FAQ - Hydronic Heating Systems

BOILER: GV PROBLEM: Red Valve/Flame Light Flashing.  
  
SOLUTION: Check wiring on gas valve. Check Amp read on ignitor (4.25-4.75) and replace if needed. If still flashing, check gas valve.

BOILER: GV PROBLEM: Boiler Shuts Down on Pressure Drop to Frosting Up on Air Intake.  
  
SOLUTION: Extend the vent pipe out 12" - 14" or so from the house, or disconnect intake air pipe from boiler in basement.

BOILER: HE-VHE - Hot Surface Ignition. PROBLEM: Ignitor Glows - Main Burners Do Not Light.  
  
SOLUTION: Check for 24V across "MV" Terminals on ignition control - if no 24V-replace ignition control (Part #WML511-330-129) OR Check Amp draw on ignitor - old style ignitors should be 4.25-4.75 Amps, new style ignitor kit should be 3.5-4.0 Amps. If readings are less, then replace ignitor (Part #WML511-330-184).

BOILER: HE-VHE - Hot Surface Ignition. PROBLEM: Ignitor Glows - Main Burners Do Not Light.  
  
SOLUTION: Make sure ignition control ground wire is attached - Check flame sensor on White Rodgers systems - also check for proper air differential* and if o.k., replace ignition control. On Fenwal systems-replace ignition control with new Fenwal to Gold Control conversion kit (Part #WML510-811-218). *If air differential does not check out, look for problems in the following areas: Blower Housing Flaking-VHE; Flue Collector Clogged Up-VHE; Blockage in Sensing Tubes-VHE; Blower Motor at Slow RPM-HE/VHE.

BOILER: HE-VHE-Spark Ignition. PROBLEM: Pilot Lights-Main Burners Do Not Light.  
  
SOLUTION: Assuming 5 In. W.C. Inlet Natural Gas Pressure-Jumper Holes 2 & 4 on Gas Valve - If gas valve opens and flame sensor is totally engulfed by pilot flame and sensor is fit snugly in gas valve socket - then replace flame sensor (Part #WHR3098-149)

BOILER: HEII PROBLEM: Red Valve/Flame Light Flashing.  
  
SOLUTION: Check for loose wire connections. Also check for 24V across gas valve terminals during ignitor warm up. If no 24V, replace module. If there is 24V, check Amp read on ignitor (4.25-4.75) and replace if needed.

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