At the time of installation, check to make sure frame is square and has not been damaged in shipment. If the frame is out of square mounting holes will not match fixture anchor locations. Locate rough-in position on wall. If a Metcraft security frame is to be incorporated, cast the frame in place or block in place by conventional construction methods.

  1. Rough-in all plumbing connections required by fixture.
  2. Attach backsplash trim, all through wall plumbing connections and seal.
  3. Attach anchor rods to fixture. Unit is now ready for final positioning.


Plumbing connections on Metcraft security fixtures are made per conventional industry standards. The following details illustrate standard plumbing connections. Please refer to supplementary information covering valve applications. Always follow local plumbing codes.

Basic Floor Outlet Toilet Waste Connection

All waste connections provided by others

Basic Wall Outlet Toilet Waste Connection

All waste connections provided by others

Extended Waste Tube and Adapter Coupling

Basic Sink Waste Connection

Basic Flush Inlet Plumbing Connection


For specific valve applications, Metcraft provides supplemental information which is provided with each shipment. Please refer to these sheets for answers to specific questions on individual valves. In general, Metcraft fixtures are designed to operate under these general guidelines.

  1. All fixtures require water pressure of at least 35 PSI flowing. Recommended maximum pressure 75 PSI.
  2. Flow controls of showers are preset to 2.5 gallons per minute or less.
  3. Flow controls of lavatories are preset to .5 gallons per minute.
  4. Flush all standing water from lines prior to attachment of valve to water supply. Do not leave super chlorinated water in valves or severe damage will occur. Long periods of dormancy can adversely affect valves. The water should be removed from valves during such dormant periods.

For best results from Metcraft A300 Pneumatic Valves, reasonable water quality standards must be maintained. High levels of minerals and sediments in water supply will have detrimental effects on function of these valves.

A300 Pneumatic Valve Installation Instructions

  1. Flush all supply lines thoroughly.
  2. Make sure polyethylene tubing is clear of any debris or water. DO NOT use tubing that has been kinked.
  3. Assemble pushbuttons and bubbler spout to fixture backsplash before securing the fixture to the wall. Install the bubbler inlet fitting to the bubbler inlet.
  4. Mount the valve and bracket assembly to the wall. Choose a location where future access for service and adjustment of the valve will be convenient, bearing in mind that the valve must be located within Seven feet of the pushbutton operators and bubbler outlet.
  5. DO NOT use pipe thread compounds or sealants on Any threads connecting to the valves, valve operators and tubing nuts. Thread sealants are not intended for these connections and may contribute to valve damage or malfunctions and thereby void warranty.
  6. A braided flexible connector is used to connect supply tubing to the strainer check/stop.
  7. Connect 1/2” OD polyethylene tubing to the bubbler head and the valve outlet. Compression connections should only be tightened 1/4 TO 1/2 turn past hand tight. Over tightening with a wrench may cause damage. Make sure tubing is fully inserted into socket before tightening.
  8. Connect 1/8’’ OD tubing to pushbutton diaphragm assemblies and to tube connection on the side of the valve operator closest to the timing adjustment. Make sure tubing is fully inserted in socket on valve operator end before tightening small plastic nut. Small nut should be finger tight but give the tubing a slight tug to see if connection is good. (A vacuum leak at this connection can cause a short cycle time.)
  9. Open supply stop(s) and check the valve and connections for leaks.
  10. Actuate pushbuttons several times to clear air from the valves and tubing. Hold hand in front of bubbler to contain squirting caused by air bubbles. Check water tubing at valve and bubbler for possible leaks again.
  11. Adjust timed cycle of valves as needed. The timing cycle can be adjusted using the timing adjustment located next to the 1/8’’ air tube connection on the side of the valve operator. Some valves have a small screwdriver slot on the end of the adjuster. Turning clockwise lengthens the cycle; Counter-clockwise shortens the cycle. Adjustments should be made in small increment to achieve best results. As the cycle is lengthened, adjustment becomes increasingly sensitive. Timed cycles in excess of 1 minute require infinitely small adjustments.


Symptom: Valve Will Not Shut Off.

  1. Remove 1/8” air tube beside timer. If the valve shuts off after a short time, turn the timer adjustment counter-clockwise several turns. Re-connect the tubing making sure the connection is sealed properly (tubing should not slip or come off if tugged gently). Re-adjust timer for desired cycle time. If the valve still refuses to shut off proceed to step 2.

  2. Turn off water to valve. Remove the valve top by removing the (4) screws securing it. Note the position of the tube connector and timer so the valve top can be properly re-assembled in the same position.

    Remove valve operator exposing the water chamber of the valve. Check the rubber diaphragm assembly for possible debris. Check the diaphragm to be sure the rubber is properly seated into the plastic post.

    Check the hole through the plastic post to be sure it’s free of debris. Turn the diaphragm assembly over and find the small circle near the edge of the rubber. There is a small hole in the middle of the circle that should be free of debris. Rinse the assembly with clean water to remove any debris. Also, rinse the orifice plate and the separator cup in the valve top, making sure the small spring in the separator cup (above the orifice plate) is not dropped or lost. If any part of the diaphragm is damaged, replace the entire diaphragm assembly using part #16426 (PVK-2 diaphragm kit). Clean any debris from the valve base and the valve seat before re-assembling. Re-assemble the valve and adjust the timing to desired cycle length.

Symptom: Valve Will Not Open.
  1. Make sure the water supply is turned on.

  2. Remove the 1/8” plastic tubing from the back of the pushbutton diaphragm and suck on the end. If water flows, the valve is operating properly but there is an air leak in the tubing connections, the tubing or the pushbutton diaphragm. Also, it is possible that the timer has been opened (turned counter-clockwise) so far the vacuum can not be held. Close the timer (turn clockwise) to see if the valve will operate. If yes, adjust timing for desired cycle.

  3. Check the flow control orifice located in the valve outlet fitting to be sure it is not blocked by debris. If blocked, clear debris by blowing air through it from the tubing end of the fitting. Do not force any tools through the orifice as this may damage or distort it and cause improper operation.

  4. Check the pushbutton actuator diaphragm for leakage by removing the diaphragm from the back of the pushbutton and from the air tubing. While holding your finger over the end of the tubing connection to seat it, push the rubber diaphragm toward the back using your finger in place of the pushbutton. If the tubing fitting is sealed properly with your finger, the rubber diaphragm should be held back away from the front of the diaphragm housing. If it returns to the front of the housing, it is not holding a vacuum and must be replaced. This test should be repeated several times before deciding the diaphragm must be replaced as it is difficult to hold your finger over the hole in the tube fitting to properly seal it.

Symptom: Valve Will Only Run A Short Time And Does Not Respond To Timer Adjustment.

  • This is one of the most common complaints. In most cases, this is a result of an air leak in the air tubing connections either at the pushbutton end or the valve end of the tubing. If the tubing is connected using a white plastic nut, gently give the tubing a quick tug. If it comes out of the fitting, re-insert it, making certain it “bottoms out” in the fitting. Using gentle force, tighten the plastic nut one-quarter turn. Repeat as necessary until tubing is held tightly in place.

  • *Some valve operators have a brass barb connection. No tubing nut is used on the operator.*

  • It should be noted that the ends of the 1/8” tubing should be closely checked for splitting or cuts. Also, inspect the tubing to be sure there are no kinks or bends to prohibit air flow within the tubing.

  • If the tubing is damaged or kinked, it must be replaced. The ends of the tubing should be cut square for best results.

Symptom: Bubbler Stream Overshoots The Lavatory Basin (Steady Stream).
  1. Check the flow control fitting to be sure the flow restrictor is in place. The flow restrictor is normally located inside the fitting where the outlet supply tubing is connected to the valve. Penal spouts are designed for a rate of .5 gpm flow rate provided by this flow restrictor. Flow rate can not be adjusted adequately using the inlet stops on the valve.

  2. Check the hole in the spout or bubbler for debris or blockage. The outlet hole of the bubbler must be clear of any obstruction or partial obstruction to form proper height arc. Clear any debris inside the bubbler head by disconnecting the supply tube from the fitting and blowing air back trough the bubbler. Do not use tools or probes through the hole on the bubbler as they may damage the finish or distort the hole, causing an erratic stream. Re-assemble the valve and adjust timing to desired cycle length.

Symptom: Bubbler Stream Does Not Form A High Enough Arc.
  1. Check the flow control fitting for blockage. Clear any debris with air pressure or flushing with clean water. Do not use probes to clear blockage as this may cause damage to the flow restrictor.

  2. Check plastic supply tubing for possible kinks that would restrict water flow.

  3. Make sure inlet stops are open.

  4. Turn off inlet stops and inspect strainer screens for blockage or mineral build-up. Use clean water to rinse away debris. If mineral build-up is severe on the screen, Use a commercial mineral solvent, (like calcisolve or limerase) to clean it. Thoroughly rinse the screen before re-installing it.

Important Valve Re-Assembly Note:
DO NOT tighten the four (4) screws that hold the valve top to the valve base any tighter than 18 inch pounds torque.