General Boiler System Understanding

Todd_22

You should use the AFM module which is an option on the Ultra Oil. This control can run DHW priority, mixing valve or injection pump, high temp setpoint and a system pump. I just was on a job that this control was installed and it was also being used to run two boilers. Pretty slick, they have the manual for download or order on www.weil-mclain.com
You will need some type of mixing device to get the differant temps. If you follow the manual it will give you the piping and wiring diagrams for whatever you need.

Rob_42

Boiler Basics

I would like to bet a little boiler 101 from you gurus.

I will be having a Ultra Boiler UO3 in my garage. It will need to satisfy 4 requirements.
1. Indirect Fired Hotwater Tank (spec @ 190F supply)
2. Garage Slab Loops (assuming 85 to 110F supply)
3. Hi-Velocity FanCoil for Main and 2nd Floor(spec 160F supply)
4. Hi-Velocity FanCoil for Basement (spec 110F supply)

The Garage would have a thermostat as would the 2nd floor (controling the main and second floor temp) and the basement would have its own thermostat.

How exactey does the boiler go about dealing with the 3 heating zones? Is it controlled via priority like the DHW? Also the temperature variation in supply is quite large should the DHW requiremetns be met and the garage is then wanting heat at almost half the temperature of the DHW.

Sorry if these are elementary questions, but I am reading these forums as much as possible to learn but still feel I am missing some basics.

Rob_42

AFM Control or other?

OK, would the AFM control (which is optional on the Ultra) be better than going with a Tekmar that I hear so many good things about?

Todd_22

AFM

Is actually made by Tekmar for Weil Mclain. It's printed right on the control.