My house has a 5 zone hydronic heating system. One of the zones is slow to warm up when I set the thermostat up, and never gets up to temperature when the outside temp is below 20F. I have insulated the supply and return lines to the zone and bled the lines to remove all air. I think that the problem is just too little radiator for the heat loss.
Is there a straight forward way of calculating baseboard radiation required for a room?
P.S. House was built in 1989; this is our first winter in the home, so don't know if this is a new problem, but suspect not.