Powers e420UCM Series Under-the-Counter Thermostatic Tempering Valves - Manual (Page 2)

1. The flow of water is less than desired…
• valves upstream from supply not fully open
• low supply pressures
• accumulation of lime deposits in hot water pipes, restricting
the flow of hot water
• checkstops not fully open
• clogged strainer screens in the checkstops
• clogged cartridge
2. Flow of water is completely shut off…
• valves upstream from supply completely closed
• failure of cold water supply pressure (the e420 Hydroguard
is designed to shut off on a cold water supply failure)
• checkstops completely closed
3. Flow is untempered hot or cold water…
• accumulation of lime deposits in hot water pipes, restricting
the flow of hot water
• thermostatic actuator failure; replace with new thermostatic
actuator
• hot and cold water supplies are connected to the wrong
ports
4. Maximum temperature specified for the e420 Hydro-guard
cannot be obtained…
• accumulation of lime deposits in hot water pipes,
-restricting the flow of hot water
• hot water supply temperature is too low
5. Variable discharge temperature occurs…
• extreme pressure variations in supply lines
• valve operating below minimum capacity requirements
Every Six Months: Check and adjust the temperature setting
(See No. 4 under "Servicing".)
Every Twelve Months:
1. Shut off water supply.
2. Open up checkstops (if any).
3. Clean strainers (if any) and check for free movement of
checkstop poppet.
4. Replace seals if cracked, cut, or worn.
5. Reassemble.
6. Adjust stem to desired temperature.
Adherence to these guidelines and recommendations promotes
safe product use and ensures proper valve performance.
1. Thermostatic water mixing valves are control devices which
must be cleaned and maintained on a regular basis. Powers
specifies periodic maintenance at least once a year or imme-
diately after any changes are made to the plumbing system.
Although annual cleaning is recommended, frequency of
cleaning depends on quality of local water conditions. Refer
to Preventive Maintenance below for recommended cleaning
procedure.
2. Quick closing valves may cause damage to the mixing valve
by creating shock waves. When the e420 Hydroguard supplies
tempered water to self-closing and/or solenoid valves, Powers
recommends use of a shock absorber (Powers Part No. 460-353)
on the discharge line. This protects the e420 Hydroguard valve
from damage.
3. Locate the valve as close as possible to outlet fixture to avoid
waste of energy and water except in applications where the
valve is used as a primary mixing valve to supply an entire build-
ing.
4. Correct valve sizing affects valve and system performance;
under or over-sizing of the mixing valve(s) can cause poor
operation and possibly injury.
Preventive Maintenance
n
Safety and Performance Guidelines
n
Troubleshooting
n
2
WARNING:
Always verify the maximum temperature set-
ting to the valve after any changes are made.
This should also be checked as a part of a
facilities maintenance/safety program.