ATAG iSteel Unvented Cylinders
ATAG iSteel Unvented Cylinders
The iSteel unvented cylinders range from 90 to 300 litres. They work with ATAG iS system and iR regular boilers.


Key features and benefits
- Rapid heat up recovery
- Rated ‘B’ for energy efficiency
- Compliant with part ‘L’ of the building regulations – conservation of fuel and power
- A 25 year warranty
- A 2 year warranty on cylinder components
Specification
The table represents the technical information for the cylinder part number.
PART NUMBER | CY500090 | CY500120 | CY500150 | CY500180 | CY500210 | CY500250 | CY500300 |
CAPACITY (LTRS) | 90 | 120 | 150 | 180 | 210 | 250 | 300 |
HEIGHT(MM) | 760 | 940 | 1140 | 1320 | 1510 | 1720 | 1980 |
DIAMETER(MM) | 545 | 545 | 545 | 545 | 545 | 595 | 595 |
WEIGHT EMPTY(KG) | 23 | 27 | 31 | 35 | 39 | 48 | 55 |
WEIGHT FULL (KG) | 111 | 145 | 179 | 213 | 247 | 296 | 352 |
INDIRECT REHEAT (MINS) | 12 | 16 | 17 | 20 | 22 | 25 | 34 |
IMMERSION REHEAT (MINS) | 53 | 80 | 106 | 136 | 167 | 213 | 385 |
HEAT EXCHANGER (KW) | 16.46 | 16.46 | 18.55 | 18.55 | 18.55 | 22 | 22 |
STANDING LOSS (KWH/DAY) | 0.96 | 1.11 | 1.26 | 1.40 | 1.54 | 1.76 | 2.03 |
COLD INLET | 195 | 195 | 195 | 195 | 195 | 195 | 195 |
IMMERSION 1 | 345 | 345 | 340 | 340 | 365 | 365 | 365 |
IMMERSION 2 | – | – | – | – | – | 965 | 980 |
SEC. RETURN | – | – | – | – | 1160 | 1410 | 1605 |
T&P VALVE | 525 | 710 | 890 | 1085 | 1265 |

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