Instructions / Assembly

Zone Valves
Models 555-1/2", 556-3/4", 557-1", 570-1/2", 571-3/4", 572-1", 573-1 1/4"
100-3.2A
SUPERSEDES: June 25, 1983 EFFECTIVE: March 21, 2019
Plant I.D. 001-302
WARNING: Never remove Power Head while thermostat is calling for heat. If necessary to remove Power
Head, disconnect No. 1 wire from Power Head, wait four (4) minutes, then proceed.
Instruction Sheet
Electrical
Volts 24
Amps 0.9
Temperature Range
Maximum 240°F (115°C)
Minimum 40°F (5°C)
Working Pressure
(at valve, including pump head)
125PSI (861kPa)
Maximum
differential pressure
across valve
(pump head)
555-557 150 ft. (46m)
570-573 65 ft (20m)
Service
Closed system water
or water/glycol up
to 50%
TO SERVICE
TO REASSEMBLE
Reverse above procedure pushing down on seat assembly
and hold down plate against return spring.
INSTALLATION
Valves should be installed vertically, to simplify replacement or
cleaning of the seat, if ever required at some future date. The
vertical installation permits drawing a vacuum in the system and
replacing or cleaning the seat without draining the system.
Valve may be sweat into the line without taking apart, provid-
ed, care is taken to prevent overheating. Follow these simple
instructions:
1. Use a torch with sharp, pointed ame.
2. Clean surfaces thoroughly and use a good grade of ux.
3. Use of a solder with a melting point below 600°F is recom-
mended. Do not overheat! Direct ame tip away from the
center of the valve.
4. Avoid excessive use of ux.
APPLICATION
The Taco Heat Motor Zone Valve is an electricity operated
valve used for zone control of Hydronic Heating and/or
Cooling Systems. It controls the ow of water in a room
or zone in response to the demands of the room or zone
thermostat.
RATING
1. Twist off Power Head 2. Remove the 4 screws from
hold down plate
3. Remove seat assembly
Size
Pressure Drop Characteristics
C
V
K
V
Equiv. Length of Pipe
Feet Meters
1/2" 4.2 3.6 8 2.4
3/4" 6.1 5.3 20 6.1
1" 7.0 6.1 65 19.8
1 1/4" 7.2 6.2 150 45.7