Nabic Fig 175
- Boiler connection permanently open
- Minimum water loss on change over
- 90°C Operation
- Dezincification resistant materials
The Fig 175 Three Way Vent Cock has been designed for use on vented hot water systems, to ensure there is a permanent connection from the boiler to the calorifier to atmosphere. Fitting a Fig 175 allows the use of a single common vent pipe, and permits continued operation of the system whilst maintenance is carried out on an individual unit.
The Fig 175 is of gunmetal construction, with all wetted parts manufactured from dezincification resistant materials. A stop incorporated in the gland locates with the plug to ensure that the boiler connection is always open to atmosphere, either via the vent or the drain. End connections have female threads to BS 21 and the DN65 size is also available with flanged boiler and vent connections. Fig 176 malleable iron operating keys, designed to fit the plug squares, can be supplied if required.
- Body Material: Gunmetal
- Maximum Pressure: 7 bar
- Maximum Temperature: 100°C
To provide adequate steam relief capability, vented hot water systems require the fitting of a suitably sized vent pipe in addition to a safety relief valve (Fig 542). The following sizes are specified in BS 779, BS 853 & BS 855.