Weil-McLain Aqua Plus 35 Product Manual page 33

AQUA PLUS
INDIRECT
Troubleshooting
1 Undersized expansion tank?
Insufficient allowance for expansion on the boiler side can cause the boiler pressure relief valve to lift.
The additional quantity of boiler water contained in the outer tank must be considered when sizing the
boiler side expansion tank.
2 Faulty boiler expansion tank?
Is the expansion tank defective, waterlogged or improperly charged?
Check for failed gaskets or bladders, or a faulty Schraeder valve.
Use a tire gauge to check the charge pressure of the tank.
Turn the boiler limit up to a higher setting and let the system run at a higher temperature. This will
simulate maximum expansion in the boiler system.
If the boiler relief valve lifts and/or there is a significant increase in the boiler system pressure, the
expansion tank is flooded or undersized.
3 Faulty boiler relief valve?
Is the boiler pressure relief valve functioning properly? Dirt and water deposits can accumulate under
the valve seat.
4 Faulty boiler fill valve?
Is the valve filling to the correct pressure?
Part number GL-E223-ADOC 0615
-
FIRED WATER HEATERS
(continued)
Boiler relief valve lifting or weeping
— Product Manual
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