Vitotrans 353

Freshwater module

Freshwater module for DHW heating using the instantaneous water heating principle, draw-off rate up to 68 l/min depending on model

High draw-off rate
Instantaneous water heating principle
For wall or cylinder mounting
Compact design

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High draw-off rate

This makes it versatile, e.g. in detached/two-family houses, sports facilities, care homes

Instantaneous water heating principle

Fresh DHW is always available, no storage is required

Quick and easy wall or cylinder mounting

Thanks to pre-installed module – control unit and high efficiency circulation pump are integrated and connected

Compact design

This makes it easy to integrate into the existing heating system with heating water buffer cylinder

Can be linked in cascade

With no additional external control unit (types PBMA, PBMA-S, PBLA and PBLA-S)

Low flow temperature required

Thus ideal for integration in low temperature heating systems with solar thermal systems

Vitotrans 353 freshwater modules

Freshwater modules offer convenient and hygienic DHW heating according to the instantaneous water heating principle. Unlike conventional DHW cylinders, the water is not used for storing thermal energy, but instead is only heated when required, by means of a powerful plate heat exchanger.

The energy for this DHW heating is drawn from a heating water buffer cylinder, which can be heated by a wide range of systems – by solar thermal systems, solid fuel boilers, conventional oil/gas boilers, heat pumps or other systems.

Hygienic DHW heating using the instantaneous water heating principle

The Vitotrans 353 can ensure a constant outlet temperature at the hot water tap at varying draw-off rates. High efficiency circulation pumps of the latest generation are speed-controlled by an integral control unit so that the heating water flow rate is always at the optimum level for the current draw-off rate.

The five Vitotrans 353 types offer perfect convenience, optimum hygiene and forward-looking energy saving operation.

Product series for wall mounting

  • Type PBSA, 25 l/min draw-off rate
  • Type PBMA/PBMA-S, 48 l/min draw-off rate
  • Type PBLA/PBLA-S, 68 l/min draw-off rate

DHW circulation series for installation on the heating water buffer cylinder

  • Type PZSA, 25 l/min draw-off rate
  • Type PZMA, PZMA-S, 48 l/min draw-off rate


New to the proven Vitotrans 353 is a version with a nickel-soldered plate heat exchanger. This alternative to the copper version, which is still available, can be installed wherever there is a susceptibility to copper corrosion due to the water quality.

Freshwater modules

Freshwater modules for wall mounting

Freshwater modules for wall mounting with types PBSA (25 l/min draw-off rate), PBMA/PBMA-S (48 l/min draw-off rate) and PBLA/PBLA-S (68 l/min draw-off rate), are delivered without DHW circulation pump and can be retrofitted with a DHW circulation set (accessory) inside the thermal insulation. Furthermore, it is possible to use a return distribution set (accessory) via a 3-way diverter valve installed near the heating water buffer cylinder.

In order to increase the draw-off rate, it is possible to interconnect up to four identical modules of type PBMA/PBMA-S and PBLA/PBLA-S to form a cascade. No additional control unit is required, as the integral control units communicate with each other via a BUS cable.

Vitotrans 353 freshwater modules for wall mounting, types PBSA/PBMA/PBMA-S (left) and PBLA/PBLA-S (right)

Freshwater modules in DHW circulation series

Further models are available in the DHW circulation series for installation on the heating water buffer cylinder. Models PZSA (25 l/min draw-off rate) and PZMA/PZMA-S (48 l/min draw-off rate) are delivered from the factory with an installed DHW circulation set as well as a return distribution set for quick and simple cylinder mounting.

Freshwater modules in DHW circulation versions can be combined with the following Vitocell heating water buffer cylinders:

Vitotrans 353 freshwater modules of the DHW circulation series, types PZSA and PZMA/PZMA-S, installed on the Vitocell 100-E, 120-E, 140-E and 160-E heating water buffer cylinders

Product details

Draw-off rate*
  • Type PBSA: up to 25 l/min
  • Type PBMA: up to 48 l/min
  • Type PBMA-S: up to 48 l/min
  • Type PBLA: up to 68 l/min
  • Type PBLA-S: up to 68 l/min

    *according to SPF test procedure (test method for freshwater modules according to the Institute for Solar Technology in Switzerland)
Product cross-section Vitotrans 353 type PBLA/PBLA-S