ARMSTRONG Astro 2 3-speed circulator models
Motor data
model | electrical input | speed | full load
amp draw (a) |
nominal
power (w) |
astro 210ci/ss |
115v, 60hz Single phase |
3 | 1.72 |
200 |
2 | 1.50 | |||
1 | 1.06 | |||
Astro 220ssu |
3 | 0.29 |
33 |
|
2 | 0.27 | |||
1 | 0.20 | |||
astro 225ssu |
3 | 0.69 |
83 |
|
2 | 0.55 | |||
1 | 0.43 | |||
astro 230ss/ ci/ci-r | 3 | 0.81 |
97 |
|
2 | 0.58 | |||
1 | 0.45 | |||
Astro 250ss/ ci/ci-r | 3 | 0.98 |
117 |
|
2 | 0.79 | |||
1 | 0.65 | |||
Astro 280ci/ss |
3 | 1.90 |
218 |
|
2 | 1.80 | |||
1 | 1.50 | |||
astro 290ci/ss |
3 | 1.90 |
218 |
|
2 | 1.60 | |||
1 | 1.40 | |||
astro 280ci/ss 230v |
230v,60hz Single phase |
3 | 0.90 |
210 |
2 | 0.86 | |||
1 | 0.80 | |||
Astro 286ci/ss | 1 | 1.60 | 375 |
Technical data
- Max. fluid temperature: 185°f/85°c (Astro 286 up to 1.35a) 50°f/65°c (Astro 286 over 1.35a)230°f/110°c (all others)
- Max. working pressure: 150 psi / 1034 kPa Certification: ETL listed for the US and Canada (conforms to ul std.778 certified to CSA std. c22.2 no.108-01) NSF 372 (for stainless steel models)
Since water conditions can vary with geographical location (i.e. amount and type of dissolved solids) it is recommended that the operating temperature o the fluid for open (potable) systems be kept as low as possible (i.e. below 150°f or 65°c) to avoid precipitation of calcium.
Materials of construction
Pump body:
- Cast iron (closed system)
- Stainless steel** (open system)
Impeller: Noryl
Shaft: Ceramic
Bearings: Ceramic
Gasket: EPDM
Certified <0.25 weighted average percent lead (NSF 372) and complies with California Health and Safety code section 116875 (commonly known as ab1953).

Dimensions and weights
stainless steel* | a | b | c | d | e | f | connection type & size | weight | |||||
Astro 220ssu** | 6.00 (152) | 5.00 (127) | 4.00 (102) | — | 3.10 (79) | — | Union – 1¼” npsm | 6.5 (2.9) | |||||
Astro 225ssu** | 6.00 (152) | 5.00 (127) | 4.00 (102) | — | 3.10 (79) | — | Union – 1¼” npsm | 6.5 (2.9) | |||||
Astro 230ss** | 6.38 (162) | 6.00 (150) | 4.00 (102) | 4.00 (102) | 3.10 (79) | 3.25 (80) | Flange – (2) ½” dia. bolt holes | 8.0 (3.6) | |||||
Astro 250ss** | 6.38 (162) | 6.00 (150) | 4.00 (102) | 4.00 (102) | 3.10 (79) | 3.25 (80) | Flange – (2) ½” dia. bolt holes | 8.0 (3.6) | |||||
Astro 210ss** | 6.50 (165) | 7.25 (184) | 4.87 (124) | 4.00 (102) | 3.60 (91) | 3.13 (80) | Flange – (2) ½” dia. bolt holes | 10.1 (4.6) | |||||
Astro 280ss (230v)** | 6.50 (165) | 6.75 (171) | 4.87 (124) | 4.00 (102) | 3.60 (91) | 3.13 (80) | Flange – (2) ½” dia. bolt holes | 10.1 (4.6) | |||||
Astro 286ss** | 6.50 (165) | 6.38 (162) | 4.87 (124) | 4.00 (102) | 3.60 (91) | 3.13 (80) | Flange – (2) ½” dia. bolt holes | 10.1 (4.6) | |||||
Astro 290ss** | 8.50 (216) | 6.65 (169) | 5.20 (132) | 4.00 (102) | 3.60 (91) | 3.45 (88) | Flange – (2) ½” dia. bolt holes | 13.2 (6.0) | |||||
cast iron | a | b | c | d | e | f | connection type & size | weight | |||||
Astro 230ci** | 6.38 (162) | 6.00 (150) | 4.00 (102) | 4.00 (102) | 3.10 (79) | 3.25 (80) | Flange – (2) ½” dia. bolt holes | 8.0 (3.6) | |||||
Astro 230ci-r** | 6.38 (162) | 5.63 (137) | 4.00 (102) | 4.00 (102) | 3.10 (79) | 3.25 (80) | Flange – (2) ½” dia. bolt holes | 8.0 (3.6) | |||||
Astro 250ci** | 6.38 (162) | 6.00 (150) | 4.00 (102) | 4.00 (102) | 3.10 (79) | 3.25 (80) | Flange – (2) ½” dia. bolt holes | 8.0 (3.6) | |||||
Astro 250ci-r** | 6.38 (162) | 5.63 (137) | 4.00 (102) | 4.00 (102) | 3.10 (79) | 3.25 (80) | Flange – (2) ½” dia. bolt holes | 8.0 (3.6) | |||||
Astro 210ci** | 6.50 (165) | 7.25 (184) | 4.87 (124) | 4.00 (102) | 3.60 (91) | 3.13 (80) | Flange – (2) ½” dia. bolt holes | 10.1 (4.6) | |||||
Astro 280ci (230v)** | 6.50 (165) | 6.38 (162) | 4.87 (124) | 4.00 (102) | 3.60 (91) | 3.13 (80) | Flange – (2) ½” dia. bolt holes | 10.1 (4.6) | |||||
Astro 286ci** | 6.50 (165) | 6.38 (162) | 4.87 (124) | 4.00 (102) | 3.60 (91) | 3.13 (80) | Flange – (2) ½” dia. bolt holes | 10.1 (4.6) | |||||
Astro 290ci** | 8.50 (216) | 6.65 (169) | 5.20 (132) | 4.00 (102) | 3.60 (91) | 3.45 (88) | Flange – (2) ½” dia. bolt holes | 13.2 (6.0) |
note: All dimensions are in inches (mm) and weights in lbs (kg).
- Certified <0.25 weighted average percent lead and complies with California Health and Safety Code Section 116875 (commonly known as ab 1953).
- Removable check valve installed at the pump outlet.
Cross-reference table 

note: 1 Dimension and connection may vary.
- Flange orientation may vary.
- Supply voltage may vary.
- Connection with ½” sweat adaptor(s). 5 Connection with ¾” sweat adaptor(s).
- S1 Speed 1.
- S2 Speed 2.
- S3 Speed 3.
Performance curves
Astro 225ssu
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Armstrong fluid technology was established 1934
Documents / Resources
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ARMSTRONG Astro 2 3-speed circulator models [pdf] User Manual Astro 2, circulator, 3-speed circulator |