Service - Honeywell RA890G Manual

RA890G
OPERATION AND CHECKOUT • SERVICE
POWER FAILURE
With the burner operating, open and then immediately
close the line switch to simulate a power failure. Burner
should shut down. After a short delay for component check,
burner should restart and operate normally.
FLAME DURING START
The RA90G should shut down on safety during start-up if
a flame or flame simulating condition is detected. Insert
123514B flame simulator into the test jack. Start the system
by raising the controller setpoint or pressing the start button.
CAUTION
1. Only a trained, experienced, flame safeguard
control technician should attempt to service or
repair heating equipment or controls.
2. Under certain conditions, a capacitor between
terminals F and G within RA890G can remain
charged even after the power is disconnected
and the device is removed from the mounting
base. TO AVOID THE HAZARD OF ELEC-
TRICAL SHOCK, ALWAYS USE A SCREW-
DRIVER WITH AN INSULATED HANDLE
AND AVOID TOUCHING THE F AND G
TERMINALS.
3. Never manually push in the RA890 Relays.
GENERAL
1. Repeat all checks required in the Checkout section
when replacing any system component, or when relighting
or restoring power to the system after an extended shutdown
period.
2. The captive mounting screws carry current; always
disconnect power before loosening or tightening the mount-
ing screws.
3. On each service call, check the controller for the
approximately correct calibration and differential; assure
that it is mounted securely (see controller instructions).
4. Never use oil on any part of the RA890G.
5. When cleaning the burner, clean the flame detector
lens.
6. DO NOT MANUALLY PUSH IN THE RA890 RE-
LAYS. This may damage the relays and it is an unsafe
practice because it overrides the protective features of the
relay. Clean relay contacts only as instructed below.
PERIODIC MAINTENANCE
The specific maintenance schedule setup depends on
several factors including type of equipment being controlled,
operating conditions (dirt and heat especially), cost of a
nuisance shutdown, etc. Include the following in any main-
tenance program:
1. Perform a Flame Failure Check and Pilot Turndown
Test whenever the burner is serviced, and at least annually.
60-2035—9
Hold the simulator on terminal F; the flame relay should pull
in and system should lock out within the safety switch
timing. Remove the simulator and reset the safety switch
after it cools.
NOTE: At the completion of all Checkout tests, make sure
that the RA890 is not on safety lockout, the pilot is turned
up to its normal level, and all limit settings are correct.
Operate the system through one normal cycle before
leaving the installation.
2. Inspect and clean the detector and any viewing win-
dows as often as required by soot accumulation and heat
conditions at the detector.
3. Perform a Flame Current Check at least monthly, and
more often when a shutdown may be costly.
4. Clean contacts only when required by failure to oper-
ate properly.
CONTACT CLEANING
CAUTION
Open the master switch before removing the relay
over or before cleaning contacts. Line voltage may
be present on most contacts when power is on.
Field cleaning of relay or timer contacts is not recom-
mended. If they must be cleaned, use only Honeywell
pressurized Contact Cleaner part no. 132569. Honeywell's
chemical analysis laboratory recommends only this cleaner.
Directions for using the cleaner are printed on the can.
IMPORTANT:
1. Do not clean contacts unless absolutely necessary.
2. Use only Honeywell Contact Cleaner part no. 132569.
Do not use any other type of contact cleaner.
3. Use extreme care to avoid bending the contacts or
changing the specifications or configuration in any
way.
4. Do not use abrasive material to clean contacts.
5. Do not use hard paper such as a business card to clean
the contacts.
Do not use other types of contact cleaners. Honeywell's
chemical analysis laboratory tested other pressurized type
contact cleaners but did not approve them for these reasons:
1. The solvents could deteriorate plastic parts and wire
insulation.
2. The cleaners have an oily residue that collects dust and
dirt. The residue breaks down to form various carbonaceous
products. Either result causes early contact failure.
Do not use an abrasive (burnishing tool, sandpaper, stick,
file, etc.) to clean contacts because it can cause early contact
failure for these reasons:
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Service