Checkout - Honeywell R4795A Manual

R4795A

CHECKOUT

CAUTION
Use extreme care while testing the R4795; line
voltage can be present on most terminals when the
power is On.
CHECKOUT SUMMARY
The following list summarizes the checkout tests re-
quired for each type of installation. Instructions for each test
are included in this section.
Preliminary Inspection: All installations.
Flame Current Check: All installations.
Pilot Turndown Test: If a pilot must be proved before the
main fuel valves can open.
Hot Refractory Hold-in Test: Photocell oil installations
only.
Ignition Spark Response Test: All ultraviolet detector
applications.
Safe Shutdown Tests: All installations.
Refer to Fig. 2 to 3 for terminal location, and to Fig. 9 and
10 for location of component parts. Loosen thumbscrew to
remove cover.
Fig. 9—Internal components of R4795A.
3K
1K
UNDER
COVER
PLUG-IN
PURGE
TIMER
(ST71A)
SPRING
CLIP FOR
AMPLIFER
PLUG IN AMPLIFIER
(R7289–GREEN–RECTIFICATION)
(R7290–PURPLE–ULTRAVIOLET)
60-2285—7
2K
CAPTIVE
MOUNTING
SCREWS
(10)
TRANSFORMER
Fig. 10—Internal view showing amplifier and
test jack for flame current test.
ST71A
PLUG-IN
PURGE
TIMER
PURGE TIMER
CONNECTORS
PRELIMINARY INSPECTION
Make certain that:
1. Wiring connections are correct and all terminal screws
are tight. Use a meter to check the continuity of all circuits.
2. Flame detector is installed and positioned properly.
Consult the appropriate installation instructions.
3. Ambient temperature at flame detector does not ex-
ceed maximum rated temperature.
4. Correct combination of amplifier and flame detector is
used. Refer to Plug-In Flame Signal Amplifiers in Specifica-
tions section.
5. Burner is completely installed and ready to fire; fuel
lines are purged of air.
SAFETY
6. Combustion chamber and flues are clear of fuel.
SWITCH
RESET
7. Power is connected to system disconnect switch (mas-
BUTTON
ter switch).
8. Safety switch is reset; push in and then release the
green safety switch.
9. All limits and interlocks are reset.
IMPORTANT: Anytime you reset the safety switch, wait at
least one minute after it trips to allow the heater to cool
before pushing in the reset button.
CAUTION
M8679
Make initial pilot lightoff with manual main fuel
shutoff cock closed.
8
Checkout
ARC-GAP IGNITION INTERFERENCE
PROTECTION (R7289 RECTIFICATION
AMPLIFIER ONLY)
AMPLIFIER
CONNECTORS
OPTIONAL
ALARM TERMINALS
TEST JACK
PLUG-IN
AMPLIFIER
M8680