U.S. Boiler Company ENHANCED 2 Series, Инструкция по установке, эксплуатации и обслуживанию, Страница: 24 / 60

24
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.
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 Damper is Not Open
Display / Status Recommended Corrective Action
STA15
Limit Open
Waiting for Limit to Open.
- Check Blocked Vent Switch, in the event of a blocked vent or poor draft condition, the blocked vent 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. The source of blockage must be corrected by
trained and skilled personnel from a qualified service agency before resetting switch.
Blocked Vents are caused by a collapsed chimney resulting in full or partial blockage, chimney cross
sectional area too small, height insufficient or cold chimney causing sustained poor draft. Always follow
the recommendations in Section 4, Connect Venting and Appendix B and B1.
- 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. Check IQ Option Panel Display.
3. Boiler is On, But Circulator is Off
Display / Status Recommended Corrective Action
StA 8
Burner on
Circulator off
Domestic Hot Water (DHW) 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.
- When there is DHW heat request and an Outdoor Air Reset IQ Card is installed the System Circulator will be
forced off for the duration of the Reset Card’s Priority Time (
PT_
) parameter. Check Priority Time (
PT_
)
parameter using the Outdoor Air Reset IQ Option Card Adjustment Mode (see Reset Card Adjustment Mode
Instructions).
Wiring / Circulator Issue:
- Check wiring for loose connection, miswiring
- Check circulator