Raypak 302B-902B - Manual (Page 38)

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Fig. 34: Fan-Proving Switch
Fig. 35: Blocked Vent Switch
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.
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.
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.
Fig. 37: UDB Diagnostic Board
Pump Time Delay
The Economaster is a fully enclosed solid state TDR
with a white jumper that selects one of two time
delays. See Fig. 36. 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 the time delay relay the boil-
er 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.
Fig. 36: Economaster Time Delay Relay (TDR)
NOTE: Once the history has been cleared, it cannot
be recovered.