Giant Condensate

LITTLE GIANT 115V 60Hz Condensate Removal Pump 554405
LITTLE GIANT 115V 60Hz Condensate Removal Pump 554405
$57.99
Time Remaining: 27d 20h 11m
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Little Giant  553455 Mini Split Condensate Pump EC 400
Little Giant 553455 Mini Split Condensate Pump EC 400
$85.59
Time Remaining: 6d 6h 16m
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Little Giant Condensate Pump 1 2 gal 1 50 hp VCMA 15UL
Little Giant Condensate Pump 1 2 gal 1 50 hp VCMA 15UL
$37.99
Time Remaining: 9d 20h 51m
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Little Giant VCMA 15UL Condensate Pump 554401
Little Giant VCMA 15UL Condensate Pump 554401
$39.99
Time Remaining: 12d 20h 54m
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Little Giant Condensate Pump 1 2 gal 1 30 hp VCMA 20ULS
Little Giant Condensate Pump 1 2 gal 1 30 hp VCMA 20ULS
$45.99
Time Remaining: 11d 17h 43m
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Little Giant 554425 VCMA 20ULS Condensate Removal 1 30 HP Pump w Safety Switch
Little Giant 554425 VCMA 20ULS Condensate Removal 1 30 HP Pump w Safety Switch
$54.99
Time Remaining: 2d 4h 9m
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Little Giant CV 10 Condensate Pump Check Valve 599065
Little Giant CV 10 Condensate Pump Check Valve 599065
$8.95
Time Remaining: 22d 22h 37m
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LITTLE GIANT Condensation Removal Pump 554431
LITTLE GIANT Condensation Removal Pump 554431
$60.29
Time Remaining: 27d 20h 11m
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Little Giant Condensate Pump 1 2 gal 1 50 hp VCMA 15ULS
Little Giant Condensate Pump 1 2 gal 1 50 hp VCMA 15ULS
$39.99
Time Remaining: 23d 23h 54m
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LITTLE GIANT CONDENSATE PUMP 2EC SPT NEW
LITTLE GIANT CONDENSATE PUMP 2EC SPT NEW
$60.00
Time Remaining: 18d 19h 35m
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Little Giant Condensate Pump for AC and 90 Furnaces
Little Giant Condensate Pump for AC and 90 Furnaces
$59.99
Time Remaining: 6d 1h 12m
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Little Giant VCMA 20ULS Condensate Pump with Safety Swi
Little Giant VCMA 20ULS Condensate Pump with Safety Swi
$53.88
Time Remaining: 22d 14h 41m
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VCC 20ULS 554200 LITTLE GIANT CONDENSATE REMOVAL PUMP
VCC 20ULS 554200 LITTLE GIANT CONDENSATE REMOVAL PUMP
$55.95
Time Remaining: 18d 18h 43m
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Little Giant VCMA 15ULS Condensate Pump with Safety Swi
Little Giant VCMA 15ULS Condensate Pump with Safety Swi
$48.88
Time Remaining: 29d 22h 41m
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VCMA 15UL LITTLE GIANT CONDENSATE REMOVAL PUMP
VCMA 15UL LITTLE GIANT CONDENSATE REMOVAL PUMP
$45.00
Time Remaining: 13d 22h 24m
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Little Giant Condensate Pump 1 2 gal 1 30 hp VCMA 20ULS
Little Giant Condensate Pump 1 2 gal 1 30 hp VCMA 20ULS
$173.30
Time Remaining: 3d 19h 54m
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Little Giant ACS 5 Condensate Overflow Switch 14940157
Little Giant ACS 5 Condensate Overflow Switch 14940157
$21.95
Time Remaining: 12d 23h 14m
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LITTLE GIANT 115V 60Hz Condensate Removal Pump 554415
LITTLE GIANT 115V 60Hz Condensate Removal Pump 554415
$64.53
Time Remaining: 29d 20h 11m
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Little Giant VCMX 20ULS 230V Nxtgen Condensate Removal Pump
Little Giant VCMX 20ULS 230V Nxtgen Condensate Removal Pump
$48.52
Time Remaining: 6d 20h 39m
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Little Giant Condensate Pump 1 2 gal 1 30 hp VCMA 20ULS
Little Giant Condensate Pump 1 2 gal 1 30 hp VCMA 20ULS
$44.99
Time Remaining: 19d 3h 26m
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Little Giant 554461 VCMA 20ULST 230V Condensate Pump New In Box
Little Giant 554461 VCMA 20ULST 230V Condensate Pump New In Box
$47.00
Time Remaining: 3d 15h 28m
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VCMA 20ULST 554435 LITTLE GIANT CONDENSATE PUMP
VCMA 20ULST 554435 LITTLE GIANT CONDENSATE PUMP
$46.95
Time Remaining: 20d 7h 49m
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Little Giant Condensate Pump NXT GEN VCMX 20ULS Slim
Little Giant Condensate Pump NXT GEN VCMX 20ULS Slim
$59.99
Time Remaining: 25d 1h 52m
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Little Giant 599123 ACS 2 Condensate Safety Switch
Little Giant 599123 ACS 2 Condensate Safety Switch
$15.87
Time Remaining: 6d 3h 7m
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Little Giant Condensate Pump VCMA 15ULST with Tubing
Little Giant Condensate Pump VCMA 15ULST with Tubing
$49.99
Time Remaining: 22d 22h 6m
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VCMA 20ULS LITTLE GIANT 554425 CONDENSATE PUMP
VCMA 20ULS LITTLE GIANT 554425 CONDENSATE PUMP
$43.95
Time Remaining: 3d 5m
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Little Giant  553455 Mini Split Condensate Pump EC 400
Little Giant 553455 Mini Split Condensate Pump EC 400
$85.59
Time Remaining: 6d 6h 18m
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Little Giant VCMX 20ULS C Condensate Pump 554542
Little Giant VCMX 20ULS C Condensate Pump 554542
$52.95
Time Remaining: 13d 21h 43m
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Little Giant VCMA 15ULS Condensate Pump 554405
Little Giant VCMA 15ULS Condensate Pump 554405
$44.95
Time Remaining: 13d 21h 42m
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LITTLE GIANT 115V 60Hz 6Ft Condensate Removal 554401
LITTLE GIANT 115V 60Hz 6Ft Condensate Removal 554401
$59.43
Time Remaining: 4d 22h 6m
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Little Giant VCMX 20ULST Condensate Pump 554550
Little Giant VCMX 20ULST Condensate Pump 554550
$53.95
Time Remaining: 6d 19h 21m
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Little Giant VCMA 15UL Condensate Pump 554401
Little Giant VCMA 15UL Condensate Pump 554401
$41.95
Time Remaining: 13d 21h 52m
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Little Giant VCMX 20ULST WT Nxtgen Condensate Removal Pump with Tubing
Little Giant VCMX 20ULST WT Nxtgen Condensate Removal Pump with Tubing
$48.44
Time Remaining: 6d 20h 44m
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Little Giant Condensate Pump 1 50 hp VCMA 15UL Lot of 5
Little Giant Condensate Pump 1 50 hp VCMA 15UL Lot of 5
$154.95
Time Remaining: 17d 20h 16m
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Little Giant 553711 EC OP K Electronic Condensate Pump
Little Giant 553711 EC OP K Electronic Condensate Pump
$139.41
Time Remaining: 8d 21h 21m
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Little Giant VCL 14ULS Automatic Condensate Pump 553101
Little Giant VCL 14ULS Automatic Condensate Pump 553101
$92.95
Time Remaining: 12d 23h 15m
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LITTLE GIANT 2EC SPT 551025 230 VOLT CONDENSATE PUMP 161113
LITTLE GIANT 2EC SPT 551025 230 VOLT CONDENSATE PUMP 161113
$63.00
Time Remaining: 29d 3m
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Little Giant VCMA 20ULS Condensate Pump 554425
Little Giant VCMA 20ULS Condensate Pump 554425
$48.95
Time Remaining: 6d 19h 21m
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Little Giant VCMX 20ULS 115V Nxtgen Condensate Removal Pump
Little Giant VCMX 20ULS 115V Nxtgen Condensate Removal Pump
$45.58
Time Remaining: 27d 23h 8m
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Little Giant 50195 20 Condensate Removal Pump
Little Giant 50195 20 Condensate Removal Pump
$56.99
Time Remaining: 6d 20h 32m
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little giant condensate unit with verticall pump553211
little giant condensate unit with verticall pump553211
$60.00
Time Remaining: 1d 21h 34m
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Little Giant VCMX 20UL Condensate Pump 554520
Little Giant VCMX 20UL Condensate Pump 554520
$46.95
Time Remaining: 12d 19h 43m
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Little Giant 1 ABS Shallow Pan Condensate Pump 550521
Little Giant 1 ABS Shallow Pan Condensate Pump 550521
$84.90
Time Remaining: 12d 23h 15m
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Little Giant Condensate Pump VCMA 20ULST with Tubing
Little Giant Condensate Pump VCMA 20ULST with Tubing
$54.99
Time Remaining: 19d 3h 26m
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Little Giant VCL 24UL Automatic Condensate Pump 553206
Little Giant VCL 24UL Automatic Condensate Pump 553206
$90.95
Time Remaining: 12d 23h 15m
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Little Giant 1 2 HP 120V Professional Automatic Condensate Removal Pump
Little Giant 1 2 HP 120V Professional Automatic Condensate Removal Pump
$69.99
Time Remaining: 11d 23h 55m
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Little Giant Condensate Removal Pump 554405 1 2 Gal ABS tank 3 prong plug
Little Giant Condensate Removal Pump 554405 1 2 Gal ABS tank 3 prong plug
$84.99
Time Remaining: 23d 23h 34m
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Little Giant VCMA 15UL Condensate Pump 554401
Little Giant VCMA 15UL Condensate Pump 554401
$160.00
Time Remaining: 3d 20h 7m
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Little Giant 599123 48V AC DC 5 Amps Max Auxiliary Condensate Switch with 18
Little Giant 599123 48V AC DC 5 Amps Max Auxiliary Condensate Switch with 18
$8.36
Time Remaining: 21d 14h 41m
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Little Giant EC 400 In Pan Autom Condensate Pump 553455
Little Giant EC 400 In Pan Autom Condensate Pump 553455
$97.95
Time Remaining: 12d 23h 15m
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Little Giant VCMA 15ULST Condensate Pump 554415
Little Giant VCMA 15ULST Condensate Pump 554415
$47.95
Time Remaining: 13d 21h 42m
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Little Giant EC OP K Automatic Condensate Removal Pump 553712 230v Very Quiet
Little Giant EC OP K Automatic Condensate Removal Pump 553712 230v Very Quiet
$125.49
Time Remaining: 6d 6h 34m
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Little Giant VCL 24ULS Automatic Condensate Pump 553201
Little Giant VCL 24ULS Automatic Condensate Pump 553201
$96.95
Time Remaining: 3d 19h 30m
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LITTLE GIANT VCMA 15ULS CONDENSATE REMOVAL PUMP 5G NEW
LITTLE GIANT VCMA 15ULS CONDENSATE REMOVAL PUMP 5G NEW
$74.99
Time Remaining: 28d 9h 11m
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Little Giant 554421 Steel 80 GPH 115V Automatic Condensate Removal Pump VCMA
Little Giant 554421 Steel 80 GPH 115V Automatic Condensate Removal Pump VCMA
$45.72
Time Remaining: 21d 14h 41m
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Little Giant VCMA 15ULT Condensate Pump 554411
Little Giant VCMA 15ULT Condensate Pump 554411
$46.95
Time Remaining: 22d 22h 35m
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Little Giant 2 ABS Shallow Pan Condensate Pump 551020
Little Giant 2 ABS Shallow Pan Condensate Pump 551020
$119.95
Time Remaining: 12d 23h 15m
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Little Giant VCMA 20UL Condensate Pump 554421
Little Giant VCMA 20UL Condensate Pump 554421
$46.95
Time Remaining: 21d 20h 34m
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LITTLE GIANT 554455 CONDENSATE REMOVAL PUMP NIB
LITTLE GIANT 554455 CONDENSATE REMOVAL PUMP NIB
$55.00
Time Remaining: 1d 21h 45m
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VCL 24ULS LITTLE GIANT 553201 CONDENSATE REMOVAL PUMP
VCL 24ULS LITTLE GIANT 553201 CONDENSATE REMOVAL PUMP
$92.95
Time Remaining: 3d 36m
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Little Giant 554425 VCMA20ULS Automatic Condensate Pump
Little Giant 554425 VCMA20ULS Automatic Condensate Pump
$57.22
Time Remaining: 18d 21h 32m
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LITTLE GIANT 553240 BLACK 450GPH AUTOMATIC CONDENSATE REMOVAL PUMP
LITTLE GIANT 553240 BLACK 450GPH AUTOMATIC CONDENSATE REMOVAL PUMP
$200.00
Time Remaining: 20d 10h 48m
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Little Giant VCMA 20ULST Condensate Pump 554435
Little Giant VCMA 20ULST Condensate Pump 554435
$50.95
Time Remaining: 12d 19h 37m
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Little Giant 3 ABS Shallow Pan Condensate Pump 551320
Little Giant 3 ABS Shallow Pan Condensate Pump 551320
$185.95
Time Remaining: 23d 19h 26m
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Little Giant VCC 20ULS Condensate Pump 554200
Little Giant VCC 20ULS Condensate Pump 554200
$62.95
Time Remaining: 13d 21h 43m
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Little Giant 599122 ACS 2 Condensate Safty Switch
Little Giant 599122 ACS 2 Condensate Safty Switch
$19.87
Time Remaining: 6d 3h 6m
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LITTLE GIANT CONDENSATE PUMP MODEL  VCMA 15ULT NEW
LITTLE GIANT CONDENSATE PUMP MODEL VCMA 15ULT NEW
$55.00
Time Remaining: 18d 2h 10m
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Little Giant VCL 45ULS Automatic Condensate Pump 553240
Little Giant VCL 45ULS Automatic Condensate Pump 553240
$219.95
Time Remaining: 15d 2h 43m
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Little Giant 553240 VCL 45ULS Automatic Condensate Pump
Little Giant 553240 VCL 45ULS Automatic Condensate Pump
$239.42
Time Remaining: 18d 21h 31m
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Little Giant 554401 VCMA 15UL Automatic Condensate Pump
Little Giant 554401 VCMA 15UL Automatic Condensate Pump
$50.97
Time Remaining: 18d 21h 31m
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Ez Flo 50193 Little Giant Condensate Removal Pump
Ez Flo 50193 Little Giant Condensate Removal Pump
$53.44
Time Remaining: 18d 18h 25m
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Little Giant 553670 PCS 10 Condensate Removal Pump
Little Giant 553670 PCS 10 Condensate Removal Pump
$191.67
Time Remaining: 18d 21h 31m
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Little Giant 553672 PCR 10 Peristatic Condensate Pump
Little Giant 553672 PCR 10 Peristatic Condensate Pump
$214.37
Time Remaining: 18d 21h 31m
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Little Giant 554411 VCMA 15ULT Condensate Removal Pump
Little Giant 554411 VCMA 15ULT Condensate Removal Pump
$55.80
Time Remaining: 18d 21h 32m
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Little Giant 50192 20 Low Profile Condensate Removal Pump
Little Giant 50192 20 Low Profile Condensate Removal Pump
$65.39
Time Remaining: 6d 20h 17m
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Little Giant 14940157 Auxiliary Condensate Overflow Safety Switch
Little Giant 14940157 Auxiliary Condensate Overflow Safety Switch
$18.90
Time Remaining: 12d 29m
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New Little Giant Condensate Pump VCC 20ULS
New Little Giant Condensate Pump VCC 20ULS
$29.00
Time Remaining: 1d 10h 11m

Little Giant EC OP K Automatic Condensate Removal Pump 553712 230v Very Quiet
Little Giant EC OP K Automatic Condensate Removal Pump 553712 230v Very Quiet
$139.39
Time Remaining: 11d 22h 35m
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Little Giant VCMX 20ULST Nxtgen Condensate Removal Pump with Anti Sweat Sleeve
Little Giant VCMX 20ULST Nxtgen Condensate Removal Pump with Anti Sweat Sleeve
$48.44
Time Remaining: 6d 20h 47m
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Little Giant 554421 VCMA 20UL Automatic Condensate Pump
Little Giant 554421 VCMA 20UL Automatic Condensate Pump
$58.31
Time Remaining: 8d 4h 14m
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Little Giant 554472 VCMA 20ST Condensate Removal Pump
Little Giant 554472 VCMA 20ST Condensate Removal Pump
$77.68
Time Remaining: 18d 21h 31m
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Little Giant 599125 24VAC 5 Amp Auxiliary Condensate Switch with 72 lead wires
Little Giant 599125 24VAC 5 Amp Auxiliary Condensate Switch with 72 lead wires
$18.40
Time Remaining: 21d 14h 41m
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Little Giant 554530 VCMX 20ULS Auto Condensate Pump
Little Giant 554530 VCMX 20ULS Auto Condensate Pump
$62.64
Time Remaining: 18d 21h 31m
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Little Giant 554455 VCMA20ULS Automatic Condensate Pump
Little Giant 554455 VCMA20ULS Automatic Condensate Pump
$72.56
Time Remaining: 18d 21h 31m
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Little Giant 599124 ACS 3 Condensate Safty Switch
Little Giant 599124 ACS 3 Condensate Safty Switch
$30.38
Time Remaining: 6d 3h 7m
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Little Giant 550531 1 ABS Condensate Pump 1 150 Hp 230V
Little Giant 550531 1 ABS Condensate Pump 1 150 Hp 230V
$108.48
Time Remaining: 1d 23h 53m
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Little Giant VCL 45ULS Heavy Duty Vertical Condensate Pump
Little Giant VCL 45ULS Heavy Duty Vertical Condensate Pump
$217.07
Time Remaining: 13d 11m
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Little Giant 554451 VCMA 20UL Condensate Removal Pump
Little Giant 554451 VCMA 20UL Condensate Removal Pump
$61.52
Time Remaining: 18d 21h 31m
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Little Giant 553671 PCT 10 Peristatic Condensate Pump
Little Giant 553671 PCT 10 Peristatic Condensate Pump
$210.93
Time Remaining: 18d 21h 31m
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Little Giant 14940157 ACS 5 Auxiliary Condensate Switch
Little Giant 14940157 ACS 5 Auxiliary Condensate Switch
$34.19
Time Remaining: 6d 3h 6m
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Little Giant 553137 VCL 24S Condensate Pump 1 15Hp 230V
Little Giant 553137 VCL 24S Condensate Pump 1 15Hp 230V
$142.30
Time Remaining: 18d 21h 31m
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Little Giant 551370 3 ABS Condensate Pump 1 12 Hp 230V
Little Giant 551370 3 ABS Condensate Pump 1 12 Hp 230V
$262.52
Time Remaining: 1d 23h 53m
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CONDENSATE PUMP LITTLE GIANT MODEL VCMA 15ULS NEW
CONDENSATE PUMP LITTLE GIANT MODEL VCMA 15ULS NEW
$59.99
Time Remaining: 11d 22h 47m
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Little Giant 553455 Black 25 GPH 115V Condensate Removal Pump with Safety
Little Giant 553455 Black 25 GPH 115V Condensate Removal Pump with Safety
$103.14
Time Remaining: 21d 14h 41m
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Little Giant 554533 VCMX 20 Condensate Removal Pump
Little Giant 554533 VCMX 20 Condensate Removal Pump
$77.54
Time Remaining: 18d 21h 31m
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Little Giant 550532 1 ABS Condensate Pump 1 150 Hp 230V
Little Giant 550532 1 ABS Condensate Pump 1 150 Hp 230V
$107.94
Time Remaining: 1d 23h 52m
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Little Giant 554435 VCMA 20ULST Auto Condensate Pump
Little Giant 554435 VCMA 20ULST Auto Condensate Pump
$64.33
Time Remaining: 3d 23h 46m
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Little Giant 599125 ACS 4 Safety Condensate Switch
Little Giant 599125 ACS 4 Safety Condensate Switch
$32.16
Time Remaining: 6d 3h 6m
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Little Giant 553240 Black 450 GPH Automatic Condensate Removal Pump
Little Giant 553240 Black 450 GPH Automatic Condensate Removal Pump
$235.27
Time Remaining: 21d 14h 41m
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Little Giant 50194 24 Condensate Removal Pump
Little Giant 50194 24 Condensate Removal Pump
$104.83
Time Remaining: 6d 20h 29m
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Giant Condensate
Giant Condensate

Spreading Of Life On Earth

Earth, the third planet from the Sun, is our home planet. Its surface is mostly water (about 70 percent) and it has a moderately dense nitrogen-and-oxygen atmosphere that supports life—the only known life in the universe. From space, Earth appears as a shining blue ball with white swirling clouds covering vast oceans and irregular-shaped landmasses that are varying shades of green, yellow, brown, and white.

Earth orbits the Sun at a distance of about 93,000,000 miles (150,000,000 kilometers), taking 365.25 days to complete one elliptical (oval-shaped) revolution. The planet rotates once about its axis almost every 24 hours. It is not truly spherical, but bulges slightly at its equator. Earth's diameter at the equator is roughly 7,926 miles (12,760 kilometers), while its diameter at the poles is 7,900 miles (12,720 kilometers). The circumference of Earth at its equator is about 24,830 miles (40,000 kilometers). Earth's only natural satellite, the Moon, orbits the planet at an average distance of about 240,000 miles (385,000 kilometers). Some scientists believe that Earth and the Moon should properly be considered a double planet, since the Moon is larger relative to our planet than the moons of most other planets.

Unlike the outer planets, which are composed mainly of light gases, Earth is made of heavy elements such as iron and nickel, and is therefore much denser. Hot at first due to the collisions that formed it about 4.5 million years ago, Earth began to cool. Its components began to separate themselves according to their density. Heavy abundant elements, iron and nickel, formed Earth's core. Outside the core numerous elements were compressed into a dense but pliable (bendable) substance called the mantle. Finally, a thin shell of cool, silicon-rich rock formed at Earth's surface, called the crust or lithosphere. Formation of the crust from the initial molten blob took half a billion years.

Earth's atmosphere is the only planetary atmosphere in the solar system capable of sustaining life. It is made of 78 percent nitrogen, 21 percent oxygen, and a 1 percent mixture of gases dominated by argon. Various theories have been proposed as to the origin of these gases. One theory states that when Earth was formed, the gases were trapped in layers of rock beneath the surface. They eventually escaped, primarily through volcanic eruptions, to form the atmosphere. Water vapor was the most plentiful substance spewed out, and condensed (change from a gas to a liquid) to form the oceans. Carbon dioxide was second in terms of quantity, but most of it dissolved in the ocean waters or was altered chemically through reactions with other substances in the rocks. Nitrogen came out in smaller amounts, but always remained in its present form because it never underwent reactions or condensation. It is believed that for that reason, nitrogen is the most abundant gas in the atmosphere today.

Oxygen only became a part of Earth's atmosphere when green plants came into being. Through the process called photosynthesis, green plants convert carbon dioxide into oxygen. Oxygen is also removed from the atmosphere when green plants, as well as animals, die. As they decay, they oxidize (a process that uses up oxygen). Another more recent theory regarding the development of Earth's atmosphere states that the elements found in it were deposited there by comets. Debris from comets has been shown to have carbon and nitrogen in roughly the same proportion as the atmosphere. During its early development, Earth was the site of repeated comet collisions.

Ninety-nine percent of the atmosphere's mass is contained in the first 40 to 50 miles (65 to 80 kilometers) above Earth's surface. This relatively thin atmosphere insulates the planet by allowing the Sun's visible light to pass through the atmosphere and warm the surface. The resulting heat (infrared radiation) is reradiated from the surface, but is prevented from totally escaping back into space by carbon dioxide, methane, and water vapor in the atmosphere. These so-called greenhouse gases absorb most of this energy and re-emit back to the surface, keeping the planet at relatively stable, warm temperatures. The average surface temperature is 59°F (15°C). While keeping in necessary heat radiation, components in the atmosphere block dangerous forms of radiation from reaching the surface. These include X-rays and ultraviolet radiation, which is absorbed by the ozone layer located at about 15 miles (24 kilometers) above Earth's surface.

The surface of Earth is divided into dry landmasses and oceans. Landmasses occupy roughly 57.5 million square miles (148.9 million square kilometers) of the planet's surface, while oceans cover roughly 139.5 million square miles (361.3 square kilometers). Landmasses are in a constant, though slow, state of change. They move, collide, and break apart according to a process called plate tectonics. The lithosphere is not one huge shell of rock; it is composed of several large pieces called plates. These pieces are constantly in motion, because Earth's interior is dynamic, with its core still molten (liquid) and with large-scale convective (circulating) currents in the upper mantle. This resulting giant furnace beneath the surface moves land no more than a few centimeters a year, but this is enough to have profound consequences. The unending cycle of mountain building (caused by movement of the crustal plates) and erosion (by wind and water) has formed every part of Earth's surface today.

Earth is mostly covered with water. The mighty Pacific Ocean covers nearly half of the globe. The existence of oceans implies that there are large areas of the lithosphere that are lower than others, which form huge basins. Early in the planet's history these basins filled with water condensing (raining) out of the primordial (primitive) atmosphere. Additional water was brought to Earth by impacting comets, whose nuclei were made of water and ice.

The atmosphere has large circulation patterns, and so do the oceans. Massive streams of warm and cold water flow through them. Circulation patterns in the oceans and in the atmosphere are driven by temperature differences between adjacent areas and by the rotation of Earth, which helps create circular flows. Oceans play a critical role in the overall weather patterns of our planet. Storms are ultimately generated by moisture in the atmosphere, and evaporation from the oceans is the prime source of such moisture. Oceans respond less dramatically to changes in solar energy than land does, so the temperature over a given patch of ocean is far more stable than one on land.

The presence of life on Earth is, as far as we know, unique. The origin of life on Earth is not fully understood, but scientists believe amino acids, the essential building blocks of life, formed in the primordial oceans billions of years ago. Over eons, these building blocks combined and evolved into higher and higher life-forms. Life has existed on dry land only for the most recent 10 percent of Earth's history, since about 385 million years ago. Once life got a foothold beyond the oceans, however, it spread rapidly. Within 200 million years, forests spread across the continents and the first amphibians evolved into dinosaurs. Mammals became dominant after the demise of the dinosaurs 65 million years ago. Only in the last 2 million years, that is, 0.05 percent of Earth's history, have humans appeared.

About the Author

Dr. Badruddin Khan teaches Chemistry in the University of Kashmir, Srinagar, India.

How will the universe end?

There are a few different poplular scientific theories out there right now...

The Big Crunch - Everything falls back in upon itself in a giant fire-ball.

The Big Freeze - Everything runs out of energy and universe-wide heat is down to absolute zero.

Big Rip - Not only is the universe accelerating outwards, its acceleration rate is increasing, and eventually gravity, and even strong and weak subatomic forces will not be strong enough to "keep it together" and everything will literally be torn apart by the ever acceleratingly accelerating expansion of space itself.

Fermion-Boson Theory - The universe goes through a heat death, but then certain chemical condensates are formed, and eventually cause another Big Bang(s) which may create a new, or many new, universes.

And I'm sure you have many more ideas...

Not a physicist, but the Big Crunch always made the most natural sense to me.

The other theories already accept the fact that the universe began in a singularity and is currently expanding. But what force could have been used to create that bang other than the universe collapsing on itself in the first place?

Freeze and Rip are quaint.. that would make us very special.

Thanks for mentioning the condensate theory... I've never heard of that before, and after a quick read through, I found it interesting. Again, it makes me wonder however, if it's like fireworks and one begets another, wouldn't the initial energy required to create the singularities eventually diminish?

How to install a Condensate Pump

admin posted at 2009-5-31 Category: home improvement