Pentair ETi 400 Guide D'installation page 10

10
Replacing Combustion Blower (Continued)
Figure 6.
Gas-train Union
20. Be sure the GAS ORIFICES are positioned vertically, not at an angle, then
reattach the gas-train to the blowers and the gas valve. Using either channel locks
or an adjustable wrench, hand tighten the unions to ensure a proper seal, see
Figure 6 and Figure 7.
21. Leak test the blower by operating it with the gas turned off, turning on the power,
and then increasing the temperature setting on the membrane pad. Use a soapy
water solution to leak test the blowers outlet flange.
Note: When checking for leaks, raise the blower's outlet pressure by
blocking the flue or vent body with your hand.
22. Open the manual gas supply valve. Leak-test the gas line with a soapy water
solution. Be sure there are no gas leaks.
23. Start the heater. Observe it for smooth ignition and regular combustion without
undue noise or pulsation.
24. Run the heater for at least 10 minutes. After at least 10 minutes of continuous
operation, insert a combustion analyzer probe into the exhaust and measure
CO2. The recommended CO2 ranges for natural gas and propane are listed in
Table 2. Preferably, the readings should be in the midrange.
Table 2. Flue Gas CO2 and O2 Ranges
Fuel
NG
Propane
25. Replace the water manifold service panel and side service panel. See Figure 1
on page 8.
Recommended CO
(Dry Basis)
7.80% – 9.2%
9.6% – 10.2%
Union
Figure 7.
2
Union
Orifice