Questions about improper header efficiency, cracking top of boiler, and hartford loop

SteamingatMohawk

News flash! Which is first, the chicken or the egg?

I just read in Lost Art - Revised on page 104, "To get away from check valves, heating engineers used a "bleeder" (what we call now an equalizer) to take the place of the check valve. This was years before the Hartford Loop was invented."

midiman143

Thanks for all the debate guys. As a newbie im glad to at least see that my original question about the hartford loop were based in reality that it is layer of safety working in conjunction with the low water cutoff , equalizer and potentially pressuretrol.

midiman143

@ethicalpaul can you elaborate on this? My first thoughts would be that 2 pipes allows more steam in the headers, reducing the velocity therefor reducing the amount of water in the headers and creating dryer steam. Is it "needed" I could only know that by seeing it operate and how much water was getting forced up the header but it seems like a good practice right?

ethicalpaul said:

Just one of the weird, wrong things in that article:

Also, most steam boiler manufacturers now require that two-pipe systems be installed.

ethicalpaul

They are overloading or misusing the term "two-pipe systems".

do they mean two-pipe as in the kind of more modern systems where each radiator has two pipes going to it?

or are they referring to piping a boiler with two steam supply pipes?

Additionally, I think you'd be hard pressed to find a manufacturer nowadays that will "require" anything at all. They won't even call out installers who totally botch a nice new boiler install. But I digress.

I would say that installers should follow manufacturers' recommendations. But this is a case of do as I say, not as I do, as I did use both supplies on my tiny boiler. But I'm not a contractor who is trying to win a bid or finish a job on time.

Here is my video about that: https://www.youtube.com/watch?v=4IymyZB4wlI

EBEBRATT-Ed

There is another important reason for a Hartford loop, and many will disagree with this rule because it is an ASME rule an a lot of residential boilers and small commercial boiler (and there installers) are not inspected by anyone who knows anything about the ASME code

If you have multiple boilers (steam) you can't connect them together below the water line unless you have check valves and or Hartford loops.

Important reason is that failure of one boiler (leaking) could cause the other boiler to fail if the water in the good boiler was lost due to going through the return line and leaking out through the leaking boiler.

Hartford loops and or check valves prevent this from happening

It is the insurance company on commercial jobs preventing against boiler loss. That's why these rules were made.

Also from the "Lost Art" pg 102 & 103

"all it took in the old days to blow a boiler sky high was a leaking wet return line" The boiler started to go dry and the water feeder came on and the boiler lifted off, Don't forget they had water feeder before low water cutoffs were invented and there was no way to shut down a coal fire anyhow,

"today we have reliable low water cut-offs and automatic water feeders, but the Hartford Loop is still very important because it serves as a back up to the low water cutoff and most important it cuts out the need for a check valve in the wet return"

SteamingatMohawk

So far, I have found the equalizer was "born" before the Hartford Loop.
I still haven't found out when the feeder (presumably automatic) was"born", but it must have needed a water level device to actuate. So, did the first LWCO have a function to control the auto feeder? Were they born as twins?

Who knows?

EBEBRATT-Ed

@SteamingatMohawk
Feeders worked off of float controls. No low water cutoffs at the begining no electricity didn't need electric for a coal fire just a shovel and a match.

The old feeders they ran the city water into the float control and from there into the boiler. And I think they dumped water if the boiler overflowed.

SteamingatMohawk

Thanks, that shows my lack of knowledge of float controls. I think I like my probe unit, no moving parts to get sludged up, just coated over time.