Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Buderus BFU

Alan R. Mercurio_3
Alan R. Mercurio_3 Member Posts: 1,624
in THE MAIN WALL
Hi Andy, I have installed a few of these in the past all with good results. here's some data I shared with others on my web site a few months back. I hope you find it useful. If I can be of further assitance don't hesitate to contact me. Please keep in mind if I don't get right back to you today it's cuase I'm hitting the road in about 5 min. Heading for NY to provide some training to our fellow technicians.

<b>For Multi-Zone Space heating (constant circulation) / Indirect DHW Heating</b>

Space heating operation:

Boiler temperature is maintained on the select heating curve (REF Temp and Offset) and inputs from the outdoor sensor (FA), Boiler sensor (FK) and Room Sensor (BF). This application requires a Multi-Zone relay of your choice. The 120v output from terminal 63 (PH-HK1) in your Buderus control will energize the relay. However, the PH-HK1 is limited to a 5 amp maximum load. Therefore, multi-pump applications require an additional source of 120v power to the pupm relay. Generally the #63 terminal will be wired to the ZC terminal on the relay panel, however relay circuitry can vary.

The constant circulation pump (P1) should run continuously and all the additional pumps shall be energized by their individual thermostats. Keep in mind it is important that the power to the pump relay and the constant circulation pump shall interrupted when the following conditions are occurring.

1) DHW Priority is calling.

2) Condensate protection is activated.

3) The outdoor temperature exceeds the WWSD set point.

4) Initial part of setback period is taking place

This application requires a room sensor for constant circulation. And the end switch (X1-X2) on a multi-zone relay panel is not used.


Your friend in the industry,<BR>Alan R. Mercurio<BR><BR><a href="http://oiltechtalk.com">Oil Tech Talk</a>

There was an error rendering this rich post.

Comments

  • AKO
    AKO Member Posts: 34
    Buderus and BFU Sensor

    Looking to install a 115/28 with zone valves and an indirect DHW loop, and I have a couple of questions about the BFU indoor sensor.

    First, does the constant flow heating pump run when there is a call for recharging the DHW tank? The Buderus brochure makes it sound like the zone with the BFU sensor will always get flow when the boiler operates.

    Second, have people found that the BFU room sensor works well? Any problems?
This discussion has been closed.

Categories