How to repair a leaking expansion tank

 

Even in the best of boiler systems, the expansion tank can start to leak. The expansion tank is a pressurised system. Pressure variations due to boiler overflow during water expansion and the presence of moving parts can cause the system to deteriorate.

Investigation to find the source of the leak

Use rags or a hairdryer to dry the external areas of the expansion tank and carry out a visual inspection of the surface. If you have difficulty finding the source of a leak in your tank, you can put soapy water around the wet areas and observe the presence of air bubbles. Once the leak has been located, you can start repairing the boiler expansion tank.

Prepare the expansion tank for repair

Before starting work on the expansion tank, it is important to turn off the boiler system power switch, disconnect all electrical plugs and turn off the gas supply (if you have a gas boiler). Close the valve that brings water from the boiler to the expansion tank. Connect a hose to the outlet valve and drain the water from the expansion tank. If you do not have a hose, you can drain the water into a bucket.

Repairing the expansion tank

Circulator leakage

Remove the suction hose from the boiler to the circulator. Remove the circulation pump from the unit and replace the gasket. Replace the circulator by placing Teflon tape around the threads and tightening it with two pipe spanners. Replace the pipe in the same way, putting Teflon tape over the threads and tightening with pipe spanners.

Defective safety valve

The safety valve can be replaced by closing the water supply valve and removing the safety (reducing) valve of the pressure system. Always use two pipe spanners to reduce the possibility of kinking the pipes and causing cracks in the lines.

Leaky pipe connections

If a pipe connection is leaking, the best method to solve the problem is to open the pipe joints and clean the expelled water. Clean the fittings with a cleaning agent and a plastic swab. Be careful when using metal to clean a brass or copper line, as it is a soft metal and can damage the threads. Once the threads and connections have been cleaned, wrap new plumber's tape around the threads of the male end of the pipe and screw the two pipe ends together.

Call the Emergency Plumber Bromley. We are 24 hours available.