Amtrol FT-109 THROUGH FT-111 Leaflet

FILL-TROL

®

 is a combination of an EXTROL

®

 expansion tank and 

a specially designed automatic pressure reducing valve. Together, 

they manage water expansion to provide satisfactory heating system 

performance.
The EXTROL  is pre-charged at the factory to 12 PSIG and is ready 

to  install in most residential and light commercial systems without 

adjustment.  The valve is designed to fill the system with water and 

automatically shut off the flow when it reaches the precharge pressure 

in the tank. It will also restore the system to 12 PSIG if the pressure 

drops below that point. The precharge may be changed to set the 

desired fill pressure.

1  Visually inspect for any damage. Ensure expansion tank is sized 

properly for application (Figure 1).

2.  Remove plastic cap from air valve.
3.  With tank empty of water, adjust air precharge to desired system fill 

pressure. Unit is shipped at 12 PSIG.

4.  Replace and tighten plastic cap on air valve.

1. Drain the boiler system or isolate the area where the unit will  

be installed.

2.  Install the unit on the supply side of the boiler, on the suction-side of 

the heating circulator(s) (Figure 2).

Mount tank vertically only. Ensure the piping 

can support the entire weight of the tank when 

full of water.

Do not install on a dead-end pipe or wherever 

air can collect; causing internal corrosion and 

possible leakage.

3.  Make connection to system with 1/2" pipe nipple from tapping marked 

SYSTEM.

4. Connect cold water supply to 1/2" compression fitting connection at 

SUPPLY.

5.  Pressurize the system and check for leaks. Repair as necessary.
6.  Restart the boiler system and check for relief valve discharge. If the 

relief valve drips, the tank may be improperly charged or undersized.

7. The unit is now operational and will absorb expanded water during 

boiler operation.

To remove screen in Fill-Trol valve for cleaning, shut off main water 

supply to heating system and remove compression nut. 
A professional plumber should check the complete system, 

including the expansion tank, yearly and more frequently as the 

system ages. Checking the precharge allows a small amount of 

air to escape and can result in an insufficient air charge. Always 

check the precharge while the tank is isolated and empty of water. 

Be sure to maintain the proper precharge whenever the tank 

 

is inspected.

Water enters the Fill-Trol valve through the 1/2" compression fitting 

connection, passes through the removable strainer and pushes open 

the spring-loaded check valve. It then flows through the automatic shut-

off valve which is held in the open position by the diaphragm pushing 

against the pressure plate. This raises the fill-gate stem and compresses 

the automatic shut-off valve spring allowing water to flow into the heating 

system. It is the charge pressure in the tank that forces the diaphragm 

into position.
As the system reaches the fill pressure, the diaphragm   moves, allowing 

the automatic shut-off valve to close.
When the system falls below the fill pressure, the diaphragm again 

pushes open the automatic shut-off valve, allowing water to flow into the 

system and restore system pressure.
The Fill-Trol is shipped with a factory precharge of 12 PSIG which 

automatically sets the minimum fill pressure to 12 PSIG. Other minimum 

fill pressures my be used by increasing or decreasing the air charge in the 

tank. Carefully follow the instructions for changing the air charge.

FT Models: Five (5) Year Limited Warranty 
Visit www.amtrol.com for complete warranty details.

Boiler

Net Output

in 1000’S

of BTU/Hr.

Type of Radiation

Finned Tube

Baseboard or 

Radiant Panel

Convectors

or Unit

Heaters

Radiators

Cast Iron

Baseboard

Cast Iron

25

FT-109

FT-109

FT-109

FT-109

50

FT-109

FT-109

FT-110

FT-110

75

FT-110

FT-110

FT-110

FT-111

100

FT-110

FT-110

FT-111

FT-111

125

FT-110

FT-111

FT-111

NA

150

FT-110

FT-111

NA

NA

175

FT-111

FT-111

NA

NA

200

FT-111

FT-111

NA

NA

250

FT-111

NA

NA

NA

© 2014 AMTROL Inc. 

Part #: 9015-026 (06/14)

1400 Division Road, West Warwick, RI  USA 02893  

T: 800.426.8765    F: 800.293.1519

Spring-Loaded 

Check Valve

Automatic Shut-Off

Valve Spring

Pipe Nipple

Expansion

Bypass

Automatic

Shut-Off Valve

Pressure Plate

Removable

Strainer

Cold Water

Supply

Fill Gate

Stem

O-Ring Seal

1/2˝ Compression

Fitting Connection

System Pressure

Above Diaphragm

Diaphragm