Installation Guide

SPECIFICATIONS
Outlet temperature range
95 –131°F
(35–55°C)
Maximum hot supply
185°F max
(85°C)
Cold supply range
39–80°F
(4–26°C)
Temperature stability
(nominal)
± 5°F
1
(± 3°C)
Temperature differential
(between hot supply and outlet temperature)
20°F
2
(11°C)
Working pressure
30–150 psi
(2–10 bar)
Permitted inlet supply pressure variation 2:1
3
Flow rate C
v
3/8"– 1.26
1/2”, 3/4", 1”– 2.5
Flow rate, minimum
1.0 gpm
(4 L/min)
1. As tested in accordance with ASSE1017.
2. This is the minimum difference required between the valve outlet temperature and the hot supply temperature to enable
the valve to function correctly and ensure shut-off of outlet ow in the event of cold supply failure.
3. Maximum permitted variation in either supply pressure in order to control the outlet temperature to within ±5°F.
Excessive changes in supply pressures may cause changes in outlet temperature.
SERVICING AND INSPECTION
• The Webstone Thermostatic Mixing Valve is a SAFETY VALVE. Inspect the TMV at least once per year to verify it is
operating correctly. It may be necessary to check the valve more frequently in installations with poor or unknown
water quality. Outlet temperature may vary due to seasonal changes in cold water supply temperatures.
• When testing, verify the temperature at the same water outlet measured during initial setup. Allow water temperature to
stabilize before measuring. If the temperature differs more than 5°F from initial setup, refer to the troubleshooting table below.
Problem Solution
Unable or difficult to set correct
mixed water temperature
• Ensure inlet temperatures meet TMV specications
• Ensure that hot and cold supply lines have not been reversed
• Ensure strainers are not blocked
Mixed water temperature is not
stable or changes over time
• Ensure strainers are not blocked
• Ensure supply pressures are stable. Install
pressure regulating valves to correct
Full hot or full cold water flowing from MIX outlet • Verify valve temperature setting
• Ensure that hot and cold supply lines have not been reversed
• Ensure that check valves are not clogged or damaged
• Ensure inlet temperatures meet TMV specications
No flow from MIX outlet • Ensure adequate hot or cold water supply
• Ensure inlets are not blocked
Reduced or inconsistent flow rate • Ensure inlets are not blocked
• Ensure supply pressures are stable. Install
pressure regulating valves to correct
Mixed water temperature remains
same when handle is moved
• Ensure that hot and cold supply lines have not been reversed
Hot water flows into the cold water system,
or cold water flows into hot water system
• Ensure that check valves are not clogged or damaged
TMV is noisy • Ensure water supply pressures are within TMV specications.
Install pressure regulating valves to correct
• Ensure TMV is correct size for required ow
©2017 NIBCO INC., All Rights Reserved.
TMVUS-0417