Weil-McLain AQUA PLUS GL-E223-ADOC 0311 - Manual (Page 33)

AQUA PLUS
indirect
-
fired water heaters
— Product Manual
Troubleshooting
(continued)
Boiler relief valve lifting or weeping
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.
AQUA PLUS
model
Boiler side
volume —
gallons
35 1.6
45 1.9
55 2.2
85 2.5
105 3.5
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 0311
33