Water hammer Pictures and a video

Trane System Information

Here is a link to a pdf file here in the Heating Help Library.  http://www.heatinghelp.com/files/articles/1392/26.pdf   Read the whole thing, it will be helpful to you, but especially, see pages 11 and 13.



The noisey pipe that drops from the steam to the return line behind your boiler, is part of the necessary piping for the Trane Direct Return Trap, located in you hallway.  In order for this device to work properly, it requires the check valves that are located in the line down by the floor and also property steam connections, etc.  The purpose of the direct return trap is to return condensate to the boiler when the boiler pressure is high enough that it would prevent it from returning by gravity alone.  Under low pressures, probably up to 1 PSI, the condensate will return by gravity alone.  1 PSI in the boiler will cause the condensate return to back up about 32 inches.  So, if your condensate lines are at least 32" above the boiler you are fine.



So, when this boiler was installed along with the condensate tank, the contracted did not understand or know what the Trane Direct Return trap was, or how it functioned.  He also overlooked that part of this setup is a steam connection down to the wet return, which he piped directly into a vented condenstate resceiver.  There is a about a 3" rise in the piping at the connection to the tank, but as soon as there is a few ounces of steam pressure it is going to be enough to push steam through that line and it will HAMMER like mad!  As you have observed.   Ha!



The installer also inserted a F&T trap out in the hallway in the drip from the steam main to the return line.  This is not needed either as long as the return trap is functioning correctly because it connects to the return piping after the check valve which prevents it from pressurising the return lines, but allows condensate dripping from the steam main to return back to the boiler, the wet return piping at this point being the same pressure as the boiler.



Also, the contractor installed a check valve in the Hartford loop, the wrong spot for that.



You need to get a good steam contractor, someone who understands this type of system, and remove the condensate pump and any other minor knuckle headed work, tie in the water feeder correctly, remove the F&T trap, perhaps install a vapor stat to provide very low pressure control, 8 ounces is plenty of pressure on this system.   You will love this vapor heat system when it is working correctly!!!

In Good Hands!

Well, regarding disclosure, it is likely that the previous owner thought that it was normal to clang and hammer. 



You will be in the hands of the best of the best with All Steamed Up, Frank (Steamhead) and Gordo!!



They may also be able to offer advice on your A/C projects and save some money.  In my experience, mini splits are one of the most expensive ways to go, and while they may be the best solution in a few places, they are pretty obstrusive in historic homes, as I am guessing you may have.



Other possibilities are a conventional system with the air handler in the attic and air supplies in the ceilings -- easy on the 2nd floor and possible on the first often by dropping through closets.   If the house layout does not cooperate for that, the mini-duct high velocity systems are also a good solution.  I.E. Spacepak or Unico.  The equipment is more expensive but installation can be less costly, resulting in a good value.



All depends on the layout of your house, and what spaces are available.



As far as heat, when you get this system straightened out, install a gas gun, you may be amazed just how economical and comfortable this system is.

A Good Plan Indeed!

Oh, That kind of Mini Split!  Very good indeed.  It sounds like you have done your homework, and in fact it is an approach that I may have to look into myself.  Future work may involve restoring the first two floors (6 apartments) back to the original single family configuration at the Best Mansion.  It's construction, all masonry walls with reinforced conrete floor decks, does not lend itself to and easy solution for AC.



Thank you for the idea!!!



Also, regarding your vapor system, those were originally designed with checks on the vents, so that the air could go out, but not re-enter.  Once the fire shut off and the steam condensed, it would pull a vacuum of 5-10" Mercury.  This effectly lowered the boiling temperature of the water and therefore the vapor continued for circulate at a moderated temparature for a while.  When the boiler restarts, boiling commences at a lower temperature and circulation is established VERY quickly because there is very little or no air to be expelled.  The Vapor-Vacuum systems were the cadillac of heating, having the best characteristics of hot water and the best characteristics of steam.



There were many systems, each with their own little peculiarity.  The big names were Dunham, Trane, Hoffman, and Moline, but there were probably 1-2 dozen of them, that mostly accomplished the same end. 



I'm in the middle of a boiler replacement project, and the system will be restored to vacuum operation when the work is done.