Viessmann VITOPLEX 300 Type TX3A - Vitoradial 300-T, type VR3, 101 to 335 kW; 5.1 Product description; 5.2 Operating conditions with Vitotronic boiler control units and Therm-Control

5.1 Product description
Low temperature boiler with oil/gas condensing heat exchanger
Three-pass boiler with multi-layered convection heating surfaces
and downstream Inox-Radial spiral heat exchanger
For operation with a modulating boiler water temperature
Permissible flow temperature (= safety temperature) up to 110 ºC
Permissible operating pressure 4 bar
■ CE designation: CE-0035BU104
– according to the Efficiency Directive 92/42/EEC
– according to Gas Appliances Directive 2009/142/EC
■ Oil Unit condensing boiler with Vitoflame 100 pressure-jet oil burner
or gas condensing system with on-site burner.
■ Standard seasonal efficiency [to DIN] for operation with fuel oil: 97
% (H
s
)/103 % (H
i
).
■ Inox-Radial heat exchanger for condensing hot gases, matched to
the compact boiler.
■ Complete with heat exchanger pipework and pump, matched to the
respective boiler output.
■ Long burner runtimes and fewer cycle intervals, due to large water
content, protect the environment.
■ Economical and safe operation of heating systems through the dig-
ital Vitotronic control system with communication capability.
■ Integral Therm-Control start-up system for easy hydraulic connec-
tion – no shunt pump or return temperature raising facility are
required.
■ No low water indicator required, you save even more.
■ Compact design for easy transportation and low build height – impor-
tant for modernisation projects.
5.2 Operating conditions with Vitotronic boiler control units and Therm-Control
Requirements
Operation with burner load
≥ 60 %
< 60 %
1. Heating water flow rate None
2. Boiler return temperature (minimum value)
*1
None
*2
3. Low-end boiler water temperature – Oil operation 40 °C
– Gas operation 50 °C
– Oil operation 50 °C
– Gas operation 60 °C
4. Two-stage burner operation Stage 1; 60 % of rated output No minimum load required
5. Modulating burner operation Between 60 and 100 % of rated output No minimum load required
6. Reduced mode The boiler can be switched OFF if no heat is required.
7. Weekend setback As per reduced mode
Note
For water quality requirements, see page 44.
*1
For a corresponding sample application using the Therm-Control start-up system, see technical guide sample applications.
*2
No requirements only in conjunction with Therm-Control.
Vitoradial 300-T, type VR3, 101 to 335 kW
OIL/GAS BOILERS
VIESMANN
9
5822 426 GB
5