Pre-Installation
1. Visually inspect THERM-X-TROL
®
for any damage. If
damage exists return product for replacement.
2. Adjust pre-charge to equal incoming pressure.
If increasing the pre-charge
pressure above 55 psig, the
following steps must be followed:
a. Tank must be connected to the system with isolation
valve open.
b. System must be pressurized to 55-60 psi or slightly
higher than the pre-charge setting of the tank.
c. Isolation valve then needs to be closed.
d. The pre-charge pressure of the tank can now
be increased to the recommended high pressure
setting.
e. Bring system up to pressure, and then open the
isolation valve to the tank.
Failure to follow these instructions could result in
damage to the bladder or diaphragm and void all
warranties.
3. Replace and tighten plastic cap on air fitting.
For commercial water heater installations, contact
AMTROL for information.
Installation
1. Install the THERM-X-TROL
®
on the city supply line to
the water heater at a point between the water heater
and backflow preventer, check valve or pressure
reducing valve (see Figure 1).
2. Once the THERM-X-TROL
®
is installed, check the city
supply line for any leakage. Make repairs if necessary.
3. Before the initial firing of the water heater, open
any hot water fixture and draw water until all air is
removed from the system. Turn the water heater
temperature control to desired ending temperature
level, (see water heater instructions).
4. To relieve initial thermal expansion, slightly open
a hot water faucet. Continue until water heater
aquastat temperature is satisfied. Once heater is at
its operating range, no further bleeding of expanded
water is required.
5.
The system water heater and THERM-X-TROL
®
will now be operational. The THERM-X-TROL
®
will
control temperature and pressure increases caused
by thermal expansion to a level well below the water
heater relief valve setting.
Maintenance
1. A professional plumber should check the complete
heating system, including the THERM-X-TROL
®
,
yearly and more frequently as the system ages.
Operation
1. The THERM-X-TROL
®
is installed in the supply
line between the backflow preventer and the water
heater. Its sealed-in air pre-charge prevents water
from entering it until the system pressure exceeds the
pre-charge pressure.
2.
As the water temperature rises, expanded water
enters the THERM-X-TROL
®
’s non-corrosive water
reservoir. The pre-charged air chamber absorbs the
pressure increase, keeping system pressures below
the relief valve setting.
3.
As hot water is used, the pressure in the air
chamber forces water back into the system until the
THERM-X-TROL
®
is empty. At this point, the pressure
in the air chamber once again equals the supply
pressure.
4. Water treatment is not to exceed 200° F or fall below
35° F.
NOTE:
Models are listed (ST-5-C thru ST-210V-C)
under ANSI/NSF Std 61 and City of Los Angeles
.
City Supply
City Supply
B A CK FL O W PREVENTE R
CHECK V A L VE OR PRESSUR E
REDUCING V A L V E
W ate r
Heater
THERM-X-TROL
®
S T -5C, S T -12 C
Relief
V alv e
Hot W ate r
Hot Water
THERM-X-TROL
®
ST-20V-C
through ST-210V-C
Water
Heater
Figure 1.