Mueller Hydro-Guard HG-2, Operating Instructions Manual

11

HG-2 LOW-PROFILE DIRECT DISCHARGE UNIT

TROUBLESHOOTING THE PROGRAMMER 

Troubleshooting 

TROUBLESHOOTING THE UNIT

control knob Is open on the 
valve OR Check the pipes for 
obstructions OR Check the 
valve.

•  Check the water pressure at 

the unit. The pressure must be 
in the operating range of the 
solenoid and programmer (150 
psi maximum). If too high a 
PRV might need to be installed.

The Hydro-Guard Unit will not shut 
off:

Possible Causes

•  The solenoid is stuck In the 

open position.

•  Batteries weak or dead.
•  Connection loss from controller 

to solenoid.

•  The solenoid is loose or there 

is debris in the adapter.

•  There is a hole in or debris 

around the diaphragm.

If your Hydro-Guard Unit does not 
activate:

Possible Causes

•  Water pressure off or low.
•  Batteries weak or dead.
•  Connection loss from controller 

to solenoid.

•  Solenoid not working properly.
•  Obstruction In flow of water.
•  The water pressure is too high 

and the solenoid will not open.

Try this Correction

•  Check if curb stop is open.
•  Change batteries.
•  Check connections for 

corrosion, breaks, or lack 
of connection.

•  Run an electrical systems 

check. 

•  Check to make sure the flow 

•  The water pressure Is too high 

and the solenoid will not close.

Try this Correction

•  Run a manual flush for 1 

minute.

•  Change batteries.
•  Check connections for 

corrosion, breaks, or lack of 
connection.

•  Check the adapters and 

solenoid for debris. Run the 
electrical systems check.

•  Refer to valve troubleshooting 

for possible corrective 
measures.

•  Check the water pressure at 

the unit. The pressure must be 
in the operating range of the 
solenoid and programmer (150 
psi maximum). If too high a PRV 
might need to be installed.

PROBLEM CAUSE 

SOLUTION

Controller does not flush 
as desired

Water at main water supply is 
shut off

Battery dead

Replace battery

Battery dead

Replace battery

Controller improperly programmed

Check program and clock settings

Controller set to OFF

Set controller to desired program

Blank display

Water does not turn off

Overlapping programming

Review all programming and edit 
any program that is in conflict with 
desired off schedule
Clear all programming in memory 
and reset

Programmer not communicating

Check Programming
Run Manual On / Off with solenoid 
removed from valve (hold finger 
or object over solenoid plunger to 
prevent plunger from dislodging 
from solenoid body)
Check wiring for damage and 
connectors to ensure proper 
connection (red to red & black 
to black)

Check main supply valve