Guidelines for gas boiler repairs

In order to repair a faulty or non-operating boiler it is first necessary to determine the extent of the problem. Evaluating problems with boilers should begin by checking for any residual water in the area of the boiler.

If water or excessive moisture is noted on floors or walls, the problem may be associated with the boiler tank or water line fittings. This can be checked by opening a hot water valve and allowing water to flow into the tank, and through the water lines.

If water is escaping from the boiler tank, most likely the tank will have to be replaced. However, there are instances where a tank can be repaired if the problem is minor in nature. The tank can be drained, opened to vent, and a faulty seam could be repaired by welding or patching. If the tank must be replaced, be sure to close the main water supply valve before disconnecting any water lines. In addition, close the natural gas valve prior to disconnecting that line from the heater control box. Remove all flexible lines, bracing and hold downs prior to removing the tank.

If water is noted at any of the water line fittings, the fittings will have to be disconnected, removed and replaced. In some instances, repairs to the fittings can be made by shutting off the water supply to the boiler and draining the tank. When re-filling a boiler tank, be certain the emergency valve is open. This will prevent air from getting into the water lines and reaching any hot water fixtures at high pressure. Where water is noted at the inlet water line, check the valve for integrity. If there are signs of corrosion or moisture, the valve must be changed. The replacement valves should be of the ball-type only, and not of the gate valve type, since these will collect debris in a relatively short time.

Plumbing connections should be made using plumber’s tape or water resistant pipe compound at the connections. Be sure to include a union fitting at the cold water supply line, in line with the shut off valve. This will allow the tank to be replaced in the future without interrupting other plumbing connections.

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