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INSTALLATION INSTRUCTIONS (Cont’d)
5. Using pipe thread compound suitable for the gas being used, apply
a small amount on the male pipe threads. (Do not use Teflon tape
or Teflon compound.) Leave the first two threads clean. Never use
compound on female threads as it might be pushed into the control
body.
6. The gas valve is multi-positional and can be mounted in any position
(except upside down) without affecting its operation.
7. Install gas valve so gas flow 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 a hazardous condition. A backup wrench should only be used on
the wrench boss provided for this purpose (see drawing), never on
the body of the control, as this could distort the casting.
NOTE:
Do not over tighten any pipe connections,
as this could crack the
valve body. A valve with a cracked valve body will not be warrantied.
PRESSURE REGULATOR VENT
The 720-079 has a built-in Vent Limiter. The regulator vent is tapped
1/8” tubing if vent tubing is required.
CAUTION:
If bleed tubing is used,
do not allow main burner or pilot flame impingement on the tubing as
this will eventually cause clogging of the tubing and improper regula-
tor operation. If bleed tubing is not used, the regulator vent must be
properly shielded from moisture.
LEAK TEST
Leak test with a soap solution after installing with main burner on.
Coat pipe and tubing joints, gasket, etc. with soap solution. Bubbles
indicate leaks.
PILOT TUBING
1. Make sure tubing is free of burrs and dirt.
2. We strongly recommend that the pilot orifice be checked and
cleaned if necessary at this time.
3. Connect pilot tubing into the control using fitting provided, and
tighten for a gas tight seal.
WIRING
DO NOT
short gas valve terminals. This will damage wall thermostat
and void warranty.
1. Check the system for the proper transformer by comparing the VA
ratings of the transformer and the system. The system rating is
determined by multiplying the voltage draw times the amp draw.
Normally 20VA
transformers are sufficient for heating only appli cations and 40VA for
heating/cooling applications.
NOTE:
Improper transformer VA rating will cause erratic system
operation.
2. Connect the wire from the “MV” terminal on the ignition control unit
to the “M” terminal on the gas valve.
3. Connect the wire from the “PV” terminal on the ignition control unit
to the “P” terminal on the gas valve.
4. Connect the wire from the “MV/PV” terminal on the ignition control
unit to the ”C” terminal on the gas valve.
TYPICAL ROBERTSHAW INTERMITTENT PILOT APPLICATION
INSTALLATION INSTRUCTIONS – INTERMITTENT PILOT