View Full Version : prioritizing zones

02-09-2007, 03:23 PM
I have three zones in my house, 2 zones are wirsbo and the upstairs is baseboard heat. The baseboard has a hard time recovering during cold weather. The boiler discharge temp only gets around 120 deg. The boiler temp is set at 200 deg. Any Ideas? I was thinking maybe I should prioritize the baseboard. Isn't the discharge temp suppose to match the boiler setpoint?

Open to ideas,


02-09-2007, 04:14 PM
Do you mean that you have radiant heat (in-floor) in two zones and baseboard in the other?

If so, it sounds like they used a mixing valve to set the output to 120-degrees for the in-floor stuff. If you are using zone valves and not separate circulators, it may be harder to get the boiler output at max temp to the baseboard. They did you a disservice plumbing it that way.

Basically, you need the baseboard stuff to come off of the boiler output prior to the mixing valve so it will get the right design temperature.

My guess is that your boiler is getting to around 200, but the mixed output is being fed to all zones, limited to the 120-degrees (whichis a common limit to in-floor heating loops).

Wirsbo tubing could be used to supply the baseboard - just using the brand name does not describe what you have.