Basic Operation - General Description - Pentair Pool Products MiniMax 250 Operating & Installation Manual

Basic Operation
GENERAL DESCRIPTION
The MiniMax NT Low NOx Pool and Spa Heater is a fan-assisted induced draft appliance. The MiniMax
NT Low NOx is available in 200,000, 250,000, 300,000 and 400,000 btu/hr. capacities and are certified for
both indoor and outdoor installations. The MiniMax NT Low NOx version natural gas pool heater must be
used for installations in the South Coast Air Quality Management District (SCAQMD)—these heaters are
certified to comply with SCAQMD Rule 1146.2 and also meet Ventura Co. APCD Rule 74.11.1.
The MiniMax NT Low NOx is designed to operate both in stackless outdoor installations and in indoor
stack vent installations—the indoor installation may be made using Kit 460506 or 460507; see pages 6 and
17, vertical vent pipe or with a horizontal vent pipe and a Listed side-wall vent.
BASIC SYSTEM OPERATION
TO OPERATE HEATER
1. Start pump, make sure the pump is running and is primed, to close water pressure switch and
supply power to heater.
2. Set thermostat to lowest setting by using up/down arrow keys. See page 24.
3. Push the off key on the Pentair temperature controller 7800 (the amber "off " led will illuminate).
See page 24.
4. Open the access doors.
5. Push in the gas control knob slightly and turn the knob clockwise to "OFF". See page 5 Natural Gas
Instructions.
6. Wait (5) minutes to clear out any gas. If you then smell gas STOP. Follow the safety information
(stated earlier in the lighting instructions section). If you don't smell gas, go to the next step. See
page 5 Natural Gas Instructions.
7. Turn the knob on the gas control counter clockwise to the "ON" position. See page 5 Natural Gas
Instructions.
8. Replace the doors.
9. Push either the "Pool" or "Spa" key to start the heater. NOTE: "Pool" key is Factory set at 78° and
"Spa" key is set at 104°.
10. Set the thermostat if needed by using the up/down arrows to set the desired temperature.
a. Fan motor starts, which closes draft proving switch.
b. Ignition module is energized after fan prepurge cycle is completed approximately 2 minutes.
c. Check for powering up the (glow coil) hot-surface ignitor by viewing through the sight glass.
11. The ignitor will warm up and then gas valve opens to ignite the main burners.
12. Heater will operate until desired temperature is reached.
P/N 471593
20
Rev. C 11-1-01