Amtrol 747 Installation & Operation Instructions

Warning Label Part No. V56845
installed in this location.
If missing, it must be replaced.

HIGH CAPACITY AIR VENT

INSTALLATION & OPERATION INSTRUCTIONS

Model 747

NOTE: Inspect for shipping damage and notify freight carrier or store where purchased immediately if damage is present. To avoid risk of personal

injury and property damage, if the product appears to be malfunctioning or shows signs of corrosion, call a licensed professional immediately. Current
copies of the Product manual can be viewed at www.amtrol.com. Use proper safety equipment when installing.

THIS IS THE SAFETY ALERT SYMBOL. IT IS USED TO ALERT YOU TO POTENTIAL PERSONAL INJURY AND OTHER
HAZARDS. OBEY ALL SAFETY MESSAGES THAT FOLLOW THIS SYMBOL TO REDUCE THE RISK OF PERSONAL
INJURY AS WELL AS PROPERTY DAMAGE.

Read carefully the product Installation & Operation
Instructions to avoid serious personal injury and

property hazards and to ensure safe use and proper care of this product.

EXPLOSION OR RUPTURE HAZARD The High
Capacity Air Vent must be operated so that the

pressure does not exceed the maximum operating pressure.

The generous use of pipe joint compound when

installing 747 High Capacity Air Vent will foul the
vent’s operating mechanism allowing water to escape. Pipe joint
compound must be conservatively applied to male threads only. Failure
to follow this instruction can result in personal injury from hot water and/
or property damage.

The use of Teflon impregnated pipe compound

and Teflon tape on pipe threads provides lubricity
which can lead to overtightening and breakage. Do not overtighten.
Failure to follow this instruction can result in personal injury from hot
water and/or property damage.

mechanism, it is possible for water to also be discharged. Vent must be
piped to a drain. Failure to follow this instruction can result in personal
injury from hot water and/or property damage.

LOCATE in an area where water from the air vent can cause
property damage.

California to cause cancer and birth defects or other reproductive harm.
For more information go to www.P65Warnings.ca.gov.

When the vent discharges air or if foreign material
from the system fouls the vent’s operating

THIS PRODUCT MUST BE INSTALLED BY A
LICENSED PROFESSIONAL.

This product, like all pressure vessels, can, over
time, corrode, fail, leak and flood. DO NOT

This product can expose you to chemicals
including lead, which is known to the State of

PLEASE READ THE FOLLOWING INSTRUCTIONS CAREFULLY

IMPORTANT GENERAL SAFETY INFORMATION -

ADDITIONAL SPECIFIC SAFETY ALERTS APPEAR IN THE FOLLOWING INSTRUCTIONS.

Description

The AMTROL Model 747 High Capacity Air Vent is designed for
use in liquid systems to purge undesirable free air that otherwise
could impede system performance, increase system operating
cost and contribute to the damaging effects of corrosion. The
accumulation of air in the body of the Model 747 High Capacity Air
Vent causes a float to drop allowing the air to be vented through
an air eliminating orifice. As the liquid level rises in the vent body,
the float also rises, shutting off the flow of venting gases.

Installation Instructions

1. Install the Model 747 Vent in a location where air is expected to
collect or where it is desirable to prevent air accumulation. See
typical applications on back page.

2. Install the Model 747 High Capacity Air Vent with its vent
connection in the top vertical position.

Temperature and Pressure Limits

Maximum Operating Temperature: 250°F (121°C)

Minimum Operating Temperature: 35°F (1.6°C) unless used with
liquid other than water.

Maximum Operating Pressure: 150 psig (10.5 bar)

Operating Instructions

Liquids and additives such as

hydrocarbons, which are aggressive to the
EPDM elastomer seals used in the 747 Air Vent, can cause the
seals to fail and allow uncontrolled discharge of system fluid.
Do not use the 747 Air Vent on systems utilizing such fluids
or additives. Failure to follow this instruction can result in
personal injury from hot water and/or property damage.

The model 747 Air Vent will discharge air

and possibly some liquid during its normal
functioning. Avoid eye, face or skin contact with top area of
Air Vent. AMTROL recommends the vent connection be piped
to a drain to prevent accidental contact with discharging
fluids. Failure to follow this instruction can result in serious
personal injury and /or property damage.

Service Instructions

Corrosion or leakage are indications that

the 747 Air Vent may be at the end of its
useful life or requires maintenance. It should be periodically
inspected and if corrosion or leakage is noted, 747 Air Vent
must be replaced or serviced. Failure to follow this instruction
can result in serious personal injury and/or property damage.

If model 747 Air Vent does not shutoff after air has been vented
off, the seat button may be replaced as follows:

System fluid under pressure and /or at

high temperatures can be very hazardous.
Before servicing, reduce system pressure to zero or isolate
the 747 Air Vent from the system. Allow system to cool below
100°F. Failure to follow this instruction can result in serious
personal injury and/or property damage.

1. Remove the four cap screws that attach the cover to the body.
(Item 1, Fig.1)

2. Remove the cover from the body making sure not to damage
the gasket surfaces on the cover or the body. (Item 2, Fig. 1)

3. Inspect the rubber button and its mating seating surface for
damage or foreign material. (Items 3 & 4, Fig. 1 or 2) If the
rubber button is damaged or has deteriorated, the lever and
button assembly must be replaced.

4. The spring lever and button assembly is removed by pulling the
outer wires of the spring lever out of the holes in the seat yoke.
(Items 5 & 8, Fig. 2) (See Fig. 1 Note). Next, remove the spring
lever and button assembly from the float by pulling it through
the retaining hooks. (Item 6, Fig. 1 or 2).

5. Reverse the procedure in (4) above to install a new lever and
button assembly. If the seat yoke has two sets of holes install
the lever in the smaller off center holes. (See Fig. 3)

6. Thoroughly clean gasket surfaces and install a new gasket.
(Item 7, Fig. 1)

7. Place cover assembly back in place on the body. Replace cap
screws and tighten in a criss cross pattern to 20 ft-lbs. of torque.

8. Open any shutoff valves and return the system to normal
operation.

9. Check for gasket leaks. Retighten bolts or replace gasket if
necessary.

Warranty

Air Vent Model 747: One (1) Year Limited Warranty

Visit www.amtrol.com for complete warranty details.