LP-551 Rev. 3.9.16
52
LOW WATER BOILER F21
PUMP OFF TIME
Water level in the boiler is low.
1. Check boiler feed water system to be sure it is supplying
make-up water to the boiler system.
2. Ensure all air is bled from the system.
3. Check for leaks in the boiler and system piping and
repair as necessary.
4. Inspect low water cut off probe and wiring for damage
and repair and replace as necessary.
5. Ensure LWCO jumper is intact and properly installed if
boiler does not have an installed external LWCO.
EXTERNAL LWCO F22
PUMP ON TIME
This error is generated when the External
Low Water Cut Off is installed and the water
level in the boiler is low.
When this code is displayed, the boiler will
not respond to a demand for heat. The
bottom line of the display indicates the
status of the pump. The pump will remain on
when this error is displayed.
IF EXT LWCO is installed:
1. Check boiler feed water system. Ensure it is supplying
make-up water to the boiler system.
2. Be sure all air is bled from the system.
3. Check for leaks in the boiler and system piping and
repair as necessary.
4. Inspect low water cut off wiring for damage and repair
as necessary.
5. Ensure EXT LWCO has power applied to the power
input terminals.
6. Press Reset button on LWCO. If error reoccurs, replace
EXT LWCO.
IF EXT LWCO is NOT installed:
Inspect the jumper from terminals 20 and 21 on the Field
Connection Board for damage or loose connections.
GAS PRESSURE F26
PUMP ON TIME
The following switches are optional
equipment that may be installed on boiler.
These devices have indicator lights that
illuminate if tripped.
High gas pressure switch – Trips if there is
excessive gas pressure on the outlet side of
the gas valve and must be manually reset.
Low gas pressure switch – Trips if there is low
gas pressure on the inlet side of the gas valve
and must be manually reset.
1. If an indicator light is illuminated, investigate the source
of the error for that particular switch.
2. With boiler in service mode, measure the gas pressure
in the supply line with a gas pressure meter. Monitor the
gas pressure during both low and high fire conditions for
correct pressure range.
3. If there are no optional switches or none of the indicator
lights is illuminated on the optional switches, use an
ohmmeter to test each of the switches one at a time. Turn
the power off to the boiler and disconnect the switch to
be tested from the boiler to determine which has tripped.
When you find the tripped switch investigate the cause of
the fault based on the purpose of the switch.
PROGRAM ERROR F31
PUMP OFF
There was an error while programming
the control and the memory is corrupt. The
boiler control will not function in this state
and the pump will be off as indicated on
the bottom line. This error only occurs if a
technician is programming the control and
the programming function fails. The only way
to recover from this error is to reprogram the
control. If this error occurs at any time other
than when a technician is servicing the boiler,
the control has failed and must be replaced
by a qualified technician.
The control must be reprogrammed. If programming
does not solve the problem, the control must be replaced.
HARD FAULT COND F41
This error indicates there is an internal fault
in the circuit within the control connected to
the condensate switch.
1. Inspect the ground wires for damage or loose
connections.
2. Inspect the condensate wiring for damage and repair
as necessary.
3. Ensure no high voltage wires are routed in parallel with
the condensate low voltage wiring.
4. Replace control.
HARD FAULT LWCO F42
This error indicates there is an internal fault
in the LWCO circuit.
1. Inspect the ground wires for damage or loose
connections.
2. Inspect the LWCO wiring for damage and repair as
necessary.
3. Ensure no high voltage wires are routed in parallel with
the LWCO low voltage wiring.
4. Replace control.
Summary of Contents for EP-220 VWH
Page 33: ...LP 551 Rev 3 9 16 33 Figure 24 Cascade Master and FollowerWiring ...
Page 34: ...LP 551 Rev 3 9 16 34 Figure 25 Internal Connection Diagram ...
Page 57: ...LP 551 Rev 3 9 16 57 Figure 30 Combustion System Replacement Parts 220kBTU Model ...
Page 58: ...LP 551 Rev 3 9 16 58 Figure 31 Combustion System Replacement Parts 299 399kBTU Models ...
Page 59: ...LP 551 Rev 3 9 16 59 Figure 32 Replacement Parts All Models ...
