RECOMMENDED ABMA & ASME BOILER WATER LIMITS

DRUM OPERATING PRESSURE (psig) 0-300

301-450

451-600

601-750

751-900

901-1000

1001-1500

1501-2000

OTSG

0.2-1.0

0.2-1.0

0.2-1.0

0.1-0.5

0.1-0.5

0.1-0.5

0.1

0.1

0.05

STEAM TDS max (ppm)

BOILER WATER TDS max (ppm)

700-3500

600-3000

500-2500

200-1000

150-750

125-625

100

50

0.05

ALK. max (ppm)

350

300

250

200

150

100

Not specified

Not specified

n/a

15

10

8

3

2

1

1

n/a

n/a

1100-5400

900-4600

800-3800

300-1500

200-1200

200-1000

150

80

0.15-.25

150

90

40

30

20

8

2

1

0.02

TSS Max (ppm) Conductivit y max (µmho/cm) Silica max (ppm SiO2)

FEED-WATER (CONDENSATE & MAKEUP, AFTER DEAERATOR) Dissolved Oxygen (ppm O2)

0.007

0.007

0.007

0.007

0.007

0.007

0.007

0.007

Not sensitive

Total Iron (ppm Fe) Total Copper (ppm Cu) Total Hardness (ppm CaCO3)

0.1

0.05

0.03

0.025

0.02

0.02

0.01

0.01

0.01

0.05

0.025

0.02

0.02

0.015

0.01

0.01

0.01

0.002

0.3

0.3

0.2

0.2

0.1

0.05

None detected

None detected

None detected

8.3-10.0

8.3-10.0

8.3-10.0

8.3-10.0

8.3-10.0

8.8-9.6

8.8-9.6

8.8-9.6

1

1

0.5

0.5

0.5

0.2

0.2

0.2

1

1

0.5

0.5

0.5

0.2

0.2

0.2

pH @ 25º C Nonvolatile TOC (ppm C) Oily Matter (ppm)

MAKE-UP AT 0.5% BLOWDOWN TDS Silica (ppm SiO2)

11.4

9.8

8.1

6.5

4.9

3.3

0.5

0.3

0.75

0.45

0.2

0.15

0.1

0.04

0.01

0.005

MAKE-UP AT 1% BLOWDOWN TDS Silica (ppm SiO2)

22.8

19.5

16.3

13

9.8

6.5

1

0.7

1.5

0.9

0.4

0.3

0.2

0.08

0.02

0.01

MAKE-UP AT 2% BLOWDOWN TDS Silica (ppm SiO2)

45.5

39

32.5

26

19.5

13

2

1.3

3

1.8

0.8

0.6

0.4

0.16

0.04

0.02

MAKE-UP AT 3% BLOWDOWN TDS Silica (ppm SiO2)

68.3

58.5

48.8

39

29.3

19.5

3

2

4.5

2.7

1.2

0.9

0.6

0.24

0.06

0.03

None detected