No heat on last rads

oldbobcat

I have a steam boiler that has two 3 inch feeds that each go half way around the house pitching down the whole way. Only 1 pipe rises to each rad. At the end of each run there is a vent then a 1 1/2 return that goes down then back to the boiler. There is 2 lbs of pressure in the system. The system works flawless with one exception, all the rads heat at at the same time except the last one on each run, by the time it starts to get heat the boiler shuts off and we end up with two cold rooms. It will get hot if the boiler runs for long periods in cold weather.

There is no clanking banging or excess oil use. Anyone have any ideas?

Thanks

ALIGA

Have you tried removing the vents

On the last two rads?



You may need vents that vent faster.

ALIGA

Have you tried removing the vents

On the last two rads?



You may need vents that vent faster.

oldbobcat

No heat

I did on the last one and could feel a little air but still took much to long for steam to arrive.

Rod

No Heat in Last Rads

Hi- I would help us if you could post a picture and any information /markings of the vents at the end of each run. Also what make  /model vents do you have on your radiators?

- Rod

Steamhead

How long

are those 3-inch mains, and what vents are on them?