cold radiator

willy46

I recently replaced my old Utica one pipe Steam Boiler with a Burnham Mega Steam Boiler. It works great but two radiators one in the breezeway and one in the garage which are on the kitchen, Dining room and living room loop do not get hot any more. I thought it was from a rust sedement clog in their common supply pipe so I snaked out. It was clean. Then I thought I needed a larger air relief so I installed a number 1 on the radiator in the garage. Nothing. So I took it off leaving the radiator open and turned the system on. A slight amount of air came out and I could hear the system running but no steam. The Burnham cycles every 12 minutes to check the low water limit and the old boiler just ran until the thermostat shut it off. Could this be the reason? If so can I change that setting? If I change that setting will that effect the efficiency of the system which I don't want to do because I'm going through $750.00 worth of fuel oil every month for a 1200 sq. foot home thats been heavily insulated and has new insulated glass windows. Your ideas will be appreciated Thanks.

Robert_25

Are you sure it is the LWCO cycling?

"The Burnham cycles every 12 minutes to check the low water limit and the old boiler just ran until the thermostat shut it off."



I'm no steam expert, but that sure doesn't sound right. How did you determine the LWCO is causing the burner to stop? Are you sure it isn't due to something else, such as the Pressuretrol?

willy46

cold radiator

When the boiler was first installed I thought the same thing so I called Tech support at Burnham they assured me that the cycling is the way the system is designed to operate.

Paul48

Set Point

If you are using setpoint control and maintaining a pressure in the system, you will have problems with condensate building up in the radiators.The vents are suppose to act as a vacuum break when the system goes to zero pressure.What's the boiler pressure set to? This is what it actually does...

The Hydrolevel CG450 low water cut-off will shut down the burner for 90 seconds every 10 minutes of firing time to allow water level to stabilize. If the water level is too low the burner will not be allowed to restart

ChrisJ

cycling

I'm assuming your boiler has a cyclegaurd on it.  Most steam guys seem to hate these LWCO due to exactly what you are seeing.  The cycleguard stops the boiler to check for foaming I believe.



You will get more answers if you post this in the strictly steam section.  We will need to know total EDR of your radiators as well as the boiler size.

willy46

pressure set

The Honeywell Pressuretrol is set for Diff @.5 & Main @ 2 the boiler is Model # MST 396 and is rated at 95 mbh