Pentair ETi 400 Guide D'installation page 7

Gas Connections
The heater requires a gas supply of not less than 4" (10.2 cm) wc and not
more than 12" (35.6 cm) wc. Gas supply pressures outside of this range may
result in improper burner operation. A minimum inlet pressure of 4" (10.2 cm)
wc is required to maintain input rating. The gas supply must be installed in
accordance with standard CSA B149.1 or ANSI/NFPA 58 (as applicable), and
all applicable local codes. Install a manual shut-off valve and a sediment trap
and union located outside the heater jacket. Do not use a restrictive gas cock.
The following gas pipe sizes are recommended for propane gas supply piping,
with a minimum pipe size of 3/4" (1.9 cm). Check for compliance with local
codes.
NOTICE: DO NOT use a corrugated flexible gas line to supply the heater.
It will not deliver enough gas (at nominal diameter) to supply heater.
Table 1: Gas Pipe Sizing - STAGE TWO LOW PRESSURE GAS PIPE SIZING
Maximum Equivalent Pipe Length (ft)
Natural Gas 1000 BTU/FT
0.60 Specific Gravity at 0.5 in. WC Pressure Drop
Propane Gas 2500 BTU/FT
1.50 Specific Gravity at 0.5 in. WC Pressure Drop
Input
Model (KBTU) N
™
ETi
399.0
400
Risk of fire and explosion. Improper installation, adjustment, alteration, service, or
maintenance of the Combination Gas Control Valve can lead to fire or explosion,
causing loss of life, personal injury, or property damage.
These instructions are for the use of qualified service technicians only!
Do not attempt this procedure unless you have been trained and certified in the care
and repair of gas-fired appliances!
Do not attempt this procedure if you are not confident about following instructions!
This appliance is equipped with an unconventional gas control valve that is factory
set with a manifold pressure of –0.2" wc. Installation or service must be performed by
a qualified service technician or the gas supplier. If this control valve is replaced, it
must be replaced with an identical control.
NOTICE: Before converting the heater, make the necessary gas connections to the
new gas supply, following the instructions in the ETi
User's Guide. Verify the maximum and minimum regulated gas pressures from the
gas supply. These pressures must be within the range listed on the conversion label.
3/4" 1"
P N P
20 20 60
*
INSTRUCTIONS FOR CHECKING THE GAS PRESSURE
THROUGH THE COMBINATION GAS CONTROL VALVE.
3
3
1-1/4" 1-1/2"
N P N P
90 220 200 450
400 Heater Installation and
®
ETi 400 Propane Conversion Kit Installation Guide
®
Note (*): A 3/4" (1.9 cm)
gas line can be used
for up to 2 ft (61 cm)
maximum length from the
gas valve in addition to
the sediment trap.
7