservoir for the oven’s cleaning solution. The CleanJet pump drawns in that solution and blasts it into the rotating blower wheel to spray it around inside of the cooking compartment.

The non-return valves you asked about (50.00.078) were just check valves serving as anti-siphon devices. They were originally located within the water filters (Germany’s name strainer screens) inside of the water distribution T’s inlet.

Due to high failure rates of solenoid valves, Rational stopped installing those check valves in 2014. There was a modification instruction at that time on that subject. It instructs technicians to remove those check valves if they’re found in there during service calls. To do so, you gotta pry the strainer screen out of the T, slide out the check valve, then re-install the strainer screen.

FWI: Each solenoid valve comes with a strainer screen.  DON’T eliminate those (I’ve since corrected my prior statement on that topic in my earlier post).

If your local codes require a check valve, Rational recommends installing one at the water source tap.

As for your other concerns, here’s a graphic I threw together that might help:

[coffeegeek]

Thanks! 🙂

What about the 50.00.070? Does it have a built-in check valve? I removed it and now the hand shower works.

Still service 25, but i think I isolated the error to be a faulty PCB relay going to X19->Y2. When functional testing Y2, I can hear the relay click, but no 230V on the PCB test points or solenoid wires (probably burned contacts inside the relay). I’ll try with a generic 250V/10A (12V coil) relay I have, before ordering the original part.

[ectofix]

Didn’t I say I’m getting old and FEEBLE?  Gah!

Yes, the check valve was once part of 50.00.070 (and 071)…NOT the solenoid valves.  My bad.

I changed the typo after I posted that.

[coffeegeek]

Does anyone have the software repair program? I want to remove the PCB battery to reset the SRAM (see if it solves anything), but I’m afraid to have a non-operational oven if EEPROM carry inconsistent data.

[ectofix]

You’d be better served by calling Rational tech support about that.

I’ve removed the battery on version E and G units, but not on newer H & I ones.

I DO know that, in removing the battery on the older ones, all that happens is all the error codes and software updates are erased. But, I have a USB stick I’dordered from Rational (which I update on-line) that I use to get the ovens up-to-date again.

Perhaps @rationaltechnician or @badbozo can chime in on this one.

[ectofix]

BTW:

Can you please start a new thread for a new problem vice tacking a question onto a previously (presumed) resolved one. That makes things much easier at several levels.