Model Number: QT02224GNAX “low coolant level”

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Tham
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Got a service call for a Generac Unit
Model Number: QT02224GNAX
SERIAL NUMBER: 9319461
Description: OBS 22KW 2.4 120/208 3P NG AL
It uses a RTS automatic transfer switch
It has a ASSY CTRL PROGRAMMED controller

The customer issue is that the unit did not complete the test that they do monthly, I arrived to the site and made sure that they were properly doing the test and they were. Got to the unit and observed the controller screen that displayed “low coolant level” which after reviewing documentation will stop the unit if sensed. I checked the coolant level and it was full (to the brim). I replaced the probe with Generac parts set the date and time on this the controller then got a message on the controller display “ready to run” , after which I decided to pack my tools and run it after that, by the time I got my tools packed and viewed the controller display it had reverted back to the message “low coolant level”. So then I tried clearing the fault several times per user manual instructions, pulling the controller fuse and reseating connectors, resetting the time and date, giggled wire harness and had no luck or as I say “no joy” does anyone have any suggestions.
Chris
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Are you sure you replaced the correct sensor, and are you also sure that the radiator itself is full and not just the overflow bottle?
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Tham
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Yes to both questions I actually removed the radiator cap and viewed, and ended up parts wise getting two different probes and some sort of cable that had what appeared to be a block in- line with the connector, I just used the the probe that matched the old one aesthetically, I’m pretty sure I checked the part number on the box but can double check it against what I pulled out if the number is on it. The probes were aesthetically different only one matched the old one
Tham
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Ok the part I put in was the matched aesthetically was 0H1827 but it appears that one according to my parts list should be used with that cable in - line block part number 0H1851, the other probe is a part number 0E2507 does appear to need that cable
Tham
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Sorry part number 0E2507 doesn’t appear to need that cable
Chris
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The unit shipped with 0H1827 and only that probe will work in its place on this unit.
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"The only source of knowledge is experience" -Albert Einstein
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grsthegreat
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did the homeowner drain and replace radiator fluid? i have heard for a few people that a type of vapor lock can occur in these units. generac actually put out an addendum on proper way to refill units.
Tham
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Ok I can see how the block (ASSY PCB LCL SENSOR) connects to the probe and the existing connector but there also another single extended yellow wire from the block (ASSY PCB LCL SENSOR) that is labeled 14 where does that connect (Ground ??? and or where???)
Chris
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This gen doesn't use that kit you're talking about at all, that's for R panel units. It just gets the sender unit and nothing more (just like it was before you started)
Generac tech for over 12 years. I'm here to help!
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