Hot water boiler WTC-OB series

fuel oilcondensing

Overview
Weishaupt oil-fired condensing boilers use heating oil efficiently and with reduced emissions to produce low-temperature heat. The Thermo Condens® WTC-OB range is suitable for modernising existing oil boilers or for new installations and covers output classes from around 18 to 45 kW (examples: 20, 25, 30, 35, 45 kW).

Energy savings
The WTC-OB consumes only 4 W in standby. Supplied as standard with a low-energy pump, it significantly lowers electrical consumption compared with conventional boilers.

Recommended fuel
Domestic heating oil F30 - PR NF XP M15-040, maximum viscosity 6 mm²/s at 20°C.

Product benefits
The WTC-OB range features a Weishaupt purflam® blue-flame two-stage burner. Available in multiple power ratings (20 to 45 kW) and compatible with a wide range of accessories, it can be adapted to existing hydraulic systems. Suitable for both new-build projects and renovation of existing installations.

Ease of use and robustness
Particularly quiet operation thanks to integrated silencers on flue gas and air intake. The aluminium-silicon alloy heat exchanger is corrosion-resistant and provides high thermal conductivity for economical operation. Control and configuration are managed by a remote control unit mounted on the boiler or in the heated space.

Table of models (selection)
Model | Burner min output Qc | Burner max output Qc | Fuels | Standard efficiency at 40/30 (LHV) | Standard efficiency at 40/30 (HHV) | Heating efficiency class | Energy label scale | Width | Depth | Height | Weight
WTC-OB 20-B H | 15.2 kW | 20.7 kW | Standard heating oil EL, desulphurised EL, EL A Bio 10, paraffinic oil, without ash-forming additives | 105.0 % | 99.1 % | A | A+++ - D | 680.0 mm | 730.0 mm | 1 181.5 mm | 142.000 kg
WTC-OB 25-B H | 15.2 kW | 25.2 kW | Standard heating oil EL, desulphurised EL, EL A Bio 10, paraffinic oil, without ash-forming additives | 105.0 % | 99.1 % | A | A+++ - D | 680.0 mm | 730.0 mm | 1 181.5 mm | 142.000 kg
WTC-OB 30-B H | 21.8 kW | 30.7 kW | Standard heating oil EL, desulphurised EL, EL A Bio 10, paraffinic oil, without ash-forming additives | 105.0 % | 99.1 % | A | A+++ - D | 680.0 mm | 730.0 mm | 1 181.5 mm | 142.000 kg
WTC-OB 35-B H | 25.4 kW | 34.7 kW | Standard heating oil EL, desulphurised EL, EL A Bio 10, paraffinic oil, without ash-forming additives | 105.0 % | 99.1 % | A | A+++ - D | 680.0 mm | 730.0 mm | 1 181.5 mm | 142.000 kg
WTC-OB 45-A H | 33.6 kW | 44.2 kW | Standard heating oil EL, desulphurised EL, EL A Bio 10, paraffinic oil, without ash-forming additives | 105.0 % | 99.1 % | A | A+++ - D | 680.0 mm | 730.0 mm | 1 181.5 mm | 147.000 kg

Technical specifications

• Brand: Weishaupt
• Series / model: Thermo Condens® WTC-OB
• Power range: approx. 18 to 45 kW (e.g. models 20, 25, 30, 35, 45 kW)
• Burner type: Weishaupt purflam® blue-flame, two-stage
• Standby electrical consumption: 4 W
• Pump: low-energy pump (standard)
• Compatible fuels: Standard heating oil EL, desulphurised EL, EL A Bio 10, paraffinic oil, without ash-forming additives; domestic fuel oil F30 (viscosity ≤ 6 mm²/s at 20°C)
• Standard efficiency at 40/30 (LHV): 105.0 %
• Standard efficiency at 40/30 (HHV): 99.1 %
• Heating efficiency class: A
• Energy label scale: A+++ - D
• Heat exchanger: aluminium/silicon alloy, corrosion-resistant
• Operation: quiet (integrated silencers)
• Control: remote control for operation and configuration (on boiler or in room)
• Typical dimensions (W x D x H): 680 mm x 730 mm x 1 181.5 mm
• Indicative weight: 142 kg (depending on model), 147 kg (higher-power models)
• Adaptability: wide range of accessories and possibility to combine with WIT hydraulic tower; compact hydraulic components (0.3 m²)