Amtrol 600 LBC User Manual

EXPLOSION HAZARD. Failure to follow 

instructions in the accompanying product manual 

can cause rupture or explosion, possibly causing serious or fatal injury, 

leaking or flooding and/or property damage.

This Product, like most Products under pressure, 

may over time corrode, weaken and burst or 

explode, causing serious or fatal injury, leaking or flooding and/or 

property damage. To minimize risk, a licensed professional must install 

and periodically inspect and service the Product. A drip pan connected 

to an adequate drain must be installed if leaking or flooding could cause 

property damage. Do not locate in an area where leaking could cause 

property damage to the area adjacent to the appliance or to lower floors 

of the structure.
The AMTROL expansion tank may be placed in any convenient position 

within the mechanical room (or building).  If multiple tanks are installed, 

they should all be on the same level. 

Unlike a conventional tank, the EXTROL sealed air cushion does not 

require replenishment so DO NOT connect to an air separator or other 

air collection device. 

As with any expansion tank, it is recommended that the EXTROL be 

connected to the suction side of the pump. This will prevent the pump 

head from becoming subtractive which may result in entry of air and 

vapor formation at high points in the system. 

By connecting the EXTROL on the boiler return, displacement of coolest 

system water into tank is ensured reducing energy waste. 

Low pressure drop components such as air separators and boilers may 

be placed between point of connection and pump suction if desired. 

System design will dictate the feasibility of this.

Natural convection losses and the entry of air into tanks are eliminated by 

connection to the side or underside of main pipe. The piping should be pitched 

up and away from the EXTROL to eliminate any potential air traps.

1.  Note location of system connection, air charge valve and drain 

connection on tank.

2.  Remove the plug or pipe cap from the system connection.

3.  Remove the 1 1/2” NPT plug covering the air charge valve.

4.  Before making any connection to the tank, check the tank and air 

charge (use an accurate pressure gauge). The air pressure must be 

equal to the minimum system pressure at the tank location.

IMPORTANT: If increasing pre-charge pressure above 

55 psig the following steps must be followed:

  a. Tank must be connected to the system with the isolation valve 

open.

  b. System must be pressurized to 13-14 psig, slightly above 

factory setting.

  c. Isolation valve needs to be shut.

  d. Pre-charge pressure of tank can now be increased to match 

system fill pressure.

  e. Open isolation valve and start up system.

 

5. After making sure the air charge is correct, replace the valve cap and 

the 1 1/2” plug over the air valve.

6. The EXTROL may now be piped to the system (use the suggested 

EXTROL piping diagrams on the next page).

7. Using the table below, select appropriate pipe size. Connection to 

each EXTROL must have a lock shield gate valve and union to allow 

isolation and removal if required. Make up and fill valves, whether 

manual or automatic, should be tied into the connecting line. This will 

ensure that pump operation will not affect valve operation.

Maximum Operating Pressure: As stamped on nameplate

Maximum Operating Temperature: 240 °F

Minimum Operating Temperature: 35°F (non-glycol application)

If unit is being installed in a glycol system where minimum temperatures 

fall below 35°F, contact the AMTROL technical service department at  

(401) 535-1216.

1. Check the expansion tank pre-charge before the system is filled with 

water. The charge is 12 psig unless noted otherwise on the tank label. 

Check to make sure this is the correct pre-charge pressure specified 

for the system.

2. If the tank pre-charge pressure needs to be changed on a dry system 

follow the following procedure:

  a. Check the expansion tank air pressures at the pre-charge 

connection with an accurate tire type pressure gauge. The 

pre-charge connection is the same kind of connection found on 

automobile tires.

  b.  If the pressure is low, charge the tank with nitrogen gas or with 

oil free compressed air. Check the pressure frequently during this 

process as you would when filling a tire with air.

DANGER: Excessive pressure can cause tank to 

explode. Exercise care when filling a tank with air so 

the pressure does not exceed that required or does 

not exceed the working pressure of the tank as stamped on the 

nameplate. Failure to follow these instructions will result in 

serious personal injury or death and property damage.

3. If, after the system has been filled with water and operating, it is found 

that the expansion tank pre-charge must be changed use the following 

procedure:

  a.  Turn off the heat source and allow the system water to cool to 

ambient temperature.

IMPORTANT: Expansion tank cannot be properly air 

charged other than at ambient temperature.

  b.  Close the lock-shield valve in the tank-to-system piping.

  c.  Open the drain valve to empty the water from the tank.

  d.  Check the tank air pressure at the pre-charge connection with an 

accurate tire type air gauge. 

  e.  Refer to 2b above.

  f.  Close the drain valve, open the lock-shield valve and turn on the 

heat source.

  g.  Relock the lock-shield valve.

 

Firing Rate  

Length of Pipe Connecting

 

of Boiler 

Tank to System:

 

MBTU/H 

Below 11' 

11' – 30' 

31' – 100'

 2,000 

1

/

2

" 

3

/

4

" 1"

 4,000 

3

/

4

"  1" 1

1

/

4

"

 8,000 

1" 

1

1

/

4

" 1

1

/

2

"

 12,000 

1

1

/

4

" 1 

1

/

2

" 2"

 16,000 

1

1

/

4

"  2" 2

1

/

2

"

 20,000 

1

1

/

2

"  2" 2

1

/

2

"

LBC Series Models: One (1) Year Limited Warranty
Visit www.amtrol.com for complete warranty details.