Master temp E01 code

Apr 24, 2014
17
Oklahoma
Pool Size
13000
I hate to start another mastertemp thread but I’m having issues. New to us pool. The heater would turn on and fire before but I never ran it long enough to tell if something was off. Anyway it ran for about 10 minutes then threw the code.

I bought a multimeter to test the temp sensor and it appears to be bad. I bought a cheap one on amazon and it gave the same reading and same code. I returned it and bought one from my local store and it too read unlimited ohms and didn’t work. What are the odds I got 2 bad sensors, or am I doing something wrong with my meter?

If I’m doing something wrong, is the control board the next step?
 
The "E01" code indicates an open water temperature sensor.

Show us pictures of how you are testing the temperature sensor.

An open water sensor can be a break in the wires. Check for any signs of rodents chewing on wires.

It is rarely the PCB although people go to that first.
 
The "E01" code indicates an open water temperature sensor.

Show us pictures of how you are testing the temperature sensor.

An open water sensor can be a break in the wires. Check for any signs of rodents chewing on wires.

It is rarely the PCB although people go to that first.
I’ll post a picture tomorrow. I am using the leads to test by putting the points in the holes on each lead on the sensor. I don’t have any alligator clips to use at the moment. I checked all of the wires and they look good. Everything is covered in dust and grime. I cleaned the pcb as best I could but everything appears to be in working order.
 
You may need to test both sensor wires for continuity between the sensor end and the board connector.
 
Well apparently I’m an idiot and I didn’t have it set to auto range when testing. I just tested this one again and it appears to be in working order.
Just a little update if anyone cares. I cleaned the pcb with contact cleaner and it fired up and ran for a few minutes. I’m working on getting the chemicals balanced so I didn’t want to put it in spa mode to let it run longer. Hopefully I can test it out further in a few days.