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ALTA
Combi Installation, Operating & Service Instructions
19
Troubleshooting
(continued)
B. Troubleshooting with Status Numbers
In Operating Mode, use arrow keys ("
" or "
") to reach "
StA
". Display will then alternate between "
StA
" and number
shown below.
Table 19-2: Status Number Explanation
Display
Description
Explanation
0
Self Check
When first powered up control performs an internal check that takes approximately 10
seconds.
1
Standby
No burner demand is present. This could be because there is no call for heat or
because temperature has exceeded set point plus differential. If there is heating
demand, pump(s) will run in standby.
2
Waiting For Air Pressure
Switch To Close
When a burner demand appears, blower starts and waits for the air pressure switch to
close, proving air flow.
3
Prepurge
Once air flow is proven, blower runs for a defined period of time (less than 10s) before
attempting burner ignition.
4
Burner Ignition
System is lighting burner and allowing flame to stabilize after ignition.
5
Calibration
Control system checks to confirm it is properly controlling air fuel ratio. This happens
when boiler is initially powered up and periodically thereafter. When calibration is
required, system checks flame ionization at both intermediate input and at low fire.
This calibration process takes approximately 1 minute and is normally done during a
CH demand.
6
Low Fire Hold
Burner is being driven to low fire immediately following ignition for a short period of
time to minimize likelihood of temperature overshoot if heating load is too small.
7
Rate Limit
Firing rate is being limited due to an abnormal condition, such as:
•
High Supply water temperature,
•
High Differential Water temperature,
•
High Flue Gas temperature,
•
Raised minimum modulation due to loss of flame during run
H24
.
8
Run (Modulate)
Burner is on and is being allowed to freely modulate to match the heating load.
9
Postpurge
Blower runs for a defined period after burner shutdown to clear combustion products
from boiler and vent system.
10
Pump Air Elimination
When the boiler is first powered up, boiler pump and 3-way valve are cycled for
2 minutes to remove air from boiler. Pump air elimination also occurs after there
has been an over temperature Hold. This process may be interrupted by pressing:
!
reset
button.
11
Standby Delay
Boiler is in Hold status and boiler is not running and hold code is stored in history
b
menu. Boiler will automatically restart once condition that caused Hold is corrected.
Refer to Table 19-5 for hold code name, possible causes and corrective action.
12
Lockout
When lockout occurs, boiler will shut down and event is stored in history,
b
, menu.
Once condition that caused the lockout is corrected, boiler remains shut down until
a reset has been performed by pressing:
!
reset
button. Refer to Table 19-5 for
lockout code name, possible causes and corrective action.
13
Boiler On/Off Switch (
A01
)
Burner and pumps have been switched off by parameter, control is disabled via Quick
Menu item
A01
.
14
Warm Weather Shutdown
When Warm Weather Shutdown is enabled, boiler and pumps are prevented from
responding to a CH demand. Boiler and pumps are free to respond to a DHW
demand. Feature not available with local user display
