DHW THERMISTOR

Set Multimeter to Resistance

Isolate Mains Power to appliance as per TOPs P4
Disconnect the hot water thermistor at its inline connector

Measure the resistance across terminals of the inline connector that runs to the thermistor in the hydraulic block.

Resistances vary with temperature and should conform approximately to the table below:

Note: Clicking on the resistance table will switch between table and graph view.

Note:
There are two types of thermistor that may be fitted but the resistance readings are the same for both.