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7800 SERIES EC7890A,B/RM7890A,B RELAY MODULE

65-0204–1

23

NOTE:

Upon completing these tests, open the master
switch and remove all test jumpers from the subbase
terminals, limits/controls or switches.

Initial Lightoff Check for
Direct Spark Ignition

This check applies for gas and oil burners that do not use a
pilot. It should immediately follow the preliminary inspection.
Refer to the appropriate sample block diagram of field wiring
for the ignition transformer and fuel valve(s) hookup.

NOTE:

Low fuel pressure limits, if used, could be open. If
so, bypass them with jumpers during this check.

1

Open the master switch.

2

Complete the normal checkout of the fuel supply and
equipment as recommended by the equipment
manufacturer.

3

Close all manual main fuel shutoff valve(s). Check that
the automatic fuel valve(s) is closed. Make sure fuel is
not entering the combustion chamber.

4

Close the master switch and start the system with a
call for heat by raising the setpoint of the operating
controller; see Fig. 14 or 7890 sequencing. The
primary sequence should start with the SAFE-START
CHECK sequence.

5

Let the sequence advance through STANDBY and
SAFE-START CHECK to Ignition Trial. Ignition spark
should occur. Listen for the click of the first stage fuel
solenoid valve(s).

6

Let the program sequence complete its cycle.

7

Open the manual fuel shutoff valve(s).

8

Push the reset pushbutton and recycle the program
sequence through STANDBY and SAFE-START CHECK.

9

Watch for the FLAME LED to help determine when the
first stage burner flame is established. If it is
established, proceed to step 15.

J

If the first stage burner flame is not established within
four seconds, or within the normal lightoff time specified
by the equipment manufacturer, close the manual fuel
shutoff valve(s), and open the master switch.

K

Check all burner adjustments.

L

Wait about three minutes. Close the master switch,
open the manual fuel shutoff valve(s), and try again to
light off the burner. The first attempt may have been
required to purge the lines and bring sufficient fuel to
the burner.

M

If the first stage burner flame is not established within
four seconds, or within the normal lightoff time specified
by the equipment manufacturer, close the manual fuel
shutoff valve(s) and open the master switch.

N

If necessary, repeat steps 11 through 13 to establish
the first stage burner flame. Then proceed to step 15.

O

When the first stage burner flame is established, the
sequence will advance to RUN. Make burner
adjustments for flame stability and input rating. If a
second stage is used, proceed to step 18.

P

Shut down the system by opening the burner switch or
by lowering the setpoint of the operating controller.
Make sure the burner flame goes out and make sure all
automatic fuel valve(s) close.

Q

If used, remove the bypass jumpers from the low fuel
pressure limit and subbase.

R

If a second stage is used, make sure the automatic
second stage fuel valve(s) has opened, check the
lightoff as follows. Otherwise proceed to step 19:

a.

Open the manual second stage fuel valve(s).

b.

Restart the system by raising the setpoint of the
operating controller.

c.

When the first stage burner flame is established,
watch for the automatic second stage fuel
valve(s) to open. Observe that the second stage
lights off properly.

d.

Make burner adjustments for flame stability and
input rating.

e.

Shut down the system by lowering the setpoint
of the operating controller. Make sure the burner
flame goes out and all automatic fuel valve(s)
close.

T

Restart the system by closing the burner switch and/or
raising the setpoint of the operating controller. Observe
that the burner flame is established during PILOT IGN,
within the normal lightoff time specified by the
equipment manufacturer.

Measure the flame signal. Continue to check for the proper
signal, see Table 5, through the RUN period. Any pulsating or
unsteady readings will require further attention.

Return the system to normal operation.

IMPORTANT

Make sure all readings are in the required ranges
before proceeding.

NOTE:

Upon completing these tests, open the master
switch and remove all test jumpers from the subbase
terminals, limits/controls or switches.

Pilot Turndown Test
(All Installations Using a Pilot)

Perform this check on all installations that use a pilot. The
purpose of this test is to verify that the main burner can be lit
by the smallest pilot flame that will hold in the flame amplifier
and energize the FLAME LED. Clean the flame detector(s) to
make sure that it can detect the smallest acceptable pilot
flame. If using Ampli-Check™ or Self-Checking Amplifier and
1M ohm/volt meter, the flame signal will fluctuate every time
the amplifier does a self-check or a shutter check.

NOTE:

Low fuel pressure limits, if used, could be open. If
so, bypass them with jumpers during this test.

1

Open the master switch.

2

Close the manual main fuel shutoff valve(s).

3

Connect a manometer (or pressure gauge) to measure
pilot gas pressure during the turndown test.

4

Open the manual pilot shutoff valve(s).

5

Close the master switch and start the system with a 

call

for heat by raising the setpoint of the operating
controller. The primary sequence should start and
PILOT IGNITION should begin.

Summary of Contents for 7800 Series

Page 1: ...umpers GENERAL The Yamatake Honeywell EC7890A B RM7890A B is a micro processor based integrated burner control for automatically fired gas oil or combination fuel single burner applications Except whe...

Page 2: ...onnection between the subbase and the control panel or the equipment The earth ground wire must be capable of conducting the current to blow the 20A fuse or breaker in event of an internal short circu...

Page 3: ...urface corrosion 2 Range of allowable operating frequencies is 45 to 66 Hz 3 2000 VA maximum connected load to 7890 Assembly Environmental Ratings Ambient Temperature Operating 40 F to 140 F Storage 6...

Page 4: ...er if the detection system fails h When an R7861A is used with an EC7890B the application requires the use of a step down transformer See Fig 14 Plug in Flame Signal Amplifiers Applicable Flame Detect...

Page 5: ...NAGER part no ZM7850A1001 Network Interface Unit part no Q7700B1004 Communication Interface ControlBus Module part no QS7800A1001 ControlBus 5 Wire Electrical Connector part no 203541 DATA CONTROLBUS...

Page 6: ...2 155 BURNER CONTROL THREADED MOUNTING HOLES 2 10 32 UNF 1 25 FLAME ROD TARGET CERAMIC INSULATORS IGNITION ELECTRODE Q179C ONLY BRACKET M1983 3 1 8 79 1 21 32 42 1 13 32 36 3 8 10 1 2 13 1 1 16 27 25...

Page 7: ...11 BSP P1 INTERNAL THREADS DIN APPROVED C7035A1064 HAS 1 2 14 BSP F INTERNAL THREADS MODEL AVAILABLE WITH 12 FOOT 3 66 METER LEADWIRES 2 3 INSERTION DEPTH 6 FOOT 1 83 METER LEADWIRES 2 3 M1945A 2 5 8...

Page 8: ...nal system fault occurred c Main valve terminal is not energized d No flame present and configuration jumper is selected for lockout e Pilot valve terminal is not energized SAFETY PROVISIONS Internal...

Page 9: ...tinually through STANDBY to detect any possibility of a runaway detector or a flame If a flame exists a safety shutdown occurs A standard amplifier is energized continually through STANDBY if a flame...

Page 10: ...f part 15 of FCC rules which are designed to provide reasonable protection against such interference when operated in a commercial environment Operation of this equipment in a residential area is like...

Page 11: ...must be capable of conducting the current to blow the 20A fuse or breaker in event of an internal short circuit The 7890 needs a low impedance ground connection to the equipment frame which in turn n...

Page 12: ...AY TO SWITCH THE F LEAD THE RELAY MUST HAVE GOLD CLAD OR GOLD FLASH CONTACTS AND A 120 VAC COIL POWER THE RELAY COIL FROM THE Q7800 SUBBASE TERMINAL 8 CONNECT THE RELAY CONTACTS BETWEEN THE F LEAD OF...

Page 13: ...ION TRANSFORMER MAIN VALVE 1 Q7800 2 2 3 3 5 4 L2 FOR A CONTINUOUS OR STANDING PILOT INSTALL AN EXTERNAL RELAY TO SWITCH THE F LEAD THE RELAY MUST HAVE GOLD CLAD OR GOLD FLASH CONTACTS AND A 230 VAC C...

Page 14: ...for electrical signal voltage probes 3 Make sure no subbase wiring is projecting beyond the terminal blocks Tuck in wiring against the back of the subbase so it does not interfere with the knife blad...

Page 15: ...required checkout tests Installing The Flame Detector NOTE Table 2 and Fig 13 list the flame detection systems available for use with the 7890 Make sure the correct combination of amplifier and flame...

Page 16: ...b 2a EARTH GROUND C7076A OR C7076D TERMINAL BLOCK L2 COMMON L1 HOT G F X X FLAME ROD G F X X PHOTOCELL 1 FLAME DETECTOR LEADS ARE COLOR CODED THE BLUE LEAD MUST BE CONNECTED TO THE F TERMINAL AND THE...

Page 17: ...Up Safe Start Check The 7890 verifies that a flame does not exist and proceeds into the Ignition Trial If a flame is present the 7890 will recycle to the STANDBY period If the critical loads are not i...

Page 18: ...a jumper on the subbase 3 Before continuing to the next test be sure to remove the test jumper s used in the previous tests 4 Replace all limits and interlocks not operating properly Do not bypass lim...

Page 19: ...mper s WARNING Make sure all manual fuel shutoff valves are closed MPORTANT Low fuel pressure limits if used can be open Bypass them with jumpers for the remaining Static tests if required Table 4 Sta...

Page 20: ...mum sensitivity 0 300 Vac capability 0 6000 ohm capability 0 10 Vdc capability Checkout Summary Preliminary inspection all installations Flame signal measurement all installations Initial lightoff che...

Page 21: ...the peaks and valleys caused by the self checking operation 6 The meter reading must be as specified in Table 5 after all tests are completed and all adjustments are made As an option the flame signal...

Page 22: ...on the subbase and close the master switch and return to step 4 7 When the pilot ignites measure the flame signal If the pilot flame signal is unsteady or approaching the 1 25 Vdc minimum value adjus...

Page 23: ...for flame stability and input rating If a second stage is used proceed to step 18 P Shut down the system by opening the burner switch or by lowering the setpoint of the operating controller Make sure...

Page 24: ...itches L Run the system through another cycle to check for normal operation M Return the system to normal operation Ignition Interference Test All Flame Rods Test to be sure that a false signal from a...

Page 25: ...or Ignition Spark Response Test All Ultraviolet Detectors Test to be sure that the ignition spark is not actuating the FLAME LED 1 Close the pilot and main burner manual fuel shutoff valve s 2 Start t...

Page 26: ...uence status messages indicating INITIATE STANDBY SAFE START CHECK PILOT IGN and RUN The selectable messages also provide visual indication current status and historical status of the equipment such a...

Page 27: ...line voltage is at a sufficient level for proper operating parameters STANDBY The LED indicates the burner status POWER The burner can be placed in STANDBY by opening the burner switch or if the opera...

Page 28: ...Wanchai Hong Kong Home and Building Control Honeywell Limited Honeywell Limit e 155 Gordon Baker Road North York Ontario M2H 2C9 Honeywell Latin American Division Miami Lakes Headquarters 14505 Comme...

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