Watts 1170-M2, LF1170-M2, L1170-M2, LFL1170-M2
Troubleshooting Guide
Problem & Cause
A. Unable to reach required set point or set point difficult to set
A.1 Supply temperatures not within specified limits
A.2 Hot and cold supplies reversed
A.3 Filters are blocked by debris
B. Unable to achieve required flow
B.1 Too much pressure drop at fixture
B.2 Checks valve/filters blocked by debris
C. Valve does not maintain required temperature or temperature
changes over time
C.1 Fluctuation in supply pressures
C.2 Check valve/filters blocked by debris
C.3 Recirculation loop not piped properly
D. Discharge temperature too hot or cold
D.1 Valve not calibrated properly
E. Hot water from cold water tap or cold from hot
E.1 Check valves fouled
F. Valve is noisy
F.1 Water velocity is too high
F.2 Valve not sized properly
G. No flow from valve
G.1 Hot or cold water supply failure or shutoffs closed
G.2 Check valve/filters blocked by debris
H. Flow from valve fluctuates
H.1 Fluctuation in supply pressures
H.2 Check valve/filters blocked by debris
Answer
A.1 Check differential temperature between hot and cold supplies and
outlet 10°F (5.6°C) minimum required
A.2 Reinstall valve with supplies connected to marked inlets
A.3 Clean filters
B.1 Measure supply pressures and check against flow chart. Look for
restrictions in valve or piping
B.2 Clean check valves/filters
C.1 Stabilize water pressures with pressure regulating or
balancing valves
C.2 Clean check valves/filters
C.3 Pipe recirculated tempered water return so it connects
to hot water source and cold side of mixing valve
(see Product Guide for piping details)
D.1 Readjust valve temperature per installation instructions
E.1 Clean check valves/filters
F.1 Reduce water velocity with pressure regulating valves
F.2 Check flow required versus rated flow capacity of valve
G.1 Open shutoffs or restore hot and cold supply
G.2 Clean check valves and filters
H.1 Stabilize water pressure with pressure regulating valves
H.2 Clean check valves and filters
