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Installation - Honeywell R7795A Manual

Flame safeguard primary controls

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R7795A,B,C,D
DETAILED OPERATING SEQUENCE • INSTALLATION
USE OF RUN/TEST SWITCH (Fig. 9)
(R7795C,D Only)
The RUN/TEST switch is located on the lower left
corner of the R7795C,D Interrupted Pilot Models. The
RUN/TEST switch performs the following functions:
1. DAMPER LINKAGE ADJUSTMENT
The RUN/TEST switch will stop the sequence of the
prepurge just before ignition trials (if in TEST position
prior to ignition trials). This allows adjustment of the
damper linkage. The Prepurge Timer will return to zero
when the RUN/TEST switch is moved to the TEST posi-
tion. The prepurge restarts when the RUN/TEST switch is
returned to the RUN position.
2. PILOT TURNDOWN TEST/INTERRUPTED
PILOT MODELS
The RUN/TEST switch, when moved to the test
position, will stop the sequence of the PILOT IGNITION
TRIAL. This allows testing for spark pickup when the
system is used with an ultraviolet sensor. When stopped in
the TEST position, it is possible to perform the Pilot Turn-
down Test (refer to Pilot Turndown Test of Interrupted
Pilot Models in Checkout section). The safety switch heater
is energized during the pilot flame establishing period
whenever flame is not present. Safety shutdown and lock-
out will occur if the absence of flame exceeds 15 sec-onds
(nominal).
WHEN INSTALLING THIS PRODUCT...
1. Read these instructions carefully. Failure to fol-
low them could damage the product or cause a hazardous
condition.
2. Check the ratings given in the instructions and on the
product to make sure the product is suitable for your
application.
3. Installer must be a trained, experienced flame safe-
guard technician.
4. After installation is complete, check out product
operation as provided in these instructions.
!
CAUTION
1. Disconnect power supply before beginning
installation to prevent electrical shock or
equipment damage.
2. Perform a thorough checkout before leaving

installation.

Follow the burner manufacturer's instructions if sup-
plied; otherwise, proceed as follows.
MOUNTING THE SUBBASE
Locate the subbase where the ambient temperature is
within the specified limits.
Do not mount the Q795A Subbase in any angle that
condensation can accumulate in the R7795 Cover. See
Fig. 6 for mounting dimensions of the Q795A Subbase.
NOTE: If the RUN/TEST switch is moved to the TEST
position during Main Flame Ignition Trial, the R7795
will de-energize the main valve and re-energize the
ignition transformer. When the RUN/TEST switch is
returned to the RUN position, the sequence is returned
to the Main Flame Ignition Trial.
If the RUN/TEST Switch is moved to the TEST posi-
tion during Run, the R7795 will de-energize the Main
Valve and Delayed Main Valve and energize the Ignition
Transformer and Pilot Valve. When the RUN/TEST Switch
is returned to the RUN position, the sequence advances to
the Main Flame Ignition Trial.
!
CAUTION
When a C7012, C7027 or C7035 Flame Detector
is in use, the RUN/TEST Switch should not be
placed in the TEST position from the Main Flame
Ignition Trial or from the RUN portion of the
sequence.
IMPORTANT: MAKE SURE THAT THIS SWITCH IS
IN THE RUN POSITION BEFORE LEAVING THE
INSTALLATION.
Use the Q795A Subbase as a template to mark the
mounting screw locations.
WIRING TO THE SUBBASE
1. Disconnect power supply before beginning installation
to prevent electrical shock or equipment damage. All wir-
ing connections to the subbase must comply with appli-
cable codes, ordinances, and regulations. All wiring to the
subbase must be NEC Class 1 (line voltage) wiring.
2. For normal installations use moisture resistant wire
suitable for at least 194° F [90° C].
3. For high temperature applications, use moisture re-
sistant wire selected for a temperature rating above the
maximum operating temperature for all but the ignition and
F leadwires.
a. For the ignition, use Honeywell specification no.
R1061012 Ignition Cable or equivalent. (This wire
is rated at 350° F [175° C] for continuous duty and
up to 500° F [260° C] for intermittent use.)
b. For the flame detector F leadwire, use Honeywell
specification no. R1298020 or equivalent. (This wire
is rated up to 400° F [205° C] for continuous duty. It
is tested for operation up to 600 volts and break-
down up to 7500 volts.)
IMPORTANT: To avoid possible ignition interference
and nuisance shutdowns, do not run high voltage
ignition transformer wires in the same conduit with
the flame detector wiring.
8
Installation

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R7795dR7795bR7795c