U.S. Boiler Company RSAH Series, Installation, Operating And Service Instructions

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41
110891-02 -5/22
RSAH Installation & Service Manual
Troubleshooting Flow Chart 2 – Burner Will Not Shut Down
Is the
Red LED (LOW
WA TER) On?
NO
YES
The Control is
Sensi ng
Low Water.
WARNING!
TURN OFF POWER TO BURNER IMMEDIA T ELY!
CAUTIO N – ALWAYS ALLOW A BOILER T O FUL LY COOL
BEFOR E ADDING WA T ER.
� Recheck wiring. Make sure that burner is wired to
B1. Burner should never fire when red or yellow
Is eit h er
Yellow LED
On?
YES
The Control h as
Reached T ar g et
or High Limit
T em p erature.
LED is lit.
NO
Is the
Th ermostat
( T-T) Calli ng
for Heat?
YES
The C ontrol is
O p erati ng
Normally.
NO
The burner will continue to fire when there is a call
from the thermostat or external z one.
Is the External
Zone (ZC - ZR )
Calling for
Heat?
YES
The Control is
O p erati ng
Normally.
NO
Is the
Low Limit Dial
NO
Set to O FF ?
� Check temperature displa y. When the Low Limit is
set, the HydroStat will fire the burner until the
temperature reaches the Low Limit Setti ng.
YES
Is t h ere
120 V AC between
NO
B1 and B 2?
Rec h e ck
Wiring.
When there is no call to fire the burner, the volta g e
should be 0 volts between B1 and B 2.
� Make sure the burner is wired to B 1.
YES
Re p lace
Control.
If there is no call for heat (from T-T , ZC - ZR or Low
Limit), there should be 0 V AC between B 1- B 2.
� If there is voltage between B1-B2, the control
should be re p lace d.
Troubleshooting Flow Chart 1 - Burner Will Not Shut Down
11
Troubleshooting
(continued)