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Heat pump cylinders

uniSTOR cylinder range for heat pumps

  • Complete with three-way valve and adapter, making it easier and saving time on install.
  • Comes with unvented kits and expansion vessel
  • Inline front connections, reducing piping issues in smaller, more compact areas


Performance and reliability are what Vaillant are all about. That’s why our products have been expertly designed and engineered to work to their full potential together. Working in perfect harmony with the Vaillant range of heat pumps, the uniSTOR cylinder range uses state of the art insulation to give the ultimate efficiency.

What's in the range?

  • 150 litre pre-plumbed slimline heat pump cylinder
  • 200 litre pre-plumbed heat pump cylinder
  • 250 litre pre-plumbed heat pump cylinder
  • 300 litre pre-plumbed heat pump cylinder
  • 150 litre standard heat pump cylinder
  • 200 litre standard heat pump cylinder
  • 250 litre standard heat pump cylinder
  • 300 litre standard heat pump cylinder

500 litre and 800 litre cylinders available. For more information please contact your local sales representative.



Heat pump cylindersUnit 150 litre pre-plumbed uniSTOR200 litre pre-plumbed uniSTOR250 litre pre-plumbed uniSTOR300 litre pre-plumbed uniSTOR150 litre standard uniSTOR200 litre standard uniSTOR250 litre standard uniSTOR300 litre standard uniSTOR
Article number  00202371290020237130002023713100202371320020235271002023527200202352730020235274
Total tank capacity l149.2199249.8 298.7 149.2199249.8 298.7
Actual capacity (with coil)l143.05191.4240.3289.2289.2191.4240.3289.2
Hot water capacity / draw off (EN12897)l135183.2186.3230.9133183.2211208
Outer diameter with insulationmm430595595595595595595595
Net weight empty cylinderkg54.55873.380.638466167.63
Weight of filled cylinde kg193.97248.7309.6354.09181.8 237.4 301.3356.83
Standby losses kWh/24h1.64 1.22 1.41 1.59 1.0 1.22 1.41 1.59
ErP label bandCBBBBBBB
Reheat time
Heat echanger power / coil rating kW 20.6 26.0 40.7 50.5 20.8 26.0 40.7 50.5
Primary flow rate l/h900900900900900900900900
Maximum operating DHW temperature °C 8585858585858585
Maximum operating heat circuit temperature °C 9595959595959595
Primary heat exchanger
flow and return connection
inch¾ “¾ “¾ “¾ “¾ “¾ “¾ “¾ “
Cold and hot water connection inch¾ “¾ “¾ “¾ “¾ “¾ “¾ “¾ “
Temperature sensor sleeve diametermm88888888
Quantity of temperature sensor tubes 11111111
Immersion heater boss diameterinch1 ¼“ 1 ¼“ 1 ¼“ 1 ¼“ 1 ¼“ 1 ¼“ 1 ¼“ 1 ¼“
Size supplied expansion vessell1218252512182525

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