Camus Hydronics DRH300, Installation, Operation And Service Manual

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2
DR1200 – DR5000: The local thermostat energizes the
motor stop/start relay which closes the initiate contacts
to the variable frequency drive (VFD) which starts to
ramp up the frequency to the 230V 3 phase motor of
the combustion fan. If the VFD is not in fault mode the
frequency will accelerate at the preprogrammed rate
towards maximum speed using the modulating signal
provided by the on board modulating control or the
remote operating system.
8 If temperature high limit, water flow and airflow
switches are closed the fan will run at pre-purge speed
until the pre-purge timer is satisfied. Once complete
the Dynaforce® will target the ignition fan speed.
9 DR 300 – DR 2500 (Direct Ignition): The hot surface
igniter will be energized for 22 seconds followed by
energizing the main valve for 4 seconds. A signal of
0.8dVdc must be recognized by the controller at the
flame sensor to keep the main gas valve in an open
position. The fan is kept at ignition speed until the
stabilization timer is satisfied.
DR 3000 – DR 5000 (Proven Pilot): The Dynaforce®
controller will activate the hot surface igniter for 22
seconds followed by powering the pilot valve for 10
seconds, whereupon a signal of 0.8Vdc must be
recognized by the controller at the flame sensor to
keep the main gas valve in an open position. The fan is
kept at ignition speed until the stabilization timer is
satisfied.
10 If the flame signal is not reached the module will stop
the ignition sequence after the trial for ignition.
11 The fan speed will slowly decrease as the heat request
nears the heat demand. The modulation rate is
controlled via Pulse Width Modulation (DR300 – 800)
and a 4-20mA signal (DR1000 – 5000). If the heat
demand is sustained for a long duration of time the
boiler will get to a point of steady-state and the fan will
rotate at constant speed.
12 When the heat demand is satisfied or is removed the
burner will shut off and the fan speed will ramp up to
the preset Post-Purge speed until the Post-Purge timer
is satisfied.
13 The pump continues to circulate until the post-purge
time is satisfied.
14 The boiler will then go into Standby as it waits for the
next heat demand.
Figure 3: Dynaforce® Ignition Cycle
Note:
1. If a flame signal is detected at the end of the pre-purge
period an error statement to that effect will appear.
2. If at the end of the safety period (6 sec) no flame is
detected the control will go to post-purge to remove the
unburned gas. After this, a re-ignition attempt is started
following the same cycle. The number of re-ignition
attempts is limited to 2 after which a lockout occurs.
3. The burner can only be on continuously for a period of
24 hours. After this the burner is switched off and a
restart sequence follows.
4. The hot surface igniter is de-energized at the end of
the ignition period to allow for ionisation detection.
1.4.1 HEAT TRANSFER PROCESS
1 Burner input continues to increase until water
temperature reaches the set point temperature.
2 Burner input may stabilize at a fixed rate when demand
equals input.
3 Burner input will decrease rate when water
temperature approaches temperature set point.
1.4.2 END OF SEQUENCE
1 Set point temperature is satisfied.
2 Power to the gas valves is turned off.
3 Combustion air fan ramps to a stop over the factory
preprogrammed time period of 60 seconds.
4 Thermostat is now in a standby mode waiting for the
next “Call for Heat”.
WARNING
To minimize the possibility of serious personal injury, fire or
damage to your appliance, never violate the following
safety rules.
WARNING
IMPROPER INSTALLATION, ADJUSTMENT,
ALTERATION, SERVICE OR MAINTENANCE can cause
injury or property damage. Refer to this manual. For
additional information, consult a qualified installer, service
agency or gas supplier.
DO NOT
Do not use this appliance if any part of it has been under
water. The possible damage to a flooded appliance can be
extensive and present numerous safety hazards. Any
appliance that has been under water must be replaced
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance. • Do not touch any electric
switch: do not use any phone in your building. •
Immediately call your gas supplier from a neighbor’s phone.
Follow the gas supplier’s instructions. • If you cannot reach
your gas supplier, call the fire department.
IMPORTANT
Consult and follow local Building and Fire Regulations and
other Safety Codes that apply to this installation. Contact
the local gas utility company to authorize and inspect all
gas and flue connections.
Installation and service must be performed by Camus®
qualified factory trained service technicians.
WARNING
Should overheating occur or the gas supply fails to shut off,
DO NOT turn off or disconnect the electrical supply to the
pump. Shut off the gas supply at a location external to the
appliance.
•
Boilers and water heaters are heat producing
appliances. To avoid damage or injury, do not store
materials against the appliance or the vent-air intake
system. Use proper care to avoid unnecessary contact
(especially children) with the appliance and vent-air
intake components.
•
Never cover your appliance, lean anything against it,
store trash or debris near it, stand on it or in any way
block the flow of fresh air to your appliance.