Pentair ETi 400 Guide D'installation page 7

Combustion Blower Kit Information
The ETi 400 High Efficiency Heater Burner System includes the Combustion Blower,
®
Air Orifice, Combination Gas Control Valve, Gas Orifice, DSI electrode, and Flame
holder.
Location
There are two combustion blowers in the heater. Each blower is attached to each heat
exchanger. See figure 1.
Function
The Combustion Blower draws in air and gas, and forces the air/gas mixture into the
burner. The Air Orifice, attached to the Blower inlet, meters the flow of combustion
air to the Burner. The Blower inlet is under a negative pressure, and the Blower outlet
is at a positive pressure. To check Combustion Blower operation, disconnect the
flexible plastic tubes at the Pressure Switch and connect them to a differential pres-
sure gauge. Turn the gas off and press POOL ON. When the Blower starts, check the
Table 1: Pressure Differential
Model
ETi 400
WARNING! Fire and explosion hazard. The Air Orifice is sized specifically
for the air/gas mixture required by the burner. Do not modify the Air Orifice
or replace it with an orifice of a different size. Exhaust from an improperly
sized air orifice will contain toxic levels of carbon monoxide gas and flue
gases, which can cause serious injury or death. CARBON MONOXIDE GAS
IS A DEADLY, dangerous, poisonous gas you cannot see or smell.
WARNING! Fire and explosion hazard. The Combustion Air Blower handles
a combustible air/gas mixture. When servicing this part, check all seals for
tightness to ensure the Blower is not leaking. Pentair strongly recommends
after replacing an air orifice initially and periodically test it for proper operation.
This testing can be accomplished by using a hand-held carbon monoxide
meter and/or by consulting with a gas professional.
Pressure Differential Nominal (in W.C.)
Safety Precautions
For Technincal Support, call (800) 831-7133.
ETi 400 High Efficiency Heater Combustion Blower Replacement Kit Installation Guide
2.0 in
7