Middleby Marshall HIGH TEMP ERROR: every thermocouple has dropped out
On the PS638 the message means every thermocouple probe has failed open, so the control has no temperature reading at all.
Mon–Sat, 8am–8pm
- Temperature and sensors
- Pizza oven thermostat and control repair
- Source: Middleby Marshall
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What HIGH TEMP ERROR
actually means.
On the PS638 the message means every thermocouple probe has failed open, so the control has no temperature reading at all. The PS640 gas manual adds that a PLC malfunction can cause it. The X-Series shows the same condition as ALL PROBES OPEN, with an alarm.
Middleby Marshall pizza oven display · also shown as High Temp Error, ALL PROBES OPEN
What to do when HIGH TEMP ERROR shows on the pizza ovenKind of codeTemperature and sensors
A probe is handing the controller a reading it cannot believe, or none at all: a deck or tunnel sensor coated in baked-on flour and grease, its lead chafed or scorched where it passes the heat, or a connector loosened by years of doors slamming. The oven then runs hot, stalls short of its setting or shuts the heat off to protect itself. Letting the oven cool and restarting it is reasonable; a sensor that still reads wrong sits behind a panel, and that is a visit.
Usually leads toPizza oven thermostat and control repair
Thermostats calibrated or replaced, probes, timers, boards and displays repaired, so the pizza oven holds the temperature the cooks set and shows the right number.
Shows up asPizza Oven Error Code on a Deck, Conveyor or Rapid-Cook Display
A pizza oven error code shows as letters or numbers on the display of a conveyor, deck or rapid-cook oven, a flashing light on its panel, or a message about ignition, heat, belt or airflow.
MakeMiddleby Marshall
A Middleby Marshall conveyor call is about the line: how many pies came out right before the belt slowed, stalled or the crust went pale.
SourceMiddleby Marshall PS638 electric and gas oven owner's operating and installation manual (74617 Rev G)
PS638 (74617) and PS640 gas (60251 Rev J) touch screen ovens print HIGH TEMP ERROR. X70G, X55G and X55GWB print ALL PROBES OPEN for the same event.
Before you book,
in this order.
Each step comes from Middleby Marshall's own guidance for HIGH TEMP ERROR on its pizza ovens. Follow it to the end: the last card says whether this is a visit.
Stop baking: without any probe reading the oven cannot hold a temperature.
On an X-Series, press Dismiss to silence the alarm, then turn the oven off.
Book a visit so the thermocouples, their wiring and the PLC can be tested.
Still there?
It usually turns into pizza oven thermostat and control repair. Book with the code and the model number.
What not to do
The name suggests an overheat, but the cause Middleby Marshall lists is lost probes or the PLC. A single failed probe on an X-Series shows PROBE # OPEN instead and lets the oven keep running.
What you may
notice with it.
The pizza oven problems HIGH TEMP ERROR tends to arrive with. Answer these at the pizza oven before anyone is booked.
All problems
Where HIGH TEMP ERROR usually leads
Pizza oven thermostat and control repair.
Middleby Marshall
pizza ovens.
A Middleby Marshall conveyor call is about the line: how many pies came out right before the belt slowed, stalled or the crust went pale.
Middleby Marshall pizza oven repairMore Middleby Marshall codes
Temperature and sensors on other makes
All 15 codes of this kind
In Middleby Marshall's own words
All thermocouple probes have failed
Every code on this site is taken from the manufacturer's documentation, never from a forum or a parts listing. PS638 (74617) and PS640 gas (60251 Rev J) touch screen ovens print HIGH TEMP ERROR. X70G, X55G and X55GWB print ALL PROBES OPEN for the same event.
Middleby Marshall HIGH TEMP ERROR pizza oven repair,
where we come out.
The same visit in every metro below: the code, the model number, and a diagnosis before any part is ordered.
All service areasTampa BayFL · 31 areas
Miami / South FloridaFL · 47 areas
New York MetroNY · 75 areas
HoustonTX · 36 areas
ChicagoIL · 50 areas
Los AngelesCA · 95 areas
San DiegoCA · 31 areas
Questions
about HIGH TEMP ERROR.
Can I clear HIGH TEMP ERROR myself?
Is my Middleby Marshall PS638 overheating when it shows HIGH TEMP ERROR?
Why would every probe fail at once on a PS640?
Is ALL PROBES OPEN on an X55 the same problem?
Back to your everyday
Still showing HIGH TEMP ERROR?
A booking with a code goes further when it has the code copied as shown, the model and serial from the rating plate, and a note on whether the oven still lights, heats or moves its belt. With those three, the office can match the likely part to your oven the same day.