Yoshitake GD-46PP water pressure reducing valve belongs to the GD-46 Series, designed for individual home water supply in collective housing shafts to ensure water is supplied at a regulated pressure. It features a pressure balance structure that keeps the reduced pressure constant without being affected by the inlet pressure. A key maintenance advantage is that water pressure inspections can be performed easily by simply turning the cap upside down while the valve is installed, significantly shortening the construction work period.

Features

1. Reduced noise. Can be used even late at night.
2. Water pressure inspection can be performed easily by turning the cap upside down with the valve installed.
3. Pressure balance structure can keep the reduced pressure at a constant level without being affected by inlet pressure.
4. Attached pressure gauge joint allows a pressure gauge to be installed while water is supplied so that the set pressure can be checked easily.
5. Noise characteristics and flow characteristics conform to the "Quality Criterion on Materials" of Urban Renaissance Agency in Japan.

Specifications

Specification	Value
Nominal size	20A
Application	City water
Inlet pressure	1.0 MPa or less
Reduced pressure	(A) 0.05-0.10 MPa [Standard setting: 0.09 MPa] (B) 0.10-0.22 MPa [Standard setting: 0.20 MPa] (C) 0.20-0.30 MPa [Standard setting: 0.25 MPa]
Minimum differential pressure	0.02 MPa
Maximum pressure reduction ratio	10:1
Working temperature	5-90°C (Without pipe end core)
Minimum adjustable flow rate	0.5 L/min
Rated flow rate	50 L/min (Differential pressure before and after valve: 0.10 MPa or more, without check valve)
Material (Body)	Cast bronze (NPb-treated)
Material (Spindle)	Dezincification resistant material
Material (Valve disc / Diaphragm)	Synthetic rubber/Stainless Steel / Synthetic rubber
Pressure check function	Pressure gauge joint (JIS Rc1/8 thread type)

INFO

• Available with pressure gauge (type A or type D) as an optional extra (for 0.5 MPa). The accuracy of a pressure gauge is ±3% F.S.
• The strainer is 60 mesh.
• The product is set to the pressure reducing valve function when it is delivered from the factory.
• An incombustible material is used for heat insulating material.
• Stop valve is not made with dezincification resistant material.

Dimensions of the Heat Insulating Material

Note: The heat insulating material is common to all GD-46 Series valves. However, no heat insulating material is used for the water stop valve.

How to Adjust the Pressure

1. Screw the pressure gauge into the pressure gauge joint.
2. Remove the cap. By checking the pressure gauge, turn the adjusting screw to adjust the reduce pressure to a desired level.
   • The reduced pressure increases when the adjusting screw is turned clockwise.
   • The reduced pressure decreases when the adjusting screw is turned counterclockwise.
3. After reduced pressure adjustment, attach the cap with the flat face up.
4. Remove the pressure gauge.

TIP

Use a keystone tip screwdriver of 4.5 to 6 mm in nominal width for slotted head screws. Set the screwdriver in the slot of the adjusting screw avoiding the cap nut attached in the center of the screw, and adjust the reduced pressure.

Troubleshooting

Problem	Possible cause	Corrective action
Low flow rate.	- Strainer is clogged. - Setting pressure is low.	- Clean the strainer. - Adjust the pressure by following the adjusting steps.
Secondary pressure is higher than the set pressure.	- The cap is left in water pressure test status.	- Flat surface part of cap should be upside.
External leakage.	- Set screw, valve cap, strainer cap is loose. - O ring or gasket is damaged. - Joint of pressure gauge is loosen.	- Retighten the round head screw, valve cap, and the strainer cap. - Replace the O ring and gasket with a new one. - Remove the joint. Apply seal tape to the thread and attach the joint to the valve body.

Dimensions (mm) and Weights (kg)

Model	Connection (Inlet x outlet)	L	Weight
GD-46PP	R 3/4 × R 3/4	218	1.4
GD-46	G 1 x G 1	-	1.0

(Note: Additional model variations exist within the series with different connections and joints).