45
X. TROUBLESHOOTING (continued)
2. Circulator is On, But Boiler is Off
Display / Status
Recommended Corrective Action
STA1
Circulator
Pre-purge
Burner off
Circulator on
The boiler is warm and circulator is providing residual boiler heat to building:
Check boiler temperature
- The boiler will not start until boiler water temperature is less than the Setpoint (
SP
) minus differential (
df
)
- If boiler water temperature is higher than Start Temperature (
ST_
, default = 140 F) and the Circulator Pre-
purge (
PP_
, default = 2 minutes) time has not expired, boiler start will be delayed until water temperature
drops or time expires. To permit the boiler to start sooner increase Start Temperature parameter. Refer
to Operation Section for additional information.
4. Circulator is On, But Blower is Not On
3. Boiler is On, But Circulator is Off
Display / Status
Recommended Corrective Action
StA 8
Burner on
Circulator off
Domestic Hot Water (DH
W) Priority Forcing Circulator Off
- When there is a DHW heat request wired to the control’s DHW terminal the System Circulator will be
“forced off” for the duration of the DHW heat request. When the DHW heat request ends the System
Circulator “force off” is removed, the circulator can respond normally. When the Priority Time, (
PT_
)
Parameter is set to “
off
” the System Circulator is not “forced off” for a DHW call for heat.
Wiring / Circulator Issue:
- Check wiring for loose connection, miswiring
- Check circulator
Use
STA
(status) Number To guide TroubleShooting
The control will flash “
STA
” followed by a number. Use this number to identify the boiler problem in the table below:
1. Boiler and Circulator Off
Display /
Status
Recommended Corrective Action
STA1
Standby
Burner off
Circulator off
The boiler has not detected a call for heat (
tt
=
off
and dh =
off
).
Check the thermostat:
- When a thermostat call for heat is detected control display “
tt
” will show “
on
”
- Make sure thermostat is calling for heat and contacts (including appropriate zone controls) are closed.
Check for loose connection.
Check the DHW demand:
- When a domestic call for heat is detected “
dh
” will show “
on
”
- Make sure the DHW aquastat contact is closed. Check for loose connection.
Display / Status
Recommended Corrective Action
STA15
Limit Open
Waiting for Limit to Open.
- Check Flame Rollout Switch, in the event of excessive blockage of the boiler section flue passageways
is developed the flame rollout switch will open interrupting power to control P5-4. The main burners will
be extinguished immediately and the circulator will remain on until the thermostat is turned off. If the
flame rollout switch is activated, do not attempt to place the boiler in operation. The source of the
blockage must be corrected and the identical flame rollout switch replaced by trained and skilled
personnel from a qualified service agency.
- Check External Limit.
Summary of Contents for PVG3
Page 14: ...14 Figure 4 Horizontal Vent Installation III Venting continued...
Page 16: ...16 Figure 7 Attic Offset Figure 6 Vertical Vent Installation III Venting continued...
Page 29: ...29 Figure 17 Wiring Connection Diagram VI Electrical continued...
Page 31: ...31 Figure 19 Circulator Zoned System Wiring Diagram VI Electrical continued...
Page 32: ...32 Figure 20 Zone Valve Zoned System Wiring Schematic VI Electrical continued...
Page 34: ...34 Figure 21 Modular Boiler Piping VII Modular Installation continued...
Page 36: ...36 Figure 22 Operating Instructions VIII System Start up continued...
Page 51: ...51 Figure 29 Flue and Burner Cleanout 1 Burner XI Service continued...
Page 54: ...54 XII Repair Parts continued...
Page 56: ...56 XII Repair Parts continued...
Page 60: ...60 XII Repair Parts continued...
Page 67: ...67 SERVICE RECORD DATE SERVICE PERFORMED...
Page 68: ...68 U S Boiler Company Inc P O Box 3020 Lancaster PA 17604 1 888 432 8887 www usboiler net...
