Phantom Steam Thief

Jeff_44

I have a one-pipe system that until recently has been running like a top. Now, when the system runs, one (sometimes two) random rads don't get heat (or very little). It's anyone's guess which rad will the the cold one. I have lots of venting on the mains (three gortons and two hoffmans). There are three large rads that are close to the boiler that demand lots of steam so I have their respective vents set low. The EDR load is 287 and the new boiler (six years old) is rated at 283. Any help would be appreciated.



Thanks

nicholas bonham-carter

phantom thief

has your pressure changed? you will probably not be able to tell much with the original 0-30 psi, but if you had a good 0-2 psi low pressure gauge, you could get a sign that maybe the pigtail was clogged, and allowing the pressure to shoot up.

when this happens, some air vents, either main or radiator will not allow the air out. prolonged exposure to over-pressure will make them into paperweights.--nbc

Dave in QCA

Check the firing rate

Is this a gas or oil burner?  If gas, clock the meter for a full one minute period, during which no other gas appliances are running, and see if you are burning the correct amount of gas. 

Regarding your radiator vents, what type are you using, and what are the settings that you are using?  Are you sure that your main vents are working correctly?

Jeff_44

Thanks

I checked the pig tail and it was clogged - I cleaned it and will see what effect this has.



As far as venting on the mains, things have been working so well that I haven't really kept track of them but I followed Steamhead's advise several years ago - one main as a gorton #2 and the other has two Hoffmann's combined with a Gorton #2. On the radiators, we had maid - o - mist but have been swapping these out with Varivalve adjustable vents.

Jeff_44

After more checking

I learned that the main with one Gorton got hot/steam with in a couple of minutes from the boiler. The other main (which is about 10 feet longer and has three vents) didn't get hot for about five - seven minutes after the first main got hot. I wonder why this would be so different? AND...this is a gas burning boiler.

Steve_175

Check the Mains

to see that they are pitched a bit, level and the condensate is going to slow down that steam. Also check the vents on that slow main. Take them off and see if they are clogged

Your shorter main could have rad vents that are to aggressive. As I have read here vari vents even turned down are quite fast venting.

jpf321

is your boiler sooted?

perhaps during the season, a poorly tuned combustion system lead to a sooted boiler .. perhaps you need the chamber cleaned .. best left to a pro.