Raypak 503-2003 - Manual (Page 40)

40
Modulating Temperature Control
This heater is equipped with a Raypak modulating
temperature control. Refer to information starting on
page 30 for information on the setting and use of this
control.
Low Water Cut-Off (Optional)
The optional low water cut-off automatically shuts
down the burner whenever water level drops below the
level of the sensing probe. A 5-second time delay pre-
vents premature lockout due to temporary conditions
such as power fluctuations or air pockets.
Fig. 39: Modulating Temperature Control
High Limit—Auto Reset (Optional)
This heater may be equipped with an optional adjust-
able auto reset high limit temperature device.
The optional adjustable auto reset high limit is located
inside the heater junction box. Adjust the setting to
approx. 20°F (10°C) above desired outlet temperature.
Flow Switch
This standard, dual-purpose control, mounted and
wired in series with the main gas valve, shuts off
heater in case of pump failure or low water flow.
Fig. 37: Adjustable High Limit (Auto Reset)
Fig. 38: Flow Switch
Fig. 40: Low Water Cut-Off