I have a Well McClain water boiler that feeds a former steam system. The main part of my house consists of 8 radiators(4 per floor). The first floor piping of 3 of 4 radiators iron pipe starting at 2.5" and reduces to 1.5" eventually. The 4th radiator has new 1-1/4" copper and is branched right of the 2.5" pipe at the exit of the boiler. This 4th radiator heats up extremely quick and stays very hot during a furnace run. The upstairs radiators are feed by 1" piping(some copper others iron). They are very slow to heat up and never seem to get as hot as first floor. My question on all this system is I notice when the furnace runs(not often yet) and heat is called for, the pump clicks on sends a plug of water for about 1-2 mins and shut off as the temp drops on boiler. It builds up temp again and then sends another plug of water. Is this normal operation? The plugs run longer as the system heats up. It just seems like the system runs a long time(45mins or so) although only once per morning.

Finally getting to finishing a zone for my finished basement. Zone is all plumbed and has benn sitting capped off. Only plannig one bleeder at the high point of the zone. Main question is that will the convection work properly. The zone will be about 140 feet with 36 feet of baseboards. At the end of the zone when the water hits the return it will be flowing up. Will the zone require any extra pump?