R400Y001 – Tool to replace the bonnet on P10 manifold valves

For fitment of P12AX011 Bonnet to P10V Internal Valves

BONNET REPLACEMENT - See Second Picture

1. Remove the protection cap, the manual hand-wheel or the thermostatic actuator from the body of the regulation element.
2. Screw the cover (1) with a hex. 28mm wrench, making sure that the stem (2) has been completely pulled out; completely close the side discharge lockshield valve (3) and open the ball of the valve by rotating the disc (4), always using an hex. 5mm allen key;
3. For R400 valve only. Screw the valve to the plastic bush (5), previously coupled to the reference dowels on the body of the regulation element. The hydraulic seal is ensured by hand tightening onto the rubber washer. For R400H valve only. Directly screw the valve on the body of the regulation element, by using the 30x1,5 thread. The hydraulic seal is ensured by hand tightening onto the rubber washer.
4. Insert the stem (2) up to the stop then, by using a hex. 6mm alllen key, rotate it anticlockwise apply pressure to couple the square bar positioned at the bonnet end.
5. Rotate the stem, remove the bonnet (2) anticlockwise and be sure to maintain the connection; the initial blocking may be very tight as it is a factory seal; when the bonnet becomes loose use the stem (2) to extract it, by balancing the thrust exercised by the water pressure inside the system.
6. By rotating the disc, close the ball of the valve (4) and completely open the lateral discharge lockshield valve (3), always using a hex. 5mm allen key to discharge the water pressure inside the valve.
7. Unscrew the cover (1) with a hex.28mm wrench and disconnect it from the valve body; remove the bonnet from the stem (2) and introduce a new one.
8. Tighten the cover (1) with a hex.28mm wrench; completely close the lateral discharge lockshield valve (3) and open the ball of the valve by rotating the disc (4), always using a hex.5mm allen key.
9. Mount the new bonnet introducing the stem up to the stop (2) and afterwards using a hex. 6mm allen key, tighten it with force.
10. Completely open the lateral discharge lockshield valve (3), using a hex. 5mm, allen key to discharge the water pressure inside the valve.
11. For R400 valve only. Unscrew the valve from the plastic bush (5), which shall be subsequently released from the reference dowels on the body of the regulation element. For R400H valve only. Unscrew the valve from the body of the regulation element, using 30x1,5 thread.
12. Mount the protection cap, the manual hand-wheel or the thermostatic actuator on the body of the regulation element.


Please Note; Periodically lubricate the washers and the stem (2) with silicone based products for the correct maintenance of R400 and R400H valves.

A YouTube video of the replacement method is shown here - <Click Here>


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R400Y001 – Tool to replace the bonnet on P10 manifold valves

  • Brand: Giacomini
  • Product Code: R400Y001
  • Availability: In Stock
  • £33.60

  • Ex Tax: £28.00

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