Lennox International Inc LB-83114C, 61H42 Acaution, Timing Jumper, Defrost Control Components

The defrost control is a solid state control manufacturedby Hamilton Standard.The control providesautomaticswitchingfrom normalheating operationto defrost mode and back.The defrost controlcontainsasolidstatetimerwhichswitchesan

externa] defrost relay through 1/4" male spades mountedon the control'scircuit board.Thecontrol

energizesthedefrostrelayat regular timed intervals.

On some units, a normally open defrost switch placed in series between the defrost relay and the control initiates defrost only when needed at the end of the timed intervals. On other units, the control initiates defrost on demand from the defrost thermostat,

7- Timing Jumper

A factory installed jumper on the circuit board connects terminal Wl on the circuit board to one

of the three timing pins. 8- TST Pins

Each board is equipped with a test pins for use in

troubleshooting the unit. When jumpered together, these pins reduce the control timing to about 1/256 original time.

ACAUTION

Defrost Control Components:

1- 24V Terminal

Terminat 24V receives 24VAC from the control transformer. This terminal powers the control's internal timer and relays. Terminal 24V must be powered at all times to provide HOLD between thermostat demands.

2 COM Terminal

Terminal COM provides 24VAC common. 3- HLD Terminal

Terminal HLD hold the internal timer in place between thermostat demands and altows the unit

to continue timing upon resumption of thermostat demand, tn most units, terminal HLD is connected directly to thermostat demand.

4- OUT Terminal

Terminal OUT controls unit defrost when connected to one side of the defrost relay coil. An internal relay connected to terminal OUT closes to allow external defrost relay to energize and initiate defrost. At the end of the defrost period, the internal relay connected to terminal OUT opens to de-energize the external defrost relay.

5- RST Terminal

This terminal is not functional for the specified application.

6- Timing Pins (T1,T2,T3)

Each of these pins provides a different timed interval between defrosts (30, 60 or 90 seconds). A jumper connects the pins to circuit board terminal Wl. To change the interval between defrosts, remove the jumper from the pin it is connected to and reconnect the jumper to one of the other available pins.

To Place Control in Test Mode:

1- Turn off all power to avoid damaging the circuit board.

2- Make sure all control terminats are connected as shown on unit wiring diagram before attempting to place control in test mode.

IMPORTANT

3- Connect jumper to "TST" pins,

4- Turn indoor thermostat to heat mode and adjust to highest temperature setting.

5- See table 1 for control timings in "TST" mode,

6- Turn on power to unit and re-adjust thermostat. Be sure to remove jumper when test is complete.

TABLE 1

TEST MODE CONTROL TIMINGS

NORMAL	!_ 30+3	60±6	:	90_9	_	14+1,4
OPERATION	MIN	MIN	i	MIN.		MIN.
"TST" PINS	1!7+0r7	14+1A	i	21_+21		3-3_0.3
JUMPERED	SEC.	i SEC	i	SEC*	i	SEC
TOGETHER					!

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