New boiler cutting out on low water

Diar

My new WM 480 is short cycling on low water. It cycled once or twice after the radiators were pretty satisfied after it was originally installed, but after a few days the water got really cruddy and it is constantly cycling and struggling to get heat to the radiators.

The system has 1100 sq ft EDR radiation and some pretty big long mains ( couple hundred feet of mains total ) and a large distribution ( 5000 sq ft house ). The WM is probably firing at at 3.4 gph, which should generate 1250 sq ft steam. The mains have vent-rite 35s on them and there is a single four inch riser/header that feeds the two mains.

The water line when off is 2" below the top of the water gauge. It takes about 2-3 minutes to cut off on low water.

Anybody know the best / most direct way to fix this problem?

Charles G.

Short cycle

Sounds like a classic case of water surging. All the oil and crud in the repipe process is sitting as a film on the surface of the (cruddy)water. So now's the time to start skimming and flushing. Get out the manuals or better yet, call the techs back so they can finish the job.

Diar

I agree that the problem has gotten much worse since the crud. However, I'm not sure if its surging. The water line steadily sinks, with small bounces of about an inch. It needs to sit below the low water cutoff steadily for about 10 seconds before it cuts out.

Is that surging? I would figure that surging would cause large flucuations in water level, but this is a fairly steady drop in water.