Pentair MiniMax 250 - Manual (Page 29)

Rev. C 11-1-01 P/N 471593
29
3. After normal firing of the heater (main burners) the heater will continue to operate until the
temperature setpoint is reached (thermostat satisfied). As the pool/spa loses heat the heater will refire
and continue to operate cycling automatically to maintain the selected temperature setpoint for either
the pool or spa. If at anytime during the firing of the heater an unsafe condition is detected the
heater will stop firing and an automatic safe shutdown sequence will begin. Investigate and have
corrected the cause of the abnormal firing termination before placing heater back in operation.
Please Note: During the firing of the heater, you decide to change to the pool or spa selection by
depressing the selector key for “POOL” or “SPA”, the heater will first acknowledge the new selection by
flashing the new selection’s corresponding selection LED “POOL” or “SPA”, however, the heater will first
complete a safe shutdown sequence before automatically switching to the new selected setting and safely
initiating a new firing sequence using the the new temperature setpoint. During this automatic crossover
sequence the keyboard on the Pentair Temperature Controller 7800 will not accept any further keying until
the cycle completes—the exception is you may still stop the heater with the “OFF” key.
Troubleshooting—Normal Operation of Heater
Illustration of Pentair Temperature Controller 7800 with all fault icons displayed for clarity.
TFUSE AUX FAN PRESS H-LMT IGN
POWER
SERVICE
SYSTEM
HEAT
OFF SPA POOL
TEMP
TEMP
CURRENT TEMP SET TEMP/TIME
NORMAL
SET
MODE
FAULT CONDITION LCD ICONS
POOL OR SPA
(DISPLAY ALTERNATELY
ON LCD TO SHOW ACTIVE SELECTION)
PROGRAM STEP
Figure 24.