Manitowoc E21: temperature sensor T1 reading out of limits
Indigo heads carry four temperature sensors, numbered T1 to T4, on the lines around the compressor and evaporator.
Mon–Sat, 8am–8pm
- Sensors and bin control
- Ice machine bin control repair
- Source: Manitowoc
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What E21
actually means.
Indigo heads carry four temperature sensors, numbered T1 to T4, on the lines around the compressor and evaporator. The board averages each one every six seconds, and if one reads outside its valid band during pre-chill it logs the matching number, E21 for T1. An unplugged lead, a cracked sensor or a chafed wire are the usual causes, and the head loses part of its self-diagnosis until it is fixed.
Manitowoc ice machine display
What to do when E21 shows on the ice machineKind of codeSensors and bin control
A sensor is telling the board something that is not true: a bin control that reads full on an empty bin, or empty while ice spills over the top, a curtain switch stuck open, a temperature sensor out of range, or an eye on a dispenser that no longer sees the cup. Scale and slime on a probe or an ultrasonic sensor cause much of it. Clearing ice piled against the bin control is a safe first step; testing and replacing a sensor is a technician's.
Usually leads toIce machine bin control repair
The thermostat bulb, paddle, curtain switch or electronic eye that senses a full bin, adjusted or replaced so the machine stops and restarts on time.
Shows up asIce Machine Error Code or Flashing Light: What It Is Telling You
An ice machine error code may show as a number on a small display, a pattern of blinking lights on the control board, a colored light on the front, or a machine that stops with one indicator flashing.
MakeManitowoc
With a Manitowoc ice machine, the technician notes what the controls report and checks the bin control before opening the cycle for testing.
SourceManitowoc Indigo Series air, water and remote condenser ice machines technician's handbook (Part Number 000014794)
Indigo E-board and G-board heads; T1 to T4 map to E21 to E24 in the Event Log.
Before you book,
in this order.
Each step comes from Manitowoc's own guidance for E21 on its ice machines. Follow it to the end: the last card says whether this is a visit.
Note every E21 to E24 entry and its time, because the number tells a technician which sensor to test.
Keep the head running if it still makes ice; the sensor feeds diagnostics rather than the basic cycle.
Book a visit to test the sensor and its lead; the sensors sit inside the head near live parts.
Still there?
It usually turns into ice machine bin control repair. Book with the code and the model number.
What not to do
E21 is not a cooling system problem by itself; it only says the reading is impossible. Bin level sensors are a separate group, E25 to E27.
What you may
notice with it.
The ice machine problems E21 tends to arrive with. Answer these at the ice machine before anyone is booked.
All problems
Where E21 usually leads
Ice machine bin control repair.
Manitowoc
ice machines.
With a Manitowoc ice machine, the technician notes what the controls report and checks the bin control before opening the cycle for testing.
Manitowoc ice machine repairMore Manitowoc codes
All 15 Manitowoc codesSensors and bin control on other makes
Modular ice machine
An ice-making head set on top of a separate storage bin or drink dispenser, cooled by air, water or a condenser on the roof, turning out hundreds of pounds of cubes a day.
Undercounter ice machine
A self-contained ice machine that makes and stores its own ice under a bar, a service counter or a kitchen island, from commercial units to clear-ice models in large homes.
Nugget ice machine
An ice machine that freezes a thin layer inside a chilled cylinder and pushes it out with an auger as soft, chewable nuggets, for clinics, offices, hotels and large homes.
In Manitowoc's own words
E21 T1 Temperature Sensor Issue
Every code on this site is taken from the manufacturer's documentation, never from a forum or a parts listing. Indigo E-board and G-board heads; T1 to T4 map to E21 to E24 in the Event Log.
Manitowoc E21 ice machine 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 E21.
Can I clear E21 myself?
Does E21 stop my Manitowoc from making ice?
What is the difference between E21 and E24 on a Manitowoc?
Can I replace a Manitowoc temperature sensor myself?
Back to your everyday
Still showing E21?
A booking with a code goes further when it carries the light or code copied as it appeared, the model and serial off the data plate, and a word on whether cubes still fall into the bin. With those three in hand, our office can match the probable part to your machine the same afternoon.