Pump Time Delay
There are two versions of the Pump Time Delay. The first is the Economaster II. It is an electronic device that allows the operator to set a variable time (3 to 10 minutes) for the pump to run after the boiler shuts off. See Fig. 40 (A) . The time is
The second version is a fully enclosed solid state TDR with a white jumper that selects one of two time delays. See Fig. 40 (B). If the jumper is on pins 6 and 7 (default) the delay time is 5 minutes. If the jumper is not on pins 6 and 7, the time delay is 10 minutes.
In a conventional system, when the Aquastat is satis- fied, the main gas valve closes, but the pump continues operating. With either time delay relay the boiler pump is programmed to continue running for an optimum period of time in order to absorb the residual heat from the combustion chamber and use it in the system. The pump then shuts off until the next call for heat is received from the Aquastat.
(A)
(B)
Fig. 40: Economaster Time Delay Relays (TDR)
UDB Diagnostic Board
This heater is equipped with a diagnostic board which will indicate faults as they occur. Refer to the following section for instructions on accessing, reviewing and clearing these faults.
Fig. 41: UDB Diagnostic Board
UDB Fault History
To view the fault codes in the UDB history file:
1.Press the UP or DOWN buttons on the membrane switch for 2 seconds to access the fault history.
2.Press either button to scroll through the recorded faults in history.
3.The most recent fault recorded will be the first fault displayed (the last 16 faults are stored in the his- tory, on a rolling basis). There is no time or date stamp associated with these faults.
4.When the history of faults has been exhausted, pushing the UP or DOWN buttons again will roll the fault history over and it will start again.
5.To exit the fault history, wait for 10 seconds and the board will automatically exit the history mode.
To clear the fault history, press and hold both the UP and DOWN buttons for 5 seconds while the power is on.
NOTE: Once the history has been cleared, it cannot be recovered.
Diagnostic information is provided any time a fault is recorded. This information is intended to assist in locating the problem with the heater, but is not exhaus- tive.
If multiple fault conditions occur at the same time, only the fault that caused the heater to shut down will be recorded in the history.
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