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DIY Jaga Dynamic Boost Hybrid (DBE/DBH)

(Updated: )

Contents

I have Jaga radiators in my home, which are of the type hot-water baseboard making them great low-thermal momentum, high power density radiators, especially compared to panel radiators. In this article I build my own temperature-controlled fans on top of these to increase the power and reduce heating lag even more. Cost is ~60€ per 70cm unit with 7 fans, compared to 300€ for Jaga’s version and only 3 fans for Speedcomfort’s version.

Bare Jaga radiator with DIY fan array end-result

Introduction

Jaga sells ready-made fan modules called DBH (Dynamic Boost Hybrid), which replaces the older DBE (Dynamic Boos Effect) modules. These come with a control and sensing unit, but are fairly expensive at ~300€ per meter. Alternatively there’s a company called Speedcomfort which make their own version, but they’re more aimed at panel radiators instead of the Jaga baseboard radiators, and only have 3 fans which means it’s louder or has less airflow.

Since I like the challenge and learning, I decided to make these myself, greatly inspired by the Gathering of Tweakers forum thread on this topic.

Requirements

TL;DR - instructions for the impatient

  1. Prepare aluminium frame
    1. Mark out fan holes with the fans in place (e.g. using a screw to scratch in the aluminium)
    2. Drill 5mm holes to mount the fans (needs to be somewhat precise)
    3. Saw out approximate fan blade area (to have unobstructed airflow)
    4. Drill holes in the side wall of the frame to fix the wires on
Marking out fan holes on aluminium frame

Marking out fan holes on aluminium frame

Drilling out fan holes & sawing out fan blade area for improved airflow

Drilling out fan holes & sawing out fan blade area for improved airflow

End result of two alumiunum frame with sawed out fan blade area

End result of two alumiunum frame with sawed out fan blade area

  1. Mount & connect the fans
    1. Mount the fans in the frame using supplied screws or M4 bolts
    2. Wrap the cable around the fan to prevent dangling
    3. Connect the cable to the essential molex fan plug splitter
    4. Fix the cables to the hole in the side-wall drilled previously
Mounting the fans in the frame

Mounting the fans in the frame

Connecting and fixing the cables

Connecting and fixing the cables

Close-up of cable management

Close-up of cable management

  1. Make the controller, connect power
    1. Take a ~15cm piece of aluminium profile to mount the step-down converter and power supply
    2. Mount the DC jack connector to connect the thermostat switch
    3. Use the switch to break the positive polarity from the power supply, such that the step-down converter is not connected to live power when not operating.
    4. N.B. I mounted the controller + power supply away from the radiator (because of space and splash risk), such that I have 2 double-polarity cables running from the control unit to the radiator: 1 is for the thermostat switch, the second is for the 12-V power.
Frame for controller and power supply

Frame for controller and power supply

(Logical) wiring diagram for power supply, switch, and step-down converter

(Logical) wiring diagram for power supply, switch, and step-down converter

Frame for controller and power supply

Frame for controller and power supply

  1. Make support structure & installing
    1. To reduce noise slightly, I made a spacer between the radiator and fan out of cardboard.
    2. Simply cut to shape using scissors.
    3. Place in between fans to minimize airflow interference.
Cut cardboard to shape, place in between radiator grill blades

Cut cardboard to shape, place in between radiator grill blades

Place in between fans.

Place in between fans.

Place in between fans.

Place in between fans.

  1. Connect & power-up
Fan array just before outer casing mounting.

Fan array just before outer casing mounting.

Fans are visible from the top, but barely noticable in daily life.

Fans are visible from the top, but barely noticable in daily life.

Final configuration. Towel not included.

Final configuration. Towel not included.

Hardware and design

This is most of the hardware required to make the DIY DBE fan arrays. Power supply not shown.

Most material used to make these fan rigs

Bill of Materials

For 2x 70 cm fan arrays, suitable for a 160cm Jaga radiator:

Total cost: 114€, plus shipping etc.

Fan throttling

There are different methods to control fan speed, e.g. using the fancy and optimal PWM, or using a blunt and simple voltage control. I settled for the latter for ease of use, as I can simple use a step-down converter (also called buck converter) to regulate my 12V input to anything from 0-12V.

Step-down requiremnets

Options:

Chose XL4015 because of high efficiency and display.

Fan requirement

Fans considered (see overview here:

I ordered each one of each, but did not notice too much of a difference in noise/airflow with an unscientific approach of listening by ear and feeling airflow with my hand. I therefore settled for the Arctic F9 fans for their low cost.

Temperature control

I settled for a simple on/off thermostat which can switch my 12V input voltage. A more fancy control using temperature sensors, ESP8266, Wifi, MQTT etc. are all possible, which might provide slightly better performance, but I want my radiator to work when I turn the knob 🤓

Options found:

I chose the Speedcomfort for my setup.

Power supply

Requirements:

I had spare power supplies lying around, but else I would go for something from seasonic like this 60W Seasonic unit. Unfortunately 3A @ 12V is slighly beyond the capabilities of adapter-type power supplies, so you get these brick-type supplies instead. Better safe than sorry.

Construction considerations

Fan frame

I used aluminium profiles (20x20x2 mm^3) to hold the fans. This is light-weight yet sturdy, and relatively easy to saw/cut into shape yourself. For wider Jaga models (e.g. T20), you could use thin multiplex wood (e.g. 3.6mm) instead, which is slightly easier to saw/handle.

Optimal thermocouple positioning

I tested a few locations to put the thermocouple, and in the end I compromised between optimal position (=fastest response) and accessibility. I mounted it to the

Timing:

#heating #home improvement #diy