Watts MGH User Manual
Series g, gh, mg, mgh, Thermostatic radiator steam traps, For steam heating applications
For Steam Heating Applications
ES-G/GH/MG/MGH
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Watts product specifications in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements,
please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials with-
out prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.
Operation
The Series G, GH, MG, MGH's Balanced Pressure-Duplex
Phosphor Diaphragm is a highly sensitive modulation unit
thermally programmed to provide accurate steam conserving
operation at all pressure temperature points within its range
of operation.
A special liquid, hermetically vacuum-sealed, is employed in a
unique duplex design. The volatile characteristics of this liquid,
with a lower boiling point than that of water, create a higher
internal pressure for a given steam temperature. This
pressure/temperature relationship causes the duplex diaphragm
to expand uniformly, closing the orifice opening in a replaceable
stainless steel seat with a self-centering corrosion-resistant and
hardened stainless steel diaphragm valve. In the presence of
lower temperature condensate and/or non-condensate gases,
the stainless steel valve is withdrawn by the internal condensing
of the duplex diaphragm liquid, allowing full discharge of any
condensate of noncondensables. The diaphragm quickly recy-
cles closed in the presence of steam.
Series G, GH, MG, MGH
Thermostatic Radiator Steam Traps
Sizes
1
⁄
2
" – 1" (15 – 25mm)
For operating pressures up to 65psi (4.5 bars)
Series G, GH, MG, MGH Thermostatic Radiator Steam Traps
are designed to remove condensate, air and non-condensable
gases from heating systems, while still sensitive enough to
close tightly in the presence of steam. The balanced pressure
duplex phosphor bronze diaphragm is a highly sensitive modu-
lating unit thermally programmed to provide accurate steam
conserving operation. Available in a choice of various body pat-
terns including angle, straightway, left hand corner, right hand
corner, vertical and vertical double union.
Features
• Rugged brass construction with union inlet. Duplex
phosphor bronze diaphragm sensitive within 3˚F
• Hardened stainless steel valve
• Stainless steel valve seat
• Diaphragm and seat both replaceable
• Uniform operation within pressure range
• Superior operation under highest vacuum
• Each trap factory tested
• Standard patterns in
1
⁄
2
",
3
⁄
4
", and 1" (15, 20, 25mm)
Applications
Model G and GH – 25” HG vacuum to 25psi
• Low pressure and vacuum heating
• Convectors
• Unit Ventilators
• Radiators
• Fin pipes
• Drip points
• Air vents
Model MG and MGH – 25” HG vacuum to 65psi
• Medium pressure heating equipment
• Process equipment
• Sterilizers
• Autoclaves
• Tracer lines
• Cooking equipment
Specifications
The thermostatic/radiator steam trap shall be installed as indi-
cated on the plans. The steam trap shall have a operating pres-
sure of up to 65psi. The trap body shall be manufactured out of
rugged brass, the diaphram shall be of duplex phosphor bronze
type with hardened stainless steel valve, the seat shall be stain-
less steel. The steam trap shall be a Watts Regulator Company
Series G, GH, MG, MGH.
1GAP