Operating Instructions; To Turn Off Gas To Appliance - Pentair MT125 Installation And User Manual

OPERATING INSTRUCTIONS

1. STOP! Read the safety information on page 42.
2. Set both pool and spa thermostats to the lowest settings.
3. Turn off all electric power to the appliance. Turn OFF the Manual
Shut-Off Valve, see Figure 40.
4. This appliance does not have a pilot. It is equipped with an ignition
device which automatically lights the burner. Do not try to light the
burner by hand.
5. Remove the access door panels by unfastening the two (2) screws
located on each door, then lift up and out from the bottom of the panel
to remove. If necessary, the screws may be used as handles,
see Figure 39.
6. Toggle-Style Valve: Pull toggle toward you to turn gas off ,
see Figure 39.
7. Wait five (5) minutes to clear out any gas. If you then smell gas,
STOP! Follow "B" in the "Before Start-up" instructions (page 42).
If you don't smell gas, go to the next step.
8. Turn ON the Manual Shut-Off Valve (as shown on right).
Toggle-Style Valve: Push the toggle switch away from you to switch
the gas on.
9. Replace the Door Access Panels. All panels must be in place when
operating the heater.
10. Set 3-way valves on inlet and outlet to pool or spa, as appropriate.
11. Turn on all electric power to the HEATER.
12. Press the POOL/SPA button to toggle between POOL and SPA
mode and to display the selected pool or spa body of water actual
temperature and set point. .
13. Press the HEATER OFF (Red LED OFF), then press the UP or DOWN
button to increase or decrease the water temperature set point.
Note: The setpoint must be above the actual water temperature or
burner will not fire). See "CONTROL PANEL on page 46.
14. The blower should come on immediately, and after about 20 seconds,
the burner should fire. When operating for the first time, the burner
may
not fire on the first try because of air in the gas line. If it does not fire
at first, push the OFF switch, wait five minutes, and again press the
POOL/SPA button, then press the HEATER OFF button (Red LED on).
The burner should fire after about 20 seconds. Repeat until all of the air has cleared the gas line.
15. The burner should fire until the pool/spa temperature reaches the desired temperature set on the
thermostat. The blower will continue to run for about 45 seconds after the burner shuts off. If any of the
safety interlocks should open during burner operation, the burner shuts off immediately, but the blower
continues to run for about 45 seconds. Should overheating occur or the gas supply fail to shut off, turn off
the manual gas control valve to the appliance.
16. If the appliance will not operate, follow the instructions below
"TO TURN OFF GAS TO THE APPLIANCE", and call a service technician
or gas supplier.

TO TURN OFF GAS TO APPLIANCE

1. Press the OFF button on operating control.
2. - Switch off all electric power to the unit.
- Turn OFF the Manual Shut-Off Valve (as shown on right)
3. Remove the access door panels, see Figure 39.
4. Toggle-Style Valve: Pull toggle toward you to turn gas off, see Figure 41.
5. Replace the Access Door Panels.
460906 Rev. D 8/2020
Gas control is shown OFF.
Push toggle switch away
from you to switch ON.
MANUAL SHUT-OFF VALVE LOCATION
MASTERTEMP 125 Pool and Spa Heater Installation and User's Guide
Section 2. Operations
Water
Pressure
Switch
Figure 39.
Figure 40.
Manual
Shut-off
Valve
43
Figure 41.