Nordyne R-410A Adjustment of Refrigerant Charge, Seer Split System Heat Pump Orifice Usage

2.With compressor running in heat mode, first jump the “T2”-”DFT” test pins. This will indicate to board that defrost T-stat is closed. Defrost T-stat closes at 32°, opens at 68°.

3.Next jump the “Test” pin to “C” on terminal strip.This will initiate defrost test in 5, 10 or 15 seconds (This is determined by 30, 60 or 90 minutes defrost pin settings). Factory setting will be 30 minutes.

4.When the reversing valve shifts to the defrost mode, quickly remove jumper from “Test”-”C”. If the jumper is not removed within a 5 second period, the defrost test will terminate. Unit will continue to stay in defrost mode Until :

A)Board recognizes that defrost sensor has reached 68° and opened or

B)“T2”-”DFT” jumper is removed or

C)10 minutes have elapsed (board override)

If the above steps will not initiate a defrost, replace the defrost board.

Anti Short Cycle Timer Test

The 5 minute time delay feature can be bypassed or shortened to 1 second by jumping the “Test” to “C” terminal.

Note: If jumper is left on the “Test” to “common” pins permanently, the defrost cycle will become inoperable.

Optional Equipment — A functional checkout should be performed in accordance with the checkout procedures supplied with the equipment.

Adjustment of Refrigerant Charge:

CAUTION:

Split system heat pump equipment containsliquidandgaseousrefrigerant under pressure. Adjustment of refrigerant charge should only be attempted by qualified, trained personnel thoroughly familiar with the equipment. Under no circumstances should the homeowner attempt to install and/or service this equipment. Failure to comply with this warning could result in equipment damage, personal injury, or death.

NOTE: The following Refrigerant Charging Charts are applicable to listed assemblies of equipment and at listed airflows for the indoor coil.Assemblies of indoor coils and outdoor units not listed are not recommended.

13 SEER SPLIT SYSTEM HEAT PUMP ORIFICE USAGE

Model	Restrictor Bore Size (in.)		System Charge
Number	Indoor	Outdoor	R-22 (oz.)
1-1/2 Ton	.050	.042	112
2 Ton	.055	.045	138
2-1/2 Ton	.065	.048	145
3 Ton	.073	.052	168
3-1/2 Ton	.077	.055	243
4 Ton	.080	.058	248
5 Ton	.089	.062	248

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