Selecting new Gas steam Boiler

MikeMens

Hello,

I am replacing my old Bryant 450K btu input natural gas steam boiler for my 790-800 sq ft steam system with 315K or 350K btu input unit. I have been told by factory reps and contractors that 315K would do it but sice I have 3" supply lines AI should consider upsizing to 350K. I am looking at the Burnhma KIN10 or KIN11-LNI-LE2 or the EGH-95 from Weil McClain or Weil McClain 3-80 with Carlin Burner Any comments as to which is the better boiler or suggestions as to other makes/models to look at? My radiator inventory is attached.

Your input is appreciated;

KC_Jones

First the supply pipe size shouldn't have anything to do with sizing the boiler. The boiler size already has extra pick up built in to deal with this. You will get varying opinions on which is better since different contractors have their favorites. Some will say your choice of the 3-80 is the best bet because the efficiency is better due to it being a wet based boiler AND a good burner tech can tune the input to very closely match your system. @Steamhead is a big fan of this type of system so maybe he will comment. Either way the IN11 is definitely oversized the IN10 would be plenty. The EGH-95 would technically be oversized and some would say you could probably get away with the EGH-85, but possibly even the EG-75. There has been much debate lately about pick up factors on this site. Without knowing much about the house or the heatloss etc. can't really intelligently comment about that though. If you went with the 95 a 2 stage gas valve would be a great addition. I have a feeling you will get many comments on this once more people see your post.

Steamhead

I was going to suggest the 3-80/Carlin power gas burner, but KC beat me to it.

The advantage of this setup is that it captures heat better than the usual atmospheric type of gas boiler. You have much better control of the combustion process since the heat-transfer surface surrounds the flame almost completely, and all the air going to the flame is adjusted at the burner's air gate.

The main disadvantage is that you can hear it running. It sounds like an oil burner. Also, we haven't seen 2-stage firing trickle down to boilers of this size, but that could change.

We installed one of these and the lady likes it so much she shows her boiler off to guests. Have a look:

http://forum.heatinghelp.com/discussion/148298/atmospheric-out-power-burner-in#latest

Dave0176

Ever think about two boilers and and modulating them. For that size I'd install two Weil McLain EG45s with two stage gas valves and modulate them.