4. If the barrel intake is blocked, it is recommended that the MAC155 Probe be returned to Mac Instruments Corp. for service. This is because the barrel assembly will have to be removed and disassembled in order to be cleaned, and this can only be done at the factory.
Page 69
The LED will also remain “On” until this condition is reached. Tank Heater The “Tank HTR” LED is on when power is applied to the tank heater. On MAC155L probes this LED will always be on. On MAC155H probes this LED is on when 120V AC power is applied to the tank heater and off when the tank is at operation temperature.
Need help?
Do you have a question about the MAC155L and is the answer not in the manual?
Questions and answers