Gas Pressure Setting Verification - Pentair ETi 400 Guide D'installation

8
Gas Pressure Setting Verification
After completing the Servicing Procedure (see page 7) proceed with the following
steps to verify the gas supply pressure.
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.
Fire and explosion hazard. The Combustion Blower handles a combustible
air/gas mixture. When servicing this part, check all seals for tightness to
ensure that the Blower is not leaking.
1. Turn off the electrical supply to the heater.
2. Turn off the pump and shut off the manual gas supply valve to the heater.
3. Use a 3/16" hex key to remove the plug from the PRESSURE TAP port on the
outlet side of the Combination Gas Control Valve.
4. Install a 1/8" NPT barbed fitting into the 'PRESSURE TAP' port on the outlet
side of the gas valve. Use a flexible tube to connect it to the low side of a
differential pressure gauge or a slope gauge. This gauge will measure low
(outlet) pressure, which requires a high degree of resolution.
5. Turn on the manual gas shutoff valve.
6. Before operating the heater, leak-test all of the gas connections with soapy
water.
WARNING! Risk of fire or explosion. Never test for gas leaks with an
open flame.
7. Turn on electricity to heater and start the pump.
8. Turn on the heater.
NOTICE: If you are using a slope gauge, close the shutoff valve of the
gauge to avoid pulling the liquid out of the gauge when the blower starts.
9. After the burner lights, verify that the supply pressure is within the range 4" to
12" wc. If the supply pressure drops below this range when the burner ignites,
the gas line capacity may be inadequate, and should be increased.
10. With the burner still on, disconnect the plastic hose between the gas valve and
"VENT" tap and the blower mixer inlet. The pressure gauge should then read
. (Since the pressure tap is connected to the low side of the gauge,
.2" ±.1" wc
the pressure is actually negative.) If the pressure is outside the range listed,
call the factory at
ETi 400 Hight Efficiency Heater Gas Control Valve Replacement Kit Installation Guide
Do not try to adjust the pressure yourself.
1-800-831-7133.