Honeywell R4795A Mounting R4795 On Subbase, C7027, C7035, or C7044 Ultraviolet Flame Detector

Page 7

Fig. 6—Flame detector wiring.

R4795A

INSTALLATION

Fig. 7—Alarm terminal connections.

FLAME ROD

PHOTOCELL

 

X

F

 

 

 

 

 

X

F

 

 

 

 

 

 

X

G

 

X

G

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C7012 ULTRAVIOLET DETECTOR

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BLUE

X

F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

YELLOW

 

 

 

 

 

 

 

X

G

 

 

 

 

 

 

 

BLACK

 

 

 

 

 

 

 

 

POWER

 

 

 

 

 

 

 

BLACK

 

 

 

 

 

 

 

 

 

SUPPLY

 

 

 

 

 

 

 

 

 

 

1C7027, C7035, OR C7044 ULTRAVIOLET FLAME DETECTOR

BLUE

X F

WHITE

X G

1C7027, C7035, AND C7044 FLAME DETECTOR LEADS ARE COLOR CODED BLUE AND WHITE. THE BLUE LEAD MUST BE CONNECTED TO THE F TERMINAL AND THE WHITE LEAD MUST BE CONNECTED TO THE G TERMINAL. THIS CIRCUIT IS DC AND THE UV SENSING TUBE IS POLARITY SENSITIVE. REVERSING THE LEADS EVEN MOMENTARILY CAN DAMAGE OR DESTROY THE UV TUBE.

M8686

Mounting R4795 On Subbase

Make sure that the power supply is disconnected. Loosen the thumbscrew and remove the cover (see Fig. 8). Position the R4795 over the Q270 Subbase. Start all ten

mounting screws and tighten uniformly. These screws com- plete electrical circuits (terminal 1 excepted) and hold the R4795 to the subbase.

ALARM TERMINALS (OPTIONAL)

R4795

 

 

 

 

 

 

 

 

N.C. N.O. COM

L1

(HOT)

ALARM

2 POWER SUPPLY

LINE ORL2 LOW VOLTAGE

ALARM

1

1IF A LINE VOLTAGE ALARM IS USED, THE R4795 MUST BE MOUNTED IN A SUITABLE ENCLOSURE.

2POWER SUPPLY MUST MATCH THE ELECTRICAL RATINGS OF THE ALARM. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.

M8687

CAUTION

Do not overtighten the mounting screws because damage to the circuit board can result. Maximum recommended torque is 10 lb-in. (1.13 N•m).

Replace cover and securely tighten thumbscrew.

Fig. 8—R4795 and Q270 Subbase.

CAPTIVE MOUNTING

SCREWS (10)

Q270

SUBBASESAFETY SWITCH RESET BUTTON IN COVER

TERMINAL

 

BLOCKS

 

 

COVER

PURGE TIMER

THUMBSCREW

 

AMPLIFIER

 

M8688

 

 

7

60-2285—7

Image 7
Contents R4795A Flame Safeguard Primary Controls Ordering Information SpecificationsApprovals Terminal Load RatingWiring to Subbase InstallationLocation Retrofitting R4795 Wiring HookupsReplacing RA890E,F,G with R4795A R4795C ReplacementFlame Detector Wiring Alarm ContactsC7027, C7035, or C7044 Ultraviolet Flame Detector Mounting R4795 On SubbaseCheckout Summary CheckoutPreliminary Inspection Pilot Turndown Test Flame Current CheckLimit Action Power FailureIgnition Spark Response Test UV Detectors Safe Shutdown ChecksNormal Operation Refer to TroubleshootingSafety Operation OperationRelay 2K remains in after flame is extinguished Troubleshooting ProceduresRelay 3K does not pull in on a call for heat Relay 3K pulls in but the burner motor does not startContact Cleaning ServiceMiscellaneous problems Periodic MaintenanceService 60-2285-7 Home and Building Control