Gas Connections; Gas Line/Installation; Pipe Sizing Chart/Gas Pressure Requirements - Pentair MiniMax Plus Service Manual

Gas Requirements
Gas Line Installations
Before installing the gas line, be sure to check which
fuel the heater has been designed to burn. This is
important because different types of fuel require
different pipe sizes. The rating plate on the heater will
indicate which fuel the heater is designed to burn. The
chart on this page shows which size pipe is required for
the distance from the gas meter/propane tank to the
heater.
When sizing gas lines, calculate three (3) additional
feet of straight pipe for every 90 degree elbow used.
When installing the gas line, avoid getting dirt, grease or
other foreign material in the pipe as this may cause
damage to the gas valve, which may result in heater
failure.
The gas meter should be sized to assure that it will
supply enough gas to the heater and any other
appliances that may be used on the same meter.
The gas line from the meter will usually be of a larger
size than the gas valve supplied with the heater. To
assure as little restriction as possible, the connecting
fittings at the meter should be the same size as the main
gas line and the main gas line should be reduced as
close to the heater as possible.
CAUTION
The heater and any other gas appliances must be
disconnected from the gas supply piping system
during any pressure testing on that system.
The heater and its gas connection must be leak tested
before placing the heater in operation. Do not use
flame to test the gas line. Use soapy water or
another nonflammable method.
WARNING
Do not install the gas line union inside the heater
cabinet. This will void your warranty.
P/N 38033
NOTE
Pipe Sized For Length Of Run In Equivalent Feet
1 2 / i . n 3 4 / i . n
N t a L P N t a L
M o d l e
1 ' 0 4 ' 0 5 ' 0 1 5
1 5 0
- 2 ' 0 3 ' 0 8
2 0 0
- 1 ' 0 2 ' 0 5
2 5 0
- - 1 ' 0 3
3 0 0
- - 1 ' 0 2
3 5 0
- - - 1
4 0 0
Testing Gas Pressure
1. Push the power switch to "OFF".
2. Turn the gas valve knob to "OFF".
3. Remove the pressure tap plug on the burner side of
the gas valve.
4. Attach the Manometer.
5. Turn the gas valve knob to "ON".
6. Fire the heater and read the Manometer.
Gas Pressure Requirements*
Maximum inlet gas pressure
Minimum inlet gas pressure
Normal manifold pressure
** 6 WC for 400 model
*All Readings are taken with the heater firing. Any adjustments
made with heater off will give incorrect readings.
1 0
1 i . n 1 ¼ i . n 1
P N t a L P N t a L P N t a
' 0 1 5 ' 0 6 0 ' 0 - - -
' 0 1 2 ' 5 2 5 ' 0 4 5 ' 0 6 0 ' 0 -
' 0 7 ' 0 1 5 ' 0 2 5 ' 0 5 0 ' 0 6 0 ' 0
' 0 5 ' 0 1 0 ' 0 2 0 ' 0 3 5 ' 0 4 0 ' 0
' 0 3 ' 0 7 ' 0 1 2 ' 5 2 5 ' 0 2 5 ' 0
' 0 2 ' 0 6 ' 0 1 0 ' 0 1 5 ' 0 2 0 ' 0
Propane
Natural
10 in. WC 14 in. WC
**5 in. WC 12 in. WC
4 in. WC 11 in. WC
Rev. C 12-1-00
½ i . n
L P
-
-
-
6 0 ' 0
5 0 ' 0
4 5 ' 0