Install Instructions

39
TROUBLE SHOOTING – SERVICE TIPS
Problem Possible Cause Suggested Remedy
System or Boiler Overfilling or
Excessive Make-up Water
(Water Boilers)
Leaks in System Repair Leaks or Replace Piping as Required
Expansion tank (diaphragm or bladder type)
charge pressure not right
Check Charge Pressure, Correct if Required
Air compression tank waterlogged
or diaphragm or bladder defective on
expansion tank
Replace tank
Fill valve not working or set for too high a
cold fill pressure, causing relief valve to weep
Check Fill Valve, Replace if Necessary
Rapid Cycling
(Water Boilers)
Temperature control differential too narrow Adjust Control Differential
Water Hammer On Start-Up
(Steam Boilers)
Sags in Steam Piping or not enough Pitch Correct Piping Condition
Concentric reducers causing condensate pooling Correct Piping
Drip trap failed closed Replace Trap or Trap Element
Dry returns wetted due to new boiler water line
higher than old boiler
Correct Piping or Install Feed System and Traps
No drip line on the back side of a back-pitched
motorized valve
Install Drip Line and Trap
Water Hammer During Mid-Cycle
(Steam Boilers)
Clogged returns on gravity system Clean or Re-Pipe Return Line(s)
Incorrect near-boiler piping causing wet steam
to system
Correct Piping per Manual
Trap failed open, allowing steam to enter returns Replace Trap or Trap Element
{Radiator Hammer} Large radiator may be
vented too quickly
Use smaller Air Vent or Use Two Small Vents in
Place of One Large Vent, One Mounted Higher
than the Other
Long nipple at Hartford Loop Replace with Close Nipple
Water leg or back slope in return line to receiver
tank, causing water pocketing
Correct Piping
Trap installed at receiver tank, causing water
trapping in return
Remove Trap at Tank, Install Drip Traps and
Radiator Traps where Required
Boiler feed pump or condensate pump feed rate
too fast, causing spraying into equalizer
Throttle Flow Rate
No drip on the inlet side of a forward pitched
motorized valve
Add Drip Line and Trap
Uninsulated steam piping, causing excessive
condensate loads
Insulate Steam Pipes
Water Hammer on Shut-Down
(Steam Boilers)
Close nipple on Hartford Loop too high Repipe 2" to 4" (5cm to 10cm) Below Water Line
Uninsulated steam piping in boiler room, but
system piping insulated, causing vacuum
condition on shut-down
Insulate Steam Pipes
Hammering in the Boiler
(Steam Boilers
Poor circulation in the boiler due to sludge
accumulation
Clean and Blowdown the Boiler
No Heat or Poor Heat
Distribution in the Building
(Steam Boilers
Main vents not working
Replace Main Vents, Repiping away from End
of Lines if Needed
Drip Traps failed closed Replace Traps or Trap Elements
Radiator traps failed open, allowing pressurization
of the returns
Replace Traps or Trap Elements
Water legs or back slope in return lines to receiver
tank, preventing air from venting out receiver vent
Correct Piping
Boiler pressure too high, causing air vents to lock
up or blowing water loop seals
Reduce Operating Pressure
Table 10.1 (cont’d): Boiler Troubleshooting