Crown Boiler TWB Series, Руководство по установке

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46
13
CAUTION – ALWAYS ALLOW A BOILER TO COOL BEFORE ADDING WATER
The burner will not fire until the low water condition is satisfied.
� Check that the system is filled with water.
� Check that the sensor is inserted fully into the well and contact
between its spring clip and the copper well tube is made.
� Check that the control is tightly clamped to the well.
See pages 38 and 39 for additional troubleshooting information.
The Control is
Sensing
Low Water.
The Boiler has
Reached the
Target
Temperature.
When the ECONOMY function is active, the control monitors heating
demand and establishes Target boiler temperatures below the high
limit setting to conserve fuel. The burner will not fire until the boiler
temperature drops to the automatically calculated Target Temp
Differential.
Troubleshooting Flow Chart 1 – Burner Will Not Fire
Does the
Display Read
?
YES
The Control is
Purging Latent
Heat from the
Boiler.
The Thermal Pre-Purge feature holds off the burner until the
control determines if the latent heat in the boiler can satisfy
the heat call.
NO
Is the
Green LED
(TEMP ACTIVE)
NO
On?
The Control is
Not Powered.
The Temp Active LED will be on at all times when the control is
powered.
� Check for 120 VAC on terminals L1 and L2.
YES
Is the
Red LED (LOW
WATER) On?
YES
NO
Is the
Yellow LED
(HI TEMP)
On?
YES
The Control is
Sensing High
Temperature.
The burner will not fire until the boiler water has dropped to the
high limit differential set-point (10° below high limit setting).
� Check that the high temperature setting is correct.
NO
Is the
Yellow LED
(TARGET)
On?
YES
NO
Is the
Thermostat
(T-T) Calling
NO
for Heat?
Is the
External Zone
(ZC-ZR) Calling
NO
for Heat?
Is the
Low Limit Dial
Set to OFF?
YES
When the low temperature
setting is set to OFF, the
HydroStat will act as a cold
start control. The burner
will not fire unless there is
a call from the thermostat
(T-T) or an external zone
(ZC-ZR).
� Set thermostat to call
YES YES NO
for heat. Burner should
fire.
� If the boiler has a tank-
less coil, set the Low
Temperature Limit to
maintain temperature.
Is There
120 VAC
Between B1
and B2?
YES
The Control
is Operating
Properly.
HydroStat is supplying 120 VAC to the burner circuit.
� Recheck wiring and operation of burner and other limit controls.
NO
Replace
Control
If both the red and yellow LEDs are off and
there is a call to fire the burner, there will be
120 VAC on terminals B1 and B2.
�
If 120 VAC is not present, the control should
be replaced.