AAON LL-540 - Manual (Page 60)

60
Water Pressure Relief Valve
Overview
ASME Rated, Design Certified and Listed
by C.S.A
.
Used for protection against excessive
pressure on domestic storage tanks or
tankless water heaters, the pressure relief
valve has no temperature relieving element.
Standard setting, 125 psi Size 3⁄4" x 3⁄4"
(20mm x 20mm).
ASME construction and is tested, listed and
certified by the National Board of Boiler and
Pressure Vessel Inspectors.
ANSI Z21.22 “Relief Valves for Hot Water
Supply Systems.”
DESIGN CERTIFIED and listed by C.S.A.
Automatic Air Vent Valves
Automatic
Air Vent Valves provide
automatic air venting for hot or cold water
distribution systems. These vents purge air
that may be in the water system.
The vent valve utilizes a float to actuate the
valve plug which is located at the top of the
valve. Once the air is displaced and the
system pressure is sustained, the valve plug
seals and prevents any water from escaping
from the system.
The float vent can also operate as an anti-
vacuum device since it will permit air to
enter the system when it must be drained. It
can also be installed to permit the separation
and dispersal of air while fluid is actually
circulating in the system.
Overview

Body and cover are brass construction.

Air vent with silicone rubber seal.

Impurities do not usually affect function
as maximum float line of water is always
lower than the valve seal.

Float is high temperature resistant
polyethylene.

Suitable for use with glycol systems.

Can be disassembled for inspection and
cleaning.