Clark Reliance Corporation of Strongsville, Ohio, makes level indication and control equipment, and its Reliance boiler trim line covers gauges, valves, water columns and level indicators. A water column mounts beside the boiler and carries the gauge glass, the try cocks, the float and the alarm whistle, so the operator can see and hear the water level.
The Clark Reliance parts listed on BoilerSupplies.com are the GC302, GC310 and GC311 try cocks, the GC450 Series try cock, the RF5M and RF7M water column floats and the alarm whistle. The page also lists the Clark Reliance Steel SG855 Valve Set 3/4" NPT and Ball Checks for 1500 PSI and the SG700 and SG800 Series repair kit. The try cocks and the floats are matched to the column they mount on. The SG855 valve set comes in the one size and rating its name states, and the repair kit is picked by the valve set series it rebuilds, SG700 or SG800.
Key facts
Clark Reliance Corporation of Strongsville, Ohio, makes level indication and control products; its Reliance boiler trim line covers boiler gauges, valves, water columns and level indicators.
BoilerSupplies.com lists Clark Reliance GC302, GC310, GC311 and GC450 Series try cocks and RF5M and RF7M water column floats.
The Clark Reliance Steel SG855 Valve Set 3/4" NPT and Ball Checks for 1500 PSI is a gauge glass valve set with ball checks that close if the glass breaks.
The Clark Reliance SG700 and SG800 Series repair kit carries the seats, stems and packing for a gauge glass valve set.
A try cock is opened by hand to prove water or steam at its height when the gauge glass reading is in doubt.
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One part. Try cock, gauge cock, test cock and petcock all name the small hand valve at a set height that an operator opens to see whether water or steam comes out. The Clark Reliance GC302, GC310, GC311 and GC450 Series on BoilerSupplies.com are that part. Order by the part number on the old cock, or by the column it mounts on.
Look for a part number on the old cock, float or valve set. Failing that, the model of the water column it came off, a photo of the column with the part in place, and the pressure the boiler runs at. For a repair kit, the series of the valve set, SG700 or SG800. Those go in the request.
The RF5M or RF7M float sets it off: it rides on the water inside the column at the same level as the water in the boiler. As the water drops, the float drops with it and works the alarm, and the whistle sounds on low water. A float that sticks or has taken on water no longer moves with the level, and that is when it is replaced.
The kit carries the wear parts for a Clark Reliance gauge glass valve set: the seats, the stems and the packing. Those are the pieces that cut, score or dry out on a valve set that has been worked for years. A kit puts the set back in service without replacing the bodies. Order it by the series of the valve set on the boiler, SG700 or SG800.
The ball checks close the valve set if the gauge glass breaks. The Clark Reliance Steel SG855 Valve Set 3/4" NPT and Ball Checks for 1500 PSI is the pair of valves at the top and bottom of the glass. Each valve carries a ball that seats under the rush of steam or water when the glass lets go. The valves are then shut by hand and the glass replaced.
Give Boiler USA the part number, the column model and the count, over the phone at 1-770-957-9599 or toll free 1-800-780-3776, or through BoilerSupplies.com.
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