on-off cycling heater. The valve has a remote capillary bulb immersed in a well, at the header outlet, to main- tain a constant outlet water temperature. When multiple valves are furnished, they can be staged to give greater flexibility of control. Standard factory set- ting is at position 5. Consult the dial setting tag attached to the control for your desired temperature. See Fig. 22 below.
Fig. 22: Dial Setting Tag
Fig. 24: Motorized Gas Valve Location—Model 3001
Limit Controls
High Limit
The heater is equipped with a manual reset High Limit. Push the reset button and set the limit(s) to 30°F–40°F above desired operating temperature. Maximum set- ting is 200°F; other options may be available.
Fig. 25: High Limit
Flow Switch
This dual-purpose control shuts off the heater in case of pump failure or low water condition and is strongly recommended. It is mounted and wired in series to the main gas valve.
NOTE: The flow switch is a safety device and not a control. Do not operate the heater with flows less than the minimums stated in this manual.
Fig. 23: Mechanical Modulating Valve Location—
Models 0724-1336
Fig. 26: Flow Switch