Safety Controls (Air Flow Switches, Water Pressure Switches, Hight Limit Shut-Off Switches) - Pentair ETi 400 NA ASME Guía De Instalación Y De Usuario

Section 1: Operation Instructions
14
SAFETY CONTROLS
AIR FLOW SWITCH (AFS)
There are two air flow switches, (see Figure 2), designed as a safety device to ensure
the two combustion air blowers (fans) are operating and are monitoring the differential
(negative) pressure within the blower housing. These air pressure switches are factory
set. The switches (see page 63 #29) are connected upstream of the ignition module.
The ignition module does not operate unless the air flow switches and all safety
switches are closed.
WATER PRESSURE SWITCHES
Hazardous pressure. Do not bypass the Water Pressure Switches or render
it inoperable.
The heater has two Water Pressure switches, see Figure 3.
If the water flow is restricted, the water pressure switches
may prevent the burner from firing and cause the Service
System LED indicator to go on. Note: If the light remains
on after the filter has been serviced, have a qualified
service technician check the system.
For deck-level heater installations, the Water Pressure
switches are factory set at 3.00 psi (20.6 kPa). Note:
See Below Pool Level Installation, on page 20. If the
pressure switches are 1 ft (0.3M) below or above the pool
water level, reset the switches so that it is open when the
pump is off and closed when the pump is running. Turn
the star-wheel on the switch clockwise (
setting (heater below the pool level) and counterclockwise
( ) to lower the setting (heater above the pool
level), see Figure 4. Test each switch after resetting.
NOTICE: When the heater is mounted more than
1 ft (30 m) above or 1 ft (30 cm) below the deck level,
a pressure switch is no longer adequate. A Flow
Switch must be installed instead.
CAUTION! Heater operation with an incorrect water
pressure switch setting, may cause the heater to
operate without sufficient water flow, and may cause
severe heater damage.
HIGH LIMIT SWITCH AND
AUTOMATIC GAS SHUT-OFF
SWITCHES (AG1 AND AG2)
A High Limit Switch (HLS), is a safety device that
opens the electrical circuit and shuts off the heater based
on a water temperature set point within the HLS. The
heater contains two AGS switches and one HLS
switch. The AGS switches are located in the outlet
plumbing assembly, and the HLS switch is located on
the main Inlet/Outlet Header (see page 16).
ETi 400 High Efficiency Pool and Spa Heater Installation and User's Guide
WARNING
) to raise
Turn star wheel clockwise to raise
pressure set point if water pressure switch is
more than 1 ft (30 cm) below water level
Turn star wheel counterclockwise to lower
pressure set point if pressure switch is more
than 1 ft (30 cm) above water level
Figure 4.
Figure 2. Air Flow Switch
Water Pressure
Switch
Star Wheel
Figure 3: Water Pressure Switch
Water Pressure
Switch
Star Wheel
A reference scale is on
the back of pressure switch
Rev. C 4/2017