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  • Alto-Shaam Combi 20-20 Gas

  • guest

    November 8, 2017 at 12:00 am

    God knows I am going to regret asking, but I just got off phone with one of my clients who “claims” their 1 year old Alto 20-20 gas combi overheated causing the glass panels to explode? Ugh, 35 years and I have never ever heard of or seen this happen, personally think they stuffed doors on dolly or ran into unit and dont want to fess up, has anyone here ever heard of this happening? Please be gentle.

  • john

    November 8, 2017 at 5:29 pm

    I just don’t see it as likely. Alto Shaam makes a quality product, and from my understanding of Combitherm ovens, they aren’t under pressure like a traditional steamer–thus glass panels instead of a steel door.


    Plus, wouldn’t the gasket fail before glass panels exploded? Aren’t there multiple safety mechanisms to prevent such a possibility?


    Something seems off to me, but I guess anything is possible. I’m curious to see how this develops. Keep us posted!

  • ectofix

    November 8, 2017 at 5:38 pm

    I have no Alto-Shaams, but about twenty-six Rationals.  I’ve dealt with broken glass several times.  Always a full-size floor model like yours.  Almost ALL occasions was from having a mis-matched trolley crammed into the wrong oven (we once had numerous different sized ovens in one kitchen).  The one other occasion?  Nobody had an explanation (of course).


    I don’t think they’ll break from overheating since there’s a cabinet high-limit to prevent those ovens from heating above 650°.  I’m not absolutely certain, but I believe the glass is good to over 1000°.

    The high-limit is designed to be fail-safe, which means that if DOES fail, its contacts open.  Therefore the oven is disabled when that happens. 

    By virtue of their design and application, that’s REALLY the only direction a high-limit will fail.  I have NEVER heard of a high-limit sticking closed.

  • fixbear

    November 8, 2017 at 7:16 pm

    The glass in a oven door is very special.  It is tempered and thermally cycled to prevent breakage form normal use.  I only know a a few things that will break it.


    1)  Mechanical hit of about 1800 lb’s per square inch.  In other words, something pointed or concentrated in a small area.


    2)  A thermal shock to very hot glass like ice cold water to one area.


    3)  Tension stress from mounting or severe twist in a door frame.


    If you really want to know you can always collect all the pieces and have a puzzle party.

  • ares

    November 8, 2017 at 7:44 pm

    Yeah, thank you all, I am sure it was caused by crammed dolly, and I am also as sure nobody is going to admit to it, I shudder to think of the next day air shipping cost of the glass panels, I have a 12 year old unit which is still purring like a kitten at another “similar” type of location, I know were not suppose to take these types of calls personal, but I still do every single time. Defies logic how customers figure out new ways almost daily to do the unthinkable. 

  • ares

    November 9, 2017 at 4:53 pm

    Ok, so I made it out to client today, the unit they said overheated was actually smashed by one of the cooks slamming door closed onto trolley. I spent over an hour on phone with Rational trying to get the correct part number for the inner door pane. They literally could not find it, she wasn’t very helpful. This unit is approximately 6 months old, it is a Rational, not an Alto as I was told on previous call, it is a model SCCWE202G, and unlike older units I have worked on this unit has the main outer door, & “2” inner glass panels which clip to the m

    ain door. The Rational rep told me I had to purchase a part number 87.01.415 Glass Pane Bundle, which apparently is both of the swinging inner glass panels, which seems a bit ridiculous as I only need the very inner panel. This being such a new unit, I imagine there hasnt been a whole lot of experience with them. Do any of you know if this is truly the case or have you been able to but a single inner panel? Thanks in advance. 

  • olivero

    November 9, 2017 at 5:16 pm

    I’ll join in on this one.


    I once had a Convotherm oven overheat, really bad actually, totaled the oven but the glass held. I doubt this has anything to do with heat, since someone admitted to doing it, I guess that solves it.


    There ARE multiple safeties in the unit to prevent it from breaking the glass, most won’t go any higher than 600*F before they stop themselves, then there are cases where software is faulty or contacts weld shut and it won’t shut off but I think these guys thought with it, I think the only thing that CAN cause a combi oven to overheat, is software malfunction. Thinking about it, even if a contact welded closed, the safety would open and there would be no more juice being fed to the component so it can still be closed but there is no juice.


    So there you go, its extremely unlikely it was due to overheating and as you found out, it wasn’t.

  • ares

    November 9, 2017 at 6:03 pm

    I dont know if you caught my latest post, but have you had any of the latest build models with the 2 inner glass panes? Rational is telling me I have to buy the glass pane bundle, part 87.01.415 I am assuming it is both of the inner panes, which is odd as they only shattered the inner most pane.

  • ectofix

    November 9, 2017 at 8:56 pm

    I’m not a factory trained tech, but I’m well studied on Rationals.  We have so many of them that SOMEBODY had to become the duty expert.  I’m the demented person who did so.


    I don’t think Rational knows or understands how confusing their “way of things” or their application of model numbers can become SO confusing to you and I.  I had to weed through all of that and therefore bear more info about them than any “rational” person should…with regards to seemingly irrelevant constructive or historical details.


    So, are you SURE it’s a SCCWE202G?

    Here’s some TMI that I’m throwing at you which prompts that question:


    In the 5th digit of the oven’s serial number is a letter which denotes the oven’s version.  Here are the VERSIONS they made of the SCC (Self-Cooking Center) ovens.  You might also find the version to be denoted as the oven’s INDEX within their technical manuals:

    • INDEX E – an original SCC oven.  Began production in 2004.  Has a Cleanjet system using tablets.
    • INDEX F – There was none for the SCC.  Only the CM (CombiMaster) had a version F.
    • INDEX G – The version G ovens look just like the version E to the untrained eye, but has a drawer next to the hand shower for inserting CareTabs…made of citric acid.  CareTabs are fed in there to be dilute with water to then be pumped into the steam generator for a mild deliming process.
    • INDEX H – Had a new user interface (touch screen).  All new electronics.  Just about everything inside was new.  Still the original SCC cabinet, though.  Originally toted as the White-Efficiency (WE).  Later software upgrades would make it a 5 Senses (5S) oven.
    • INDEX I – They dropped the WE suffix from the model to just call them just the SCC again.  The “I” ovens incorporated LED lights in the doors, triple-paned glass…and I’m sure other upgrades.


    FWIW:  The letters A to D were used up during production of Rational’s CPC ovens – made until 2004.


    Rational went from version “H” to “I” in mid-2016.  The changes between the “H” and “I” are sketchy to me, since I don’t have an “I” oven.  Otherwise, I know of everything they made from 1994 to 2004 (the C-Lines and CPCs prior to the SCC) and all SCCs from 2004 until early 2016. 


    Since 1999, the serial numbers sixth & seventh/eighth & nineth digits indicates the year/month the oven was made (respectively).  So a serial number such as G22SH1602XXXXXXX would be a gas-fired 202-sized White-Efficiency oven made in Feb of 2016.  The seven Xs are just the numbered sequence of when they rolled out of the factory.


    Anyway.  Enough of that. 


    Just because they only had that oven for six months doesn’t mean its only six months old.  I say THAT because two of my newer ovens were already two years old when we got them. 


    So, the most important information you need in order to seek out a part for that oven is the serial number.  I’m sure that your “hour” with them on the phone brought that serial number up, so this information may be my own inaccuracy as an tech untrained by the factory and I need to learn more.  But…maybe the “irrational” info I’m providing here for their ovens up until 2016 will be helpful to you or others later on.


    I DID research Rational’s service partner portal by using an appropriate version “I” oven serial number format and looked at their on-line parts breakdown.  YES, that door glass is only offered as a bundle – part number 87.01.415.


    If the oven has a “G” in the fifth digit of the serial number, then you’ll only need a single-pane glass – part number 24.00.212.


    They are obviously not interchangeable.


    Either way, I’m certain that the price(s) will serve as their motivation to use greater care when loading an oven that has a predominantly glass door…which all combi-ovens do.




    For any further details on this matter, we need a badbozo2315 to show up here.

  • ares

    November 10, 2017 at 4:29 am

    Wow, you have spent some time on these, you could almost have a room with cutout pictures of rationals taped all over the walls like a rational stalker haha. I totally get it though as I am thorough to a fault, and determined to “mine” my way through complexity and confusion until I find a suitable answer. Too many techs and facility people jump at the first answer without thoroughly vetting what theyve been told, then end up chasing their tails only to end in endless returns of incorrect parts, frustration, and inevitably giving up. So I assume I will be stuck with an extra pane of glass after installing the “bundle”  and it would appear the panes are slightly offset in height so theyre not interchangeable.




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  • guest

    November 11, 2017 at 5:34 am

    I went to one of their four day classes. During the class they emphasized that we were NEVER to use any kind of  abrasive cleaning pads on any of the glass for any reason. This would include Scotch Brite type pads. They had found that these pads would create micro scratches in the tempered glass and, weaken it enough that when heated, would cause it to shatter/explode.

    As for that model number, if you have a SCC digital display, you can bring up the model number by touching  the  pad for the info and it will bring up the model and serial number. If you ever call Rational, you will find that they usually want the full model number. The serial number is secondary. Kinda like Hobart, They only want the ML number first.   

  • badbozo2315

    November 11, 2017 at 6:56 am

    >For any further details on this matter, we need a badbozo2315 to show up here.


    Huh? Wha? 


    >I have no Alto-Shaams, but about twenty-six Rationals.


    EC, I still don’t know how you sleep at night…   

    And if you’d stop taking the things down to bare metal, you’d have an exact count. 


    Just to add to the whole Rational thing, if you work on Rationals at all, you *need* the TechAssist app made by Rational for your tablet or phone. Type in your 7  digits of your serial number, and voila, all the info, and access to bulletins, manuals etc.

  • guest

    November 17, 2017 at 5:27 am

    Thanks badbozo2315. I didn’t know that they had come out with an app. I’ve been d/l the individual parts/wiring diagrams, to my cell. Another reason to make them buy me a tablet! LOL Walking two blocks back to my desk top, every time I need some info, gets old after awhile.

  • ares

    November 28, 2017 at 7:47 pm

    I am registered on Rational, looked everywhere but cannot locate the Tech Assist App? Can you advise? Thanks in advance.

  • badbozo2315

    November 29, 2017 at 6:19 pm

    >I am registered on Rational, looked everywhere but cannot locate the Tech Assist App? 


    Are you a trained certified Rational tech? We got an email with a QR code in it, that brings you to a certain page, to be able to install it. Give them a shout and I’m sure they’ll send you the link.

  • ectofix

    November 29, 2017 at 6:52 pm

    So, after you (and Matt.  A guy from your company

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