rated according to ANSI Z21.22, have 20 mm 3/4 inch minimum inlets, and 20
mm 3/4 inch outlets for systems where the maximum rate of heat input is
less than 59 kW (200,000 Btuh) 200,000 Btuh. Relief valves rated according
to ASME BPVC SEC IV, or ASME CSD-1, shall have 25.0 mm 1 inch minimum
inlets, and 25.0 mm 1 inch outlets for systems where the maximum rate of
heat input is greater than 59 kW (200,000 Btuh) 200,000 Btuh. The
discharge pipe from the (P&T) valve shall be the size of the valve outlet.
2.3.7
Thermostatic Mixing Valves and Cabinets
2.3.7.1
Mixing Valves
**************************************************************************
NOTE: Require thermostatic mixing valves on hot
water systems where storage temperature is above 43
degrees C (110 degrees F).
**************************************************************************
Mixing valves, thermostatic type, pressure-balanced or combination
thermostatic and pressure-balanced shall be line size and shall be
constructed with rough or finish bodies either with or without plating.
Each valve shall be constructed to control the mixing of hot and cold water
and to deliver water at a desired temperature regardless of pressure or
input temperature changes. The control element shall be of an approved
type. The body shall be of heavy cast bronze, and interior parts shall be
brass, bronze, corrosion-resisting steel or copper. The valve shall be
equipped with necessary stops, check valves, unions, and sediment strainers
on the inlets. Mixing valves shall maintain water temperature within 2
degrees C 5 degrees F of any setting.
2.3.7.2
Cabinets
Cabinets for mixing valves shall be constructed of 1.519 mm (16 gauge) 16
gauge minimum thickness sheet metal of a size to accommodate the equipment
to be installed therein, shall be rigidly assembled with joints welded, and
shall be punched or drilled for the passage of required pipes and services.
Cabinets shall be designed for recessed mounting in wall construction,
with front flush with tile or plaster finish, and shall have flush-fitting
continuously hinged doors. Keyed locks on cabinets located in
neuropsychiatric wards shall be provided. Other cabinets shall be equipped
with friction catch and pull. Doors and trim shall be flush with front of
cabinet and shall be constructed of 1.519 mm (16 gauge) 16 gauge minimum
thickness sheet metal. Doors shall open through 180 degrees. The interior
of the cabinets shall be cleaned, filled and primed, and factory finished
with two coats of gray semigloss baked-on enamel. The exterior of the
cabinets shall be cleaned and filled and factory primed with one coat
baked-on enamel primer.
2.3.7.3
Hardware for Mixing-Valve Cabinets
Each door of cabinets in neuropsychiatric wards shall have a
chromium-plated brass continuous hinge, and shall have a utility lock.
Locks shall be keyed alike and not master keyed in the Attendants (AT) set.
Each inactive door of two-door cabinets shall have two 101.6 mm 4 inch
surface bolts mounted on the inside, one at the top and one at the bottom.
Each door of cabinets in wards other than the neuropsychiatric wards shall
have an approved friction catch and chromium-plated knob pull in lieu of a
utility lock. Hinges shall be of the type specified for neuropsychiatric
ward cabinets.
SECTION 15405A
Page 28
Previous Page
