help with a vaccuum steam system

jeffa

can anyone help me? I have a vaccuum steam system with 4" main headers. The radiators call for 1,856 sq ft. of steam, also has a webster boiler return trap. Can this be changed out with a conventional peerless oil steam boiler?

Jamie Hall

The short answer

is yes.  Once the steam gets out in the system, the source of the steam -- the make of the boiler and the fuel it is fired with -- is irrelevant.



Several cautions, though.  As always, the boiler -- whatever it is -- must be installed in accordance with the manufacturer's recommendations for piping -- or better.  Those recommendations are absolute minimums.  Don't skimp.



Second, be sure the new boiler is set up so that it has the same water level for normal operating as the old one.  This may mean setting it up on blocks; once in a long time it may mean lowering it (but that's rare).  If the water level is either significantly higher or lower, some very odd and undesirable things can (and probably will) happen.



Third, vacuum steam systems operate at very low pressure.  The new boiler will need a 0 to 16 ounce vapourstat as its primary control (you will need to have a regular pressurestat as a safety backup, too).



Fourth, while you are at it, check all your traps and vents for correct operation.



I'll probably think of more...

clammy

peerless oil steamer

Besides making sure you do not oversize your boiler also look into get a hi /low fire gun for the new boiler in conjuction with a vaporstat and you will be happy and help pervent short cycling and will use less fuel for sure  ,If you cannot replacate the original water line on the boiler then have a false water line install to avoid losing any water seals out in the systems piping ,end of the main and return seals when you lose them the headaches begin.If you installer cannot or does not want to installa hi /low fire gun and cannot wire it to work automatially find another installer .One last note is to follow the boiler manafactures near boiler piping recommendation and to exceed there header pipe sizes for the driest steam.I would be looking at a minuin of a 6 inch header and be sure to have at least 2 lwco on float and one electronic also if you are going to have a auto feeder installed be sure its a hydrolevel svt feeder it will recored how much water you take on very good investment with the 2 lwco to protect that investment.Make sure that any and all main vents and cross over traps are in proper operating condititons .Last but not least be sure the installer is familar with and has the tools to install a 6 inch header and is familar with vapor steam ,you should never need a condensate pump in a vapor system at least on most of the 100 year old system i have seen and worked on .Vapor system are the rolls royce  of steam systems and when it comes to replace make sure that who ever does the install is familar with vapor systems other wise you will have issues i know cause i have seen to many to mention and it is usually a big deal to straighten them out with alot of money getting wasted .You have come to the right place to get the real  answers about steam systems .Check out some of Dans books nothing better then a educated home owner in my opion .Peace and good luck clammy

nicholas bonham-carter

Webster system refit

As clammy has said, make sure that pressure is low! i have a 1,050,000 btu boiler with no auto/over-fill, all gravity. The air leaves the system at a back-pressure of 2 ounces, so make sure your air can get out as easily. Don't forget to get a good low-pressure gauge (gaugestore.com 0-15 ounce), so you know what th vaporstat is doing. You will love the comfort, economy, and silence when all is working as it should!--NBC