Weil-McLain BCP-3 manual Troubleshooting

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BCP-3 Installation and Operation Manual

Troubleshooting

No Display or LED Lights

Check the power to the BCP-3. The BCP-3 requires 120VAC power to the Black wires or 24VAC to the right-most terminals. Turn the power off and back on to restore the display. If unsuccessful, make sure that the control's Display Cover is securely mounted to the Base.

System or Outdoor Reads OPEN or SHORT

If the sensor reads Open, short the sensor input terminals. The display should read SHORT. If it doesn’t, the BCP-3 may be damaged.

If the sensor reads Short, remove the wires from the input terminals. The display should read OPEN. If it doesn’t, the BCP-3 may be damaged.

System or Outdoor Sensor Reads an Incorrect Temperature

Remove the sensor wires from the input terminals. The display should change to read OPEN. If it doesn’t, the BCP-3 may be damaged. Take an ohm reading across the detached sensor wires. The ohm reading should correspond to the Temperature Sensor Chart. If the difference is within 5°F adjust the sensor Trim. Otherwise, the sensor may be damaged.

No Heat - All LEDs are OFF

Check the outdoor temperature and the Outdoor Cutoff readings. If the outdoor temperature is above the Outdoor Cutoff, the BCP-3 will not give heat. If the display shows TSTAT OPEN then, check the EXT terminals. If the EXT terminals are not jumped together, the BCP-3 will not give heat.

No Heat - All LEDs are ON

First, make sure that the system pump is running. Remove any connections to the Yellow wires for the Heating System Pump. Test for continuity across the pair of Yellow wires. If the wires are continuous, the BCP-3 is calling for the Heating System Pump to run and the problem is not with the BCP-3. Check the power source to the pump and the pump to determine why it is not circulating.

Second, check the boiler operation and safety control status.

No Heat - System Pump LED ON

Check that the displayed System water temperature is below the Target water temperature minus the Differential. If not, wait until the System temperature falls, and then the stage LED should come on and the boiler should fire. Otherwise, remove all connections from the Blue pair of wires. Check for continuity across the pair of Blue wires using a meter. If the wires are continuous, the BCP-3 is calling for the boiler to run. Check the boiler to determine why it is not firing.

No Heat - Boiler LED ON

Temperature Sensor Chart

The BCP-3 is registering a call for DHW. If the DHW Priority is set to a value other than NO, the Heating System Pump will not run during the priority period of a DHW call. Generally, the DHW will be satisfied before a drop in ambient temperature is noticeable. If the DHW load is large or the boiler can satisfy both loads, change the Priority setting to NO, this will allow the Heating System Pump to circulate hot water to the building while the DHW tank is being satisfied.

TEMPERATURE

Value

(in Degrees °F)

(in Ohms)

-30

117720

-20

82823

 

 

-10

59076

0

42683

 

 

10

31215

 

 

20

23089

25

19939

 

 

30

17264

35

14985

 

 

40

13040

45

11374

 

 

50

9944

 

 

55

8714

60

7653

 

 

70

5941

80

4649

 

 

90

3667

TEMPERATURE

Value

(in Degrees °F)

(in Ohms)

100

2914

110

2332

 

 

120

1879

130

1524

 

 

140

1243

 

 

150

1021

160

842

 

 

170

699

180

583

 

 

190

489

200

412

 

 

210

349

 

 

220

297

230

253

 

 

240

217

250

187

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Contents BCP-3 Hydronic Multi-Stage Boiler ControlSystem Pump Operation Operation ConceptBoiler Operation DHW Pump OperationWiring Power Input WiringWiring Input Terminals Heating System Sensor HSS Installation T1, COMWiring Outputs Wiring the System and DHW Pump Outputs Output Mode TableWiring the Boiler Output BCP-3 Output Modes Wiring BCP-3Menus Startup MenuButton and Navigating Menus Startup OptionsSet Point Available when Startup Control Mode = Set Point Setting the Control to Factory DefaultDefault Display Operating Menu Options Click SET ButtonOptions Off, 30ºF/0ºC to 75ºF/25ºC, On Default 60ºF/16ºC Custom Reset RatioOptions From -40ºF/-22ºC to +40ºF/+22ºC Default 0ºF/0ºC Set Point/Cutoff SET /Set Point/Out. Reset/CutoffSettings/Stage SET /Set Point/Out. Reset/Min. TgtSET /Set Point/Out. Reset/Max. Tgt Stage Menu OptionsOptions Output 1, Output 2, or Output Default Output Single On/Off Boiler and System Pump SettingsRun-On Not Available for 3-On/Off Output Mode Settings/Stage/Lead/RotateSetback Enable/Disable Tstat InputDomestic Hot Water DHW Priority BoostTroubleshooting BCP-3 Plumbing Diagrams Specifications