HTP EL-80 - Check Thermostat Circuit(S); Condensate Removal; Final Checks before Starting Boiler; Setting up a Single Boiler

LP-293 Rev. 9.24.15
44
The DHW pump will come on. If the boiler is set up as a cascade
master and you then press the ^ key again, the DHW pump will
shut o. The display will read:
The system pump will come on. Use the ^ and v keys to toggle
between running each pump in the system as required to help
bleed out all entrapped air. Some good indicators that air is
removed include the absence of gurgling noises in the pipes
and pump operation becoming very quiet. Pressing ^ and v
together at any time will return the boiler to normal operation.
i. After the system has operated for ve minutes, eliminate any
residual air by using the manual air vents located throughout
the system.
j. If purge valves are not installed in the system, open manual
air vents in the system one at a time, beginning with the
lowest oor. Close vent when water squirts out. Repeat with
remaining vents.
k. Rell to correct pressure.
F. Check Thermostat Circuit(s)
1. Disconnect the two external wires connected to the boiler
thermostat terminals (low voltage terminal strip).
2. Connect a voltmeter across these two incoming wires
with power supplied to the thermostat circuits. Close each
thermostat, zone valve and relay in the external circuit one at a
time and check the voltmeter reading across the incoming wires.
3. There should NEVER be a voltage reading.
4. If a voltage reading does occur under any condition, check and
correct the external wiring. (This is a common problem when
using 3-wire zone valves.)
5. Once the external thermostat circuit wiring is checked and
corrected if necessary, reconnect the external thermostat circuit
wires to the boiler low voltage terminal strip. Allow the boiler to
cycle.
G. Condensate Removal
1. The boiler is a high eciency condensing boiler. Therefore, the
unit has a condensate drain. Condensate uid is nothing more
than water vapor, derived from combustion products, similar to
that produced by an automobile when it is initially started.
Condensation is slightly acidic (typically with a pH of 3 to 5)
and must be piped with the correct materials. Never pipe the
condensate using steel, copper, brass or other materials that will
be subject to corrosion. Plastic PVC or CPVC pipe are the only
approved materials.
A condensate neutralizer, if required by local authorities, can be
made up of lime crystals, marble or phosphate chips that will
neutralize the condensate. This may be done by the installer or
you may purchase a condensate neutralizer from HTP (7450P-
212).
2. The boiler is equipped with a ¾ female socket weld tting
connection that must be piped to a local drain. It is very important
that the condensate line is sloped downward away from the
boiler to a suitable inside drain. If the condensate outlet on the
appliance is lower than the drain, you must use a condensate
removal pump, available from HTP (554200). This pump is
equipped with two leads that can be connected to an alarm or
another type of warning device to alert the user of a condensate
overow, which, if not corrected, could cause property damage.
3. If a long horizontal run is used, it may be necessary to create
a vent in the horizontal run to prevent a vacuum lock in the
condensate line.
4. Do not expose the condensate to freezing temperatures.
5. It is very important you support the condensation line to
assure proper drainage.
H. Final Checks Before Starting Boiler
1. Read Startup Procedures within this manual for proper
steps to start boiler. (See Startup Report to record steps for
future reference.)
2. Verify the boiler and system are full of water and all system
components are correctly set for operation.
Ensure the boiler is full of water before ring the burner.
Failure to do so will damage the boiler. Such damage IS NOT
covered by warranty, and could result in property damage,
severe personal injury, or death.
3. Fill condensate trap with water.
4. Verify electrical connections are correct and securely
attached.
5. Inspect exhaust vent and intake piping for signs of
deterioration from corrosion, physical damage or sagging.
Verify exhaust vent and intake piping are intact and correctly
installed per Venting Section and local codes.
I. Setting Up a Single Boiler
When power is applied to the boiler, the control rst completes
a power-up systems check. During this time the combustion
fan may run. The display will initially show the current boiler
supply temperature. If a fault is detected during the power-
up test, the control will display the appropriate fault code.
Otherwise, the display will continue to show the boiler supply
temperature and stand-by, waiting for a demand for heat.
When a demand for heat is received, the control begins the
following demand sequence. The boiler rst turns on the
pump. The control will measure the supply temperature.
If it is below the set point temperature minus the ignition
dierential the control will ignite the burner.
After the burner is lit, the control modulates the ring rate
to control the supply water temperature and meet the heat
demand. When the thermostat or indirect water heater
temperature is met, the control will extinguish the burner and
run the combustion fan to purge gasses from the combustion
chamber. In addition, the pump will run for a pump post purge
interval. The control will then be in standby, waiting to process
the next demand for heat.
During this process, the control will extinguish the burner
if it senses a dangerous or unsafe condition. If the control
determines that a dangerous or unsafe condition has occurred,
the control may lock out the boiler and prevent it from igniting
until a maintenance person diagnoses the problem, repairs
it, and resets the control. In the event that the control goes
into lockout, it will show a diagnostic code on the display,
illuminate the LED fault indicator, and close the alarm relay
contacts to aid in recognition of the condition, diagnosis, and
repair.