3. Valves. Flashcards
- Assume a diaphragm-type flushometer valve on a water closet runs continuously. What are some of the probable causes of this condition?
Possible causes of this condition are:
- The by-pass is clogged;
- Valve is out of adjustment;
- Foreign object is on main or auxiliary valve seat;
- Main or auxiliary valve seat washers are worn.
- What type of automatic safety device is commonly used for showers in a school or industrial building?
A thermostatically controlled shower mixing valve is commonly used on installations of this type.
- A water closet is equipped with a foushometer valve. What are probable causes if an insufficient volume of water is obtained for satisfactory operation of the bowl?
f1. The shut-off valve or control stop may be throttled down too much.
2. There may be insufficient water pressure.
3. The supply pipe may be too small.
- What are two potential noise creating points in a flushometer valve installation?
Objectional noise may be the line noise at the shut-off valve or control stop or the shut-off noise at the valve seat caused by the sudden restriction of water flowing at high velocity when the valve is approaching its seat.
- Boiler safety valve requirements.
In most states, only spring loaded pop-off safety valves are permitted on steam boilers. Most spring-loaded pop-off safety valves used on low pressure steam boilers have no operator adjustments that could affect normal operation.
- How shall you choice boiler safety valve by capacity?
The safety valve capacity must equal or exceed the boiler pound per hour rating. Listed capacity of 6900 Lb. on the data plate mean that valve can discharge steam at 6900Lb./Hr.
- What is total force for low pressure boiler safety valve?
The safety valve disc opens when 15 lbs. or more of steam pressures applied against every square inch of the safety valve disc exposed to the steam.
- Valves identification.
In all cases, water service valves and shutoff valves serving sill faucets, yard hydrants and wall hydrants must be provided with a tag or similar method of identification as to the valve’s purpose. All other valves must be identified if the valve’s purpose is not obvious because of the proximity of the fixture or appliance served by the valve. Identification is often helpful and sometimes critical in locating valves in an emergency in which quick action is necessary.
- What is the correct location for the installation of a temperature relief valve or a combination temperature and pressure relief valve?
Within 2 inches of the tank tapping for necessary thermal circulation to operate the valve.
- What is meant by the B.T.U. rating of a temperature or a temperature and pressure relief valve for a domestic hot water storage tank or automatic storage heater?
The B.T.U. rating for such relief valves refers to their B.T.U. fluid discharge capacity.Relief valves should be selected so that the B.T.U. rating will be in excess of the maximum B.T.U. output of the heater or heaters used.
- What is critical level for flushometer?
1” below valve outlet.
- Part of flushometer between vacuum breaker and spad?
Flushometr tub.
- Vacuum relief valve of pressure tank?
All water pressure tank shall be provided with a vacuum relief valve at the top of the tank that will operate up to a maximum water pressure of 200 psi and up to a maximum temperature of 200*F. The minimum size of such vacuum relief valve shall be 0.50 inch.
