Detail
Combined Surface and Bottom Blowdown Control
VIRA D-BS6-T is a combined automatic blowdown system developed for steam boilers requiring both controlled surface blowdown and periodic bottom blowdown. By managing dissolved solids at the water surface and removing settled sludge from the boiler bottom, the system supports stable boiler-water quality, safe operation and efficient steam generation.
Temperature-Compensated Surface Blowdown
The surface blowdown section continuously monitors boiler-water conductivity and controls the discharge of concentrated boiler water when the configured conductivity limit is reached. Temperature compensation supports dependable conductivity measurement under changing boiler operating conditions. A high-conductivity alarm can also be configured to warn operators when boiler-water conductivity exceeds the permitted value.
Automatic Bottom Blowdown
The bottom blowdown section removes sediment and concentrated impurities that accumulate at the lowest point of the boiler. Adjustable blowdown intervals and valve operating times allow the bottom blowdown cycle to be adapted to boiler capacity, water-treatment conditions and operating requirements.
D-BK 5000-T Combined Blowdown Controller
The D-BS6-T uses a D-BK 5000-T controller configured specifically for combined surface and bottom blowdown operation. Although based on the same technical platform as the controller used in D-BS4 and D-BS4-T systems, this version includes activated combined-control options and expanded operating menus.
Its touchscreen is divided into two dedicated sections: one for surface blowdown information and one for bottom blowdown information. Operators can view conductivity, surface blowdown status, bottom blowdown cycle status, alarms and related settings from one interface. The expanded menu structure provides separate settings for both blowdown duties while keeping their operation coordinated. The controller operates with 24VDC supply and is available for DIN rail or control-panel mounting.
Conductivity Measurement Assembly
The system uses the BD 5600-T temperature-compensated conductivity probe together with the DG 5400 probe body. The probe can be manufactured in project-specific lengths. The DG 5400 is selected in dimensions compatible with the selected surface blowdown valve and helps ensure correct probe positioning and contact with boiler water.
BKV 5400 Surface Blowdown Valve
The surface blowdown section uses the BKV 5400 control valve. Pneumatic and electric actuator options are available. The valve is offered in DN20, DN25 and DN40 sizes with PN40 pressure class. Its WCB body, metal-to-metal sealing design and integrated sample outlet beneath the valve support reliable operation in steam boiler applications.
BKV 4000 Bottom Blowdown Valve
The bottom blowdown section uses the BKV 4000 valve, available in DN25, DN32, DN40 and DN50 sizes with PN40 pressure class. The valve is pneumatically actuated with spring return. A switch box and NAMUR solenoid valve are supplied as part of the valve set, enabling valve-position monitoring and reliable actuation.
Monitoring and Integration
The D-BS6-T supports 4–20 mA conductivity output and RS485 Modbus communication for integration into boiler control panels and plant monitoring systems. Combining two essential blowdown duties in one coordinated system helps simplify operation while supporting efficient boiler-water management.
| Controller | : | D-BK 5000-T |
| Supply Voltage | : | 24VDC |
| Functions | : | TDS Blowdown, Intermittent Blowdown, Conductivity Set, Cond. Hysteresis, High Cond. Alarm, Valve On-Off, Calibration |
| Inputs | : | Conductivity Probe Input, Ground, PT 100 , Blowdown Valves, Switch Box |
| Outputs | : | 1 Valve On-Off Relay, 1 Alarm Relay, 4-20 mA Cond. Level Info, RS485 Modbus |
| Display | : | Touch Screen |
| Max. Ambient Temp. | : | 55 °C |
| Enclosure | : | PC |
| Type | : | Panel and Dın Rail |
| IP Class | : | IP 40 |
| Probe | : | BD 5600-T |
| Connection and Size | : | Threaded - G 1/2''' BSPT (Optionel NPT) |
| Nominal Pressure | : | PN 40 |
| Length | : | 500 mm |
| Max. Operat. Press. | : | 32 Bar (g) |
| Max. Operat. Temp. | : | 239 °C |
| Max. Ambient Temp. | : | 75 °C |
| PT 100 Temperature Sensor Included | ||
| The length of the probe is fixed and cannot be adjusted after production. Therefore, the required length must be specified at the time of order. |
| Valve | : | BKV 5400 |
| Size | : | DN 20, 25, 40 |
| Actuator | : | Electric, Pneumatic (Optional) |
| Motor Type | : | On-Off, Spring to Close |
| Pressure Class | : | PN 40 |
| Body | : | WCB |
| Sealing | : | Metal to Metal |
| Supply | : | 220VAC, 24VDC (please ask) |
| Operat. Temp. | : | -10-+230 C |
| Valve | : | BKV 4000 |
| Size | : | DN 20, 25, 40, 50 |
| Actuator | : | Pneumatic |
| Motor Type | : | On-Off, Spring to Close |
| Pressure Class | : | PN 40 |
| Body | : | WCB |
| Supply | : | 220VAC, 24VDC (please ask) |
| Operat. Temp. | : | -10-+230 C |
| Structure | : | Reduced Bore |
| Type | : | DG 5400 |
| Nominal Pressure | : | PN 40 |
| Sizes | : | DN 20, DN 25, DN40 |
| Max. Operat. Temp. | : | 239 °C |
| Max. Operat. Press. | : | 32 Bar g |
| Body | : | Nodular Cast Iron, Carbon Steel |
