part one pipe counterflow?

ssmh

On a gravity one pipe sytem, is it possible to have partial counterflow and standard gravity near boiler? Presently this is no real hartford loop.All return piping near boiler is below water line without tee in drop off header.This is a 175K system. Also the header is piped with 1 outlet going up into the side of a vertical tee on the main and the the other outlet comes horizontally and the upward into the bottom of aforementioned tee. Note main vent is located on what I would call the normal part of system near the boiler and before the portion that is counterflow. Should I change header and add hartford loop when replacing this boiler?

ssmh

Pictures

Here are a few pictures that may help

Paul Fredricks_3

Yuck

This piping looks all wrong to me. Hard to tell from the pictures, but if the returns are below water line you have to have a Hartford Loop.

ssmh

pictures

When looking at picture with toolbox, Boiler is in room directly behind. Large supply pipe comes thru, drops condensate at t , continues to feed garage heater. Large pipe continues on to feed second floor radiators with no condensate return pipe. Vent at radiators and main vent above that toolbox

Rod

Piping needs to be Changed

Hi-  Yes, it is possible to have a counterflow steam main and also a "standard" parallel steam main. 

The present near boiler piping needs to be redone. There really is no header and no Hartford Loop.  Since you are replacing the boiler, there should be a manufacturer's installation manual with diagrams showing how the boiler should be piped. These instructions need to be carefully followed. 

You might also take some more pictures of the boiler from a farther back position so we can see all the piping including the steam mains especially where the counterflow joins. (We can blow the pictures up if we need more detail.) Take the pictures from all sides of the boiler.



Edit-  Since the picture wouldn't load and you supplied more info I'll add more in here.

There should be a main vent at the top end of the counterflow main. (Actually set back from the end 15 inches if possible of avoid any water hammer) This vent  would speed up the distribution of steam to those radiators by taking the job of venting the main of the radiator vents.



The present vent, while it might help evacuate the main is more for the operation of hanging radiator I would think.

- Rod

ssmh

pictures

your edited pictures are blank on my post. boiler is behind toolbox and steam would be flowing in the direction where the picture was taken from. Note all radiators are on second floor.

Paul Fredricks_3

Us

We had a mixed system a few months ago. Banged like crazy when we were done. Found that we needed a drip just before the counterflow hit the header. Made all the difference in the world.

Rod

Counterflow drip

Here's a great example of a drip on a counterflow main. It leads straight down to the wet return. This well designed counter flow installation was done was done by Steve Gronski.

Note the nice header and 45 degree riser leads off the header. Excellent Work!