Below Pool Level Installation; Flow Switch - Pentair MASTERTEMP 175K BTU/HR Guide D'installation Et D'utilisation

Section 3. Installation Instructions
VALVES
When any equipment is located below the surface of the pool or spa, valves should be placed in the circulation piping
system to isolate the equipment from the pool or spa. Check valves are recommended to prevent back-siphoning. Back-
siphoning is most likely to occur when the pump stops, creating a pressure-suction differential. Do NOT sanitize the pool
by putting chlorine tablets or sticks into the skimmer(s). When the pump is off, this will cause a high concentration of
chlorine to enter the heater, which could cause corrosion damage to the heat exchanger.
Exercise care when installing chemical feeders so as to not allow back siphoning of chemical into the heater, filters
or pump. When chemical feeders are installed in the circulation of the piping system, make sure the feeder outlet line
is down stream of the heater, and is equipped with a positive seal noncorrosive "Check Valve", (P/N R172288),
between the feeder and heater.
MANUAL BY-PASS
Where the water flow rate exceeds the maximum 120 GPM, a manual
bypass should be installed and adjusted. After installing the valve, adjust
the valve to bring the flow rate within the acceptable range. Then remove
the valve handle or lock it in place to avoid tampering. See
M d o l e M . n i G ( P M ( ) P L ) M
1 7 5 2 0 7 ( ) 6
2 0 0 2 0 7 ( ) 6
2 5 0 2 5 9 ( ) 5
3 0 0 3 0 1 ( 1 ) 4
4 0 0 4 0 1 ( 5 ) 2
* D o n t o x e e c d e t e h m x a m i u m
a r e t o f t r e h c n o e n i t c g n
* Pumps 2 HP or larger can produce water pressure
flow in excess of 120 GPM. For these pumps, a
BY-PASS VALVE is recommended.
See page 46 for Pressure Relief Valve Installations.

BELOW POOL LEVEL INSTALLATION

If the heater is below water level, the pressure switch must be adjusted. This adjustment must be done by a qualified
service technician. See following CAUTION before installation.
The water pressure switch is set in the factory at 3.00 PSI (± 0.75 PSI). This setting is for a heater installed at pool level.
If the heater is to be installed more than 1' above or below, the water pressure switch must be adjusted by a qualified
service technician. See page 35, Figure 29.
If the heater is installed more than 5' above the pool or more than 4' below the pool level, you will be beyond the limits
of the pressure switch and a flow switch must be installed. Locate and install the flow switch externally on the outlet
piping from the heater, as close as possible to the heater. Connect the flow switch wires in place of the water
pressure switch wires.
Rev. N 10/2018
Table 1.
M a . x G ( P M ( ) P L M * )
1 2 0 4 ( 5 ) 4
1 2 0 4 ( 5 ) 4
1 2 0 4 ( 5 ) 4
1 2 0 4 ( 5 ) 4
1 2 0 4 ( 5 ) 4
e r o c m m e d n d e o l f w
p p i n i . g
BELOW OR ABOVE POOL INSTALLATION
CAUTION
Figure 4.
CAUTION

FLOW SWITCH

MASTERTEMP Pool and Spa Heater Installation and User's Guide
Figure 4.
Warm water out
1. Set Manual By-Pass Valve.
2. Remove Handle.
Outlet to pool
13
Cool water
Inlet to heater