Troubleshooting Guide
LF1170C-M2 Series
Symptom
Cause
Solution
A. Fluctuating or erratic hot water
temperature at fixture.
A.1 Heavy draws of either cold or hot
water elsewhere in the system, such
as clothes washer or dishwasher
A.2 Unbalanced pressures
A.1 See warning on other side. Hot Water Temperature control Valves
cannot compensate for this condition. Check valves in hot and cold
leg to hot water temperature control valve would help but may not
cure the problem.
A.2 Install balancing or throttling valves (shutoff valves) in hot and cold
legs to hot water temperature control valve and adjust accordingly
for demand.
B. Hot water backing up into cold
water line.
B. Hot water pressure overriding cold
pressure
B. Examine inlet check valves for dirt or debris.
C. Cannot adjust water tempera-
ture to desired temperature.
C.1 Unequal pressures
C.2 Hot or cold temperature differential
C.3 Valve undersized
C.1 A balancing or throttling valve must be installed in the cold water
leg to the hot water temperature control valve to throttle or restrict
the pressure. In most installations, the cold water supply line
feeds both the hot water temperature control valve and the water
heater or tankless heater. To compensate for the pressure drop
through the heater, the hot water temperature control valve must be
throttled or reduced.
C.2 Check water heater controls to verify that the water temperature is
the same as the heater thermostat setting.
C.3 Check gpm flow required versus gpm flow capacity of valve
D. High pressure drop through hot
water temperature
control valve.
D.1 Valve undersized
D.1 Install larger hot water temperature control valve.
E. Insufficient hot water during
peak demand.
E.1 Valve undersized
E.2 Heater or heater capacity insufficient
for demand
E.1 Check gpm flow required during peak demand period and size hot
water temperature control valve accordingly.
F. Frequent failure of thermostatic
element.
F.1 Thermostatic element exposed to
extremely high temperature
F.2 Corrosive water conditions (buildup
of mineral deposits)
F.3 Electrolysis (pitting deterioration, etc.)
F.1 Check heater thermostat setting.
F.1a Hot water temperature control valve must be trapped at least 8” to
12” as shown in Fig. 2 on the reverse side. Install check valves as
recommended.
F.2 Frequent cleaning of thermostat element and plunger would tend
to prolong the life of the element. A small coating of FDA approved
silicone lubricant in the piston area of the element would also help.
F.3 Electrically ground the piping system or install
dielectric unions.
G. All hot or cold water flows at hot
fixture.
G.1 This problem will require consider-
able troubleshooting
G.1 Verify that complete installation instructions were followed:
G.1a is valve properly trapped?
G.2 Check to see if thermostatic element has failed.
G.3 Check to see if temperature control on water heater is set at
desired temperature.
G.4 Check to see if minimum flow requirements for valve size are met.
Minimum flow requirements for LF1170C-M2 is 0.5 gpm.
Limited Warranty:
Watts Regulator Company warrants each product to be free from defects in material and workmanship under normal usage for a period of one year from the date of original ship-
ment. In the event of such defects within the warranty period, the Company will, at its option, replace or recondition the product without charge. This shall constitute the sole and exclusive remedy for
breach of warranty, and the Company shall not be responsible for any incidental, special or consequential damages, including without limitation, lost profits or the cost of repairing or replacing other
property which is damaged if this product does not work properly, other costs resulting from labor charges, delays, vandalism, negligence, fouling caused by foreign material, damage from adverse
water conditions, chemical, or any other circumstances over which the Company has no control. This warranty shall be invalidated by any abuse, misuse, misapplication or improper installation of
the product.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE.
Any implied warranties that are imposed by law are limited in duration to one year.
Some States do not allow limitations on how long an implied warranty lasts, and some States do not allow the exclusion or limitation of incidental or consequential damages. Therefore the above
limitations may not apply to you. This Limited Warranty gives you specific legal rights, and you may have other rights that vary from State to State. You should consult applicable state laws to determine
your rights.
For valves with CPVC or PEX end connections, do not exceed the
tubing manufacturers pressure and temperature ratings. Refer to the
tubing manufacturers product specifications for that information.
WARNING
!
IS-1170C-M2 1325
EDP# 1915911
© 2014 Watts
USA:
Tel: (978) 688-1811 • Fax: (978) 794-1848 • www.watts.com
Canada:
Tel: (905) 332-4090 • Fax: (905) 332-7068 • www.watts.ca
A Watts Water Technologies Company
WARNING:
This product contains chemicals known to the
State of California to cause cancer and birth defects or
other reproductive harm.
For more information: www.watts.com/prop65
