Pentair MiniMax 200 - Manuel (Page 22)

P/N • Réf. 472090 Rev. G • Rév. G 5-27-04
22
SAFETY CONTROLS
VACUUM AIR PRESSURE (FAN)
SWITCH
The air pressure switch, (see Figure 21 ), is a safety
device used to insure that the combustion air blower
(fan) is operating and has been designed to monitor
the vacuum (negative) pressure within the blower
housing. The air pressures switch is factory set and is
connected upstream of the ignition module. The
ignition module does not operate unless the air
pressure switch and all safety switches are closed.
Adjustment Knob
Typical Water Pressure Switch
Figure 22.
WATER PRESSURE SWITCH
The water pressure switch, (see Figure 22 ), closes
when there is a sufficient flow of water to the heat
exchanger to safely operate the heater. The switch has
been preset by the Factory at 1 PSIG for operation.
NOTE: See, Below Pool Level Installation
instructions on
page 7 . The switch may remain closed
with no water flow if there is more than a 3 ft. elevation
difference between the heater (heat exchanger) and
the pool water line—if this is the case, the water
pressure switch must be reset by a qualified service
technician to maintain open switch contacts with no
water flow.
NOTE
If the pool is more than one floor above or one floor
below the heater, the water pressure switch may
have to be replaced with a flow switch.
THERMAL FUSE
This is a single-use switch, mounted on combustion
chamber jacket divider (inner front panel). The fuse,
(see
Figure 23 ), is activated by excessive temperature
due to abnormal operating conditions. Upon detection
of excessive heat within the inner front panel, the fuse
will open the safety circuit causing shutdown of the
heater.
AIR PRESSURE SWITCH
Figure 21.
Air Pressure Switch
Thermal Fuse
Section IV. Operation
Figure 23.