Pentair ETi 400 - Heater Operating Instructions; Operating Steps; Turning Off Gas Supply

ETi 400 Heater Fuel Gas Conversion Kit Installation Guide
ETi 400 Heater Fuel Gas Conversion Kit Installation Guide
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Sequence of Operation
An electronic temperature sensing thermistor in the manifold adapter inlet controls the
heater operation. When the inlet water temperature drops below the temperature set
on the operator control panel, the control board supplies power to the combustion air
blowers through a series of safety interlocks. The heater interlocks consist of;
• the two water pressure switches (PS), which senses that the pump is
running,
• the high limit switch (HLS), which opens if the heat exchanger outlet
temperature goes above 135° F (57° C), and
• the two air flow switches (AFS), sense the pressure drop across the
air metering orifices.
• the two thermal fuses (TF) open if the flue gas temperature reaches
187° F (86° C).
• the automatic gas shut-off (AG1, AG2) switches, which open if the
heat exchanger outlet temperature goes above
150° F (66° C).
• the float switch (FS) which opens if the condensate overflows at
the float switch due to blockage in the condensate drain hose or
neutralizer cartridge.
• the stack flue sensors (SF1, SF1), which shut down the heater if the
flue gas temperature reaches 170° F (77° C).
The air flow switches (AFS) sense the pressure differential between both of the
air metering orifices. As soon as there is sufficient air flow, the AFS closes, com-
pleting the circuit to the Fan Control board. The gas ignition control then opens
the gas valve and the fuel mixture is ignited by the Direct Spark Ignition (DSI). On
a call for heat, the blowers are energized for 15 seconds, the gas valve opens si-
multaneously as the direct spark igniters are energized, then ignition occurs. The
heater is equipped with a digital operating control that enables the user to pre-set
the desired pool and spa water temperatures. The control enables the user to
select between pool and spa heating, and features a digital display that indicates
the water temperature.
Specifications
Parts List for Propane Conversion Kit P/N 476072
Description Qty. P/N
Direct Spark Igniters 2 476081
Air Orifice 2 476064
Gas Orifice (NL) 2 476075
O-Ring 2 U9-370
Installation Guide 1 476079
Propane Conversion Label 1 476078
Inlet Pressure:
Min./Max: 4” / 12” WC
Manifold Pressure:
Reference to Blower inlet tap: -0.2” WC
Required Gas Input (BTU/Hr): 399.990 BTU/Hr
Model: ETi
®
400 Heater