
HYDROGUARD
acuum Relief Valve
Temperature Gauge
Cold
Cold
LM490, LFLM490,
LM490-10, LFLM490-10
8" - 10"
Tempered
Hot
Hot to Appliances
T&P
Relief Valve
H
C
M
Cold
ASSE 1017 Series LM490, LFLM490, LM490-10 and LFLM490-10
Installation Instructions
NOTE: Installation should be in accordance with accepted plumbing practices. Flush all pipes thoroughly before
installation. Installation and field adjustment are the
responsibility of the installer.
Installation Instructions n
1. Close both hot and cold water shutoff valves upstream of
the tempering valve.
2. Bleed pressure from the system.
3. Route copper tubing or piping to fit valve dimensions.
4. For valves with Quick-Connect tailpieces refer to "QuickConnect Installation" instructions.
5. Remove tailpieces from the valve and make sure union
nuts are over the tubing/piping before connecting to the
tailpiece.
NOTE: If soldering, remove unions and gaskets from valve
body prior to soldering to prevent damage to valve from
excessive heat.
6. Flush piping again, install valve using filter gasket on hot
and cold water inlets and fiber gasket on mixed water
outlet.
7. Turn on the cold and hot water. If any leak are observed,
tighten connections as necessary to stop leak before proceeding.
IS-P-LM490-LM490-10
®
Thermostatic Tempering Valves
LFLM490-1
Advanced Thermal
Activation
Quick-Connect Installation n
TO CONNECT
1
1
/2 in. (38.1mm)
1
/2 in.Pipe (12.7mm)
3
/4 in. (44.45mm)
1
3
/4 in.Pipe (19.05mm)
7
1
/8 in. (47.63mm)
LM490-5
IMPORTANT:
To prolong the life of the series LM490, LFLM490, LM490-10
or LFLM490-10 valves, it is recommended that the hot water
inlet to the valve should be 8-10”(200-305 mm) below the hot
water inlets.
Figure 1. Domestic Hot Water Application
1 in.Pipe (25.4mm)
1. Mark pipe as shown.
This is pipe insertion depth.
PEX tubing only
Tail Piece
3. If using PEX tubing, insert pipe stiffener (provided) into end of pipe.
Pipe Stiffener
TO DISCONNECT
1. Remove collet clip.
2. Clean pipe end.
Collet clip
Mark
4. Push tubing into tailpiece up to mark.
5. Insert collet clip.
Collet depressed
2. Depress collet.
3. Pull tubing from tailpiece .

T u rn
Hotter
Hex Wrench
Colder
Unscrew, Lift Cap
to Adjust
Temperature Adjustment
Figure 2.
To Adjust Temperature (Figure 2) n
LM490 and LFLM490 is factory pre-set to 120°F (49°C) and
LM490-10 and LFLM490-10 is factory set to 90°F (31°C) outlet
temperatures under the following conditions:
Cold inlet: 60° - 70°F (16 - 21°C)
Hot inlet: 140° - 145°F (60 - 63°C)
Supply Pressures: 45psi (310 kPa)
1. Let the water flow for at least two minutes to allow
supply temperature to stabilize.
2. Place a thermometer in the outlet water stream.
3. Loosen handle screw with hex wrench.
4. Handle must be lifted 1/4" to adjust temperature. Rotate
handle clockwise to decrease temperature and counterclockwise to increase the temperature.
5. Lower handle and tighten screw.
6. Check for outlet temperature.
NOTE: Pressure differential between hot & cold water
supplies must be less then 25%.
Caution: Need Periodic Inspection n
This valve requires periodic inspection and verification
of outlet temperature by a licensed contractor. Corrosive
water conditions, inlet temperatures over 200°F (93°C), unauthorized adjustments or repair could render the valve ineffective for service intended. Regular cleaning and checking
of thermostat assembly helps to assure maximum life and
proper product function. Frequency of cleaning depends upon
local water conditions.
Troubleshooting n
Fluctuating or erratic hot water temperature at fixture:
Unbalanced Pressure. Install balancing or throttling valve at
the hot and cold water supplies and adjust accordingly for demand.
Hot water backing up into cold water line:
Hot water pressure is higher than cold water pressure.
Examine check valves for dirt & debris, clean as necessary.
Cannot adjust water temperature to desire temperature:
Install balancing or throttling valve at the hot and cold water
supplies and adjust accordingly for demand.
High pressure drop through the tempering valve:
Valve Undersized. Install larger thermostatic tempering valve.
Insufficient hot water during peak demand:
Check flow requirement during peak demand period. Use larger
thermostatic tempering valve.
Repair Kit n
Model Part # Description
LFLM490 and LM490 490-090 Plunger/Motor Assembly
LFLM490-10 and LM490-10 490-190 Plunger/Motor Assembly
WARNING: 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:
Powers Hot Water Temperature Control Valve Series LM490,
LFLM490, LM490-10 & LFLM490-10 are designed to be installed
at or near the boiler or water heater. They cannot be used by
themselves for tempering water temperatures at fixtures where
ASSE Standard 1016 or ASSE Standard 1070 listed devices are
required. To comply with ASSE Standard 1016 or ASSE Standard
1070, listed devices such as Powers Series e480, LFe480, LM495
or LFLM495 should be used at fixtures to prevent possible injury.
Powers Hot Water Temperature Control Valve Series LM490,
LFLM490, LM490-10 or LFLM490-10 are not designed to compen sate for system pressure fluctuations. Such use may result in
severe bodily injury (i.e., scalding or chilling) and/or death.
When installing the Series LM490 or LM490-10, valves in radiant
heat applications, the components of the radiant heat system
must be of materials with a construction capable of withstanding
the high limit output temperatures of the heating boiler. If you
are uncertain as to the product’s adaptability for your application,
please consult an authorized representative before installing or
using the product.
ATTENTION INSTALLER:
After installation, please leave this Instruction Sheet
for occupant’s information.
IMPORTANT: Inquire with governing authorities for
local installation requirements.
A Watts Water Technologies Company
IS-P-LM490-LM490-10 1004 EDP# 6511207 © 2010 Powers
USA: Phone: 1.800.669.5430 • Fax 1.847. 229. 0526 • www.powerscontrols.com
Canada: Phone: 1.888.208.8927 • Fax 1.888 . 479. 2887 • www.powerscontrols.ca