One pipe steam system

Frank Dobbs

A heat exchanger replaced several radiators on the ground floor of my brownstone when it was a restaurant. Heat exchanger was removed now that space is becoming residential. After heat exchanger was removed, boiler started short cycling badly. I guess the boiler was now very oversized.
There are radiators with thermostatic valves on the second and third floors.
There is no insulation on basement pipes, and the basement gets very hot. Pipes need insulation.
There is some knocking and gurgling when steam comes up.
As far as I can see, there are no main vents.

Weil-McClean EG75, 3 yrs old, DOE 240,000 MBH gross output. Heat loss for house is probably 140,000 BTUH.
According to the manual, boiler cannot be adapted for tankless or storage heater use.
There is a separate gas HW heater.

Questions:
1. Should I install sufficient steam radiation on the 1st floor to equal the expected heat loss? I’ve learned from this site that boilers should be sized to fit existing radiation. But this is the opposite question. I have radiation missing. Should I add radiation to counter the heat loss of the space, or should I add enough radiation to balance the output plus pick-up of the boiler?

2. Once I install sufficient radiation, if the boiler is oversized, is it possible to down-fire it and should I?

3. It would help in balancing the input/output of the system if I could get HW out of it, at least in winter. Is there any way to do so given its design limitations?

4. Are there any knowledgeable steam contractors who service downtown NYC. My GC in this renovation doesn't know any.

Steamhead

Frank, I would

install enough radiation to take care of the heat loss. You should be able to find lots of good used radiators in your area.

You might be able to run an indirect heater off that boiler, but you may need a heat exchanger to isolate the coil in the indirect from the boiler water, which can be rather hard on an indirect coil.

Down-firing the boiler may or may not be a good idea. A lot will depend on what the final load is and how much it is below the boiler's rated capacity.

Try the Find a Contractor page of this site to locate a contractor near you. I know of several up that way who know steam.

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

Unknown

One pipe steam

When the heat exchagers were removed some one might haave screwed up the return piping.

What you call short cycling may not be short cycling. If the boiler shuts down on the pressure controll setting or shuts down via "T" stat that is not short cycling. When limit switches are satisfied normally you are O.K.

If the boiler does not run out of water you can down size the fire rate up to 40% with out problems.

This can ge accomplished by closing off several gas jets to the burner.

If this what is needed stagger the shut down of the gas jets.

Jake