Amtrol ST-5C THROUGH ST-201VC Please Read the Following Instructions Carefully, Installation

PLEASE READ THE FOLLOWING INSTRUCTIONS CAREFULLY

IMPORTANT GENERAL SAFETY INFORMATION -

ADDITIONAL SPECIFIC SAFETY ALERTS APPEAR IN THE FOLLOWING INSTRUCTIONS.

FAILURE TO PROPERLY SEAL WILL RESULT IN

LOSS OF PRECHARGE CAUSING PRODUCT TO FAIL.

Installation

THIS PRODUCT MUST BE INSTALLED BY A

QUALIFIED PROFESSIONAL.

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

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-5C through ST-210VC) under ASME Section VIII, Division I.

Warranty

ST-5C through ST-210VC Models: One (1) Year Limited Warranty

Visit www.amtrol.com for complete warranty details.

Figure 1

to the bladder or diaphragm and void all warranties.

3. Replace and tighten plastic cap on air fitting.
4.	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).
5.	Once the THERM-X-TROL is installed, check the city supply
	line for any leakage. Make repairs if necessary.
6.	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).
7.	To relieve initial thermal expansion, slightly open a hot water

BFP, Check or PRV

CWS

THERM-X-TROL

Expansion Tank

Water

Heater

Hot Water

T & P

Valve

faucet. Continue until water heater aquastat temperature is

satisfied. Once heater is at its operating range, no further

bleeding of expanded water is required.

8. 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.

BFP, Check or PRV

CWS

THERM-X-TROL

Expansion Tank

Water

Heater

Hot Water

T & P

Valve

LOW-LEAD

1400 Division Road, West Warwick, RI 02893 USA

T:800.426.8765 F: 800.293.1519 www.amtrol.com

© 2014 AMTROL Inc. Part #: 9017-091 (01/14)