Rheem RUUD AdvantagePlus - Low Water Cut-Off Switch Diagnostics; Low Water Cut-Off Activation Check; Low Water Cut-Off Continuity Test

AdvantagePlus Fault Tree Troubleshooting
1706.doc
5
Unit appears to be fine. Recycle power.
5. Is the low water cut
off switch working
properly? (It has power
going to it; so now we
are checking if the
switch has continuity.)
Yes
No
Disconnect green wire from vent overtemp switch. Leaving the
Molex connected at the low water cut off, check for continuity
between the two green wires at the low water cut off switch. If you
has continuity, then follow “yes”.
1. Disconnect the Molex and jumper the two green wires.
2. Recycle power.
3. If the unit goes to main burner, then replace low water cut off switch.
4. If the unit does not go to main burner, then recheck step # 4 above.
Fill unit with cold water. Recycle power and attempt to relight burner.
4. Is the low water cut
off switch activated?
(Make sure the tank is
full of water by bleeding
@ a gallon from a near
by hot water faucet.)
Yes
No
Verify 24VAC power from transformer
splice.
Recycle power and verify 24
VAC between the black and
red wires at the low water cut
off switch connection.