Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove the pump connector
Measurement:
Test 1.
Measure the resistance between the Live and Neutral pins on the pump.
Expected resistance as per table below:
Test 2.
Measure the resistance between either the Live or Neutral pin on the pump to the Earth pin.
Expected resistance greater than 1Mohm.
Note.
A reading of O.L on test 2 is acceptable as this is greater than 1 MOhm.
Measure the resistance between the Live and Neutral pins on the pump.
Expected resistance as per table below:
| Appliance | Resistance Ohms (approx) | Modena 25C | 292 |
| Modena 27C | 292 |
| Modena 30C | 228 |
| Modena 32C | 228 |
| Ferroli T-ONE 25C | 292 |
| Ferroli T-ONE 30C | 228 |
Test 2.
Measure the resistance between either the Live or Neutral pin on the pump to the Earth pin.
Expected resistance greater than 1Mohm.
Note.
A reading of O.L on test 2 is acceptable as this is greater than 1 MOhm.
Isolate as per TOPs P4
and refit as necessary