Robertshaw 720 SERIES Installation and user guide

INSTALLATION DATA
720 SERIES
HOT SURFACE IGNITION GAS VALVE
The Robertshaw® 720 series gas valves for use on hot surface ignion
systems are designed for a wide variety of applicaons. The 720 series
valves incorporate a manual valve, dual automac valves and a main
gas pressure regulator. Models for step-opening are also available.
720 valves have their pressure regulators factory pre-set at 3.5 W.C. for
natural gas. Uni-Kit models can be converted to L.P. by installing the
regulator conversion kit (included).
720 series valves feature wiring connecons, manual selector and
adjustments that are all easily accessible on top of the valve. With a
3-9/16” swing radius, the 720 series lends itself well to replacing many
O.E.M. valves. The 720 valves are mul-posion and can be mounted in
any posion (except upside down).
SPECIFICATIONS
Electrical Rangs .........................................................24 VAC, .5 amps
Pressure Regulator
Natural Gas ....................................................factory set at 3.5” W.C.
L.P. Gas..........................................................factory set at 11.0” W.C.
Ambient Temperature ......................................................-40° to 175°F
Maximum Inlet Pressure ......................................................... 1/2” PSI
REGULATION CAPACITIES
INSTALLATION INSTRUCTIONS
SIZE
MIN. MAX. MIN. MAX.
3/8” x 3/8” 15,000 175,000 15,000 437,000
1/2” x 3/8” 15,000 175,000 15,000 437,000
1/2” x 1/2” 15,000 200,000 15,000 500,000
1/2”x 3/4” 15,000 200,000 15,000 500,000
3/4” x 3/4” 15,000 200,000 15,000 500,000
NATURAL L.P.
TYPE GAS
CAUTION
THIS DEVICE SHOULD BE INSTALLED BY A QUALIFIED
TECHNICIAN WITH DUE REGARD FOR SAFETY AS IMPROPER
INSTALLATION COULD RESULT IN A HAZARDOUS CONDITION.
FOR YOUR SAFETY
IF YOU SMELL GAS: (A) turn o gas at line valve or meter, (B) open
windows, (C) do not touch electrical switches, (D) exnguish all open
ames, (E) immediately call your gas supplier from neighbors.
To avoid possible injury, re and
explosion, please read and follow
these precauons and all
instrucons on the appliance.
This bullen is intended as a
guide to qualied servicemen
installing or servicing Robertshaw
Controls. Repairs, adjustments
and servicing should be limited
to the operaons listed in this
bullen or on the appliance.
Turn o gas supply and electrical power to
equipment before servicing
PIPING
1. Check replacement valve for mulple outlets (side outlets). If it has
them, be sure all unused outlets are plugged using the sockets
provided.
2. Pipe or tubing must be clean and free of scale and dirt.
3. Make sure gas piping is pressure tested before control is connected.
High pressure can damage control causing a hazardous condion.
Do not subject control to more than 1/2 PSI, (14” W.C.) inlet
pressure.

INSTALLATION INSTRUCTIONS (CON’T)
4. If it’s not already installed, a drip leg (sediment trap) must be added
to the gas supply line to the control. (See gure below). All piping
must comply with local codes and ordinances and with Naonal
Fuel Gas Code (ANSl.1/NFPA, No. 54).
5. Using pipe thread compound suitable for gas being used, apply a
small amount on the male pipe threads. (Do not use Teon tape or
Teon compound). Leave the rst two threads clean. Never use
compound on female threads as it might be pushed into the
control body.
6. The gas valve is mul-posion and can be mounted in any posion
(except upside down) without aecng its operaon.
7. Install gas valve so gas ow conforms with the inlet and outlet of
the control.
8. DO NOT insert any object other than suitable pipe or tubing in the
inlet or outlet of this control. Internal damage may occur and result
in hazardous condion. A backup wrench should only be used on
the wrench boss provided for this purpose (see drawing), never on
body of the control, as this could distort the casng. NOTE: Do not
overghten any pipe connecons, as this could crack the valve body.
A valve with a cracked valve body will not be warraned.
PILOT TUBING
NOTE: Some hot surface applicaons use the pilot outlet, if so proceed
as directed below. If not used install pilot outlet tubing plug packaged
in the 720-079 gas valve kit then proceed to “wiring”.
1. Make sure tubing is free of burrs and dirt.
2. We strongly recommend that the pilot orice be checked and
cleaned if necessary at this me.
3. Connect pilot tubing into the control using ng provided, and
ghten for a gas-ght seal.
WIRING
DO NOT short gas valve terminals. This will damage wall thermostat
and void warranty.
Check the system for the proper transformer by comparing the VA
rangs of the transformer and the system. The system rang is
determined by mulplying the voltage draw mes the amp draw.
Normally 20VA transformers are sucient for heang only applicaons
and 40VA for heang/cooling applicaons.
NOTE: Improper transformer VA rang will cause errac system
operaon.
7200 DER MODELS
1. Connect the gas valve terminal #1 to the “valve” terminal on the
ignion control module. See wiring diagram shown below.
2. Connect the gas valve terminal #2 to the “valve” terminal on the
ignion control module. See wiring diagram shown below.
7200 IPER MODELS
3. Locate the white wire terminal adaptor (jumper) that is included
with the gas valve.
4. Connect white wire terminal adaptor to the “M” and “P” terminals
on the gas valve.
5. Determine which wire was connected to the “main valve” terminal
on the original valve. Connect this wire to the remaining terminal on
the white wire terminal adaptor.
PRESSURE REGULATOR VENT
The 720-079 has a built-in Vent Limiter. The regulator vent is taped 1/8”
tubing if vent tubing is required. CAUTION: If bleed tubing is used, do
not allow main burner or pilot ame impingement on the tubing as this
will eventually cause clogging of the tubing and improper regulator
operaon. If bleed tubing is not used the regulator vent must be
properly shielded from moisture.
LEAK TEST
Leak test with a soap soluon aer installing with main burner on. Coat
pipe and tubing joints, gasket, etc. with soap soluon. Bubbles indicate
leaks.
TO “GROUND”
ON IGN. MODULE
TO “VALVE”
ON IGN. MODULE
M
P

CAUTION
1. WARNING: If you do not follow these instrucons exactly, a re
or explosion may result with property damage, personal injury
or loss of life.
2. Smell all around the appliance area for gas. If the appliance uses
L.P. (boled) gas also be sure to smell next to the oor because
L.P. gas is heavier than air.
3. WARNING: If you smell gas, immediately shut o the manual
valve in the gas piping to the appliance. Don’t touch any
electrical switch or use the phone. Leave the building and call
your gas supplier. If he cannot be reached, call the re
department.
4. WARNING: Do not force the gas control knob on the appliance.
Use only your hand to push down and/or to turn the gas control
knob. Never use any tools. If the gas control knob will not
operate by hand, the control should be replaced by a qualied
service technician. Forced or aempted repair may result in re
or explosion.
5. WARNING: The gas control must be replaced if it has been
exposed to water.
INSTALLATION INSTRUCTIONS (CON’T)
OPERATING INSTRUCTIONS
1. Turn wall thermostat to its lowest seng. Remove burner access
panel(s).
Selector arm must only be operated by hand (see below). DO NOT
use pliers, wrenches or other tools to operate the arm. The selector
arm cannot be moved into the “o” posion without rst
depressing the lever to the “on” posion.
2. Move selector arm to the “o” posion. (See gure 1.)
3. WARNING: Wait at least 5 minutes to allow any gas in the
combuson chamber to vent. If you then smell gas in the appliance
area or near the oor, STOP and follow warning instrucons to the
le. Failure to do so may result in re or explosion.
4. Move selector arm to the “on”’ posion, (see gure 2), and set
room thermostat to desired temperature. Allow burner to cycle on
and o.
5. Leak test with a soap soluon aer installing with main burner on.
Coat pipe and tubing joints, gasket, etc. with soap soluon. Bubbles
indicate leaks.
6. Replace burner access panel.
Figure 1 Figure 2

Customer Service Telephone [phone]
Customer Service Facsimile 1.800.426.0804
[email protected]
Robertshaw®, Ranco®, Paragon® and Uni-Line® are
trademarks of Robertshaw, its subsidiaries and/or
affiliated companies. All other brands mentioned
may be the trademarks of their respective owners.
For Technical Service
Telephone [phone]
Facsimile 1.630.260.7294
[email protected]
www.uni-line.com
www.robertshaw.com
©2014 Robertshaw
09/14 –1-810 RevC
WARNING
Servicing of gas controls, appliance and systems must be
performed by qualied service personnel only.
CAUTION: If control has been exposed to water in any way, it must be
replaced. If gas valve fails to shut o, do not turn o electrical power.
Turn o gas supply allowing fan or circulang pump (if so equipped) to
connue running unl system has cooled. Replace control.
PRESSURE REGULATOR ADJUSTMENTS
Adjustment of the pressure regulator is not normally necessary since it
is preset at the factory. However, eld adjustment may be accom plished
as follows:
NOTE: Manometer aachment may be accomplished at pressure tap
plug, above control outlet, as shown in gure to the right. If using inlet
pressure tap to measure incoming pressure. See drawing on rst page.
1. Manometer or gauge aachment may be accomplished at
pres sure tap plug (D).
2. Remove regulator adjustment screw cap (top of control - A).
3. With small screwdriver, rotate adjustment screw (B) “clockwise”
to increase, or “counterclockwise” to decrease pressure to comply
with manufacturer’s specicaons.
4. Replace regulator adjustment screw cap (A).
REGULATOR CONVERSION
CAUTION: Main burner and pilot orices must be changed when
regulator is converted from one type of gas to another.
The 720 series valves can be converted from natural to L.P. by installing
the enclosed conversion kit.
1. Turn o gas and electricity to appliance.
2. Remove sloed cap (A), adjusng screw (B), and natural gas spring
not color coded - (C), from control.
3. Install new L.P. spring - color coded with a black strip.
4. Install new adjusng screw (B).
5. Aach manometer or pressure gauge at the outlet pressure tap (D).
6. Turn gas and electricity on.
7. Turn room thermostat to call for heat.
8. With burner on, adjust screw (B) to supply L.P. gas to pressure as
recommended by the appliance manufacturer.
9. If adjusng screw (B) reaches its maximum depth (booms out)
before recommended pressure seng is reached, turn screw
counterclockwise unl pressure drops slightly (approximately 0.1”
W.C.) WARNING: Do not stretch or alter spring.
10. Turn o gas and electricity to appliance.
11. Remove manometer or pressure gauge and reinstall pressure tap
outlet plug (D).
12. lnstall new red sloed cap in place of (A).
13. Turn gas and electricity on.
SERVICE INSTRUCTIONS
14. With burner operang, immediately check all ngs for leaks with
soap soluon. Bubbles indicate leaks that must be corrected.
15. Aach label to show control has been converted to L.P.
16. Set room thermostat to desired temperature.