False Water Line or Gifford Loop needed?

MikeyB

When you have dry returns that were probably wet returns at one time,would you need to put them back under water to make them wet again? even if you do not presently have any problems with the system (water hammer, water leaving the boiler, etc)? The pictures attached show a boiler that has been in service for over 35 years and it is sized well to the system , and you can see the 2 return lines circled in the picture and the other picture shows where they drop to the floor, the boiler will most likely be replaced in the near future and was curious what you thought of installing a FWL or a Gifford loop (in place of the Hartford Loop) when the system is replaced? Thanks guys

gerry gill

yes, put in a

false water line, or put the boiler up on blocks to submerge the wet returns.

MikeyB

FWL

Thanks Gerry, what do you think about joining the 2 dry returns together right at the point where they turn down to the floor and run one line down to the floor and turn back up to form a inverted U, this way i can add the valves? (like the pic in the LAOSH) I will not be able to turn the dry returns up 4 feet (Or is that supposed to be 4 inches?) and still have the 28 inches between the bottom of the steam main and the top of the inverted U, the basement ceiling is only about 7 feet or so. Can i just turn the returns up as high as i need to get the 28 inches? I took some more pics of some measurements but left them at work. Thanks again for your help I appreciate it

Danny Scully

Just so you know...

Just so you know, a Gifford loop would not work in this situation. A Gifford loop does not raise or create a false water line. It's intended to stabilize the water level in the boiler. As far as the 4ft requirement, I actually asked Dan about this. It's not a typo per say, however it's not a necessity. The 28 inches is the most important part, so as Gerry said, FWL or a few cinder blocks.

MikeyB

FWL

Thanks Danny, I thougt i saw a picture of a boiler Steamhead and Gordo had installed a while back and they had to run the return line above the boilers water line, they installed a Gifford loop to cover the dry return w/water, thats what made me think of a Gifford Loop, If i have the 28 inches on the lower of the 2 steam mains to the top of the U and I tee the  2 returns together right at the point i had circled what size should the equalizer pipe be? 1 1/2" or 2" ?  The dry returns that are there now are 1" and 1 1/4" I was thinking of joining these 2 together and increasing to 1 1/2", but if i have to go bigger thats not a probelm. I saw in Peerless and Comfort Calcs literature that they have the distance from the existing dry return to the top of the Inverted U at 4 inches, I guess whatever level you can get to keep those pipes back under water and keep the 28 inches is better that keeping them as dry returns.

gerry gill

you can tie them together

below the new water line without any issue..in the absence of knowing the edr load on the pipes, size the combined pipe for aggregate cross sectional area of both the pipes..can't go wrong that way.

MikeyB

FWL

Thanks Gerry, the Radiator EDR load is about 240 EDR, looks like a 2" pipe will accomadate both returns. A Burnham IN4 will most likely go in as a replacement, Gerry I noticed on your site the Stratford Rd. Boiler Install you have a false water line that picks up 2 wet returns on the floor, It might be easier for me to build it like that and by building it this way you dont need any shutoff valves.

Paul Fredricks_3

4'

I see in Dan's book where it says 4'. Seems excessive to me. Does anyone know why it has to be so high above the water line? I'd have to figure in most applications that would put it near the ceiling, and way into the A dimension.

MikeyB

FWL

In my pics i have a mark for one of the bottoms of the steam mains, and marked down 28 inches, and that mark is a little bit above the 2 existing dry returns, I could only bring the top of the false water line a couple of inches above the 2 existing dry returns to get them both under water, but then i start to decrese my A dimension of 28 inches, see pics, any ideas?