Trying to understand my Vapor-Vacuum system

MotownSteamer

Hello, Scott the homeowner here. I've done considerable work to my two-pipe system this fall (new main air vent, new radiator traps, new crossover vents (traps), cleaned the pigtail and replaced the piping under the Pressurtrol and gauge). I'm still trying to figure out exactly what my system is, and what else I should do before starting up for the season. Here are some pics. I suspect the big black component is a boiler return trap, and of course we have check valves. I do not understand the piping behind the boiler; where is the equalizer, is there a Hartford loop or not, and why are some of those pipe insulated? Should I tear into the boiler return trap and inspect the parts? What about the check valves? Can I drain enough water via my low water cutoff to get at the checks? Should I leave this stuff alone? I want to avoid the system problems that I've worked hard to prevent by all my other efforts. I've got the pressurtrol cranked down, but obviously someone cranked it up years ago trying to overcome something. Please advise.

Joe V_2

that black thing

might be a heat exchanger for the homes hot water.  I had one but I don't recall a pipe coming from the top like yours.

Tim_Hodgson

It looks like you have a Trane

boiler return trap. The two pipes coming out of the top are connected to the steam supply and the vented condensate return piping. The float alternates which one is open or closed. I have seen the return traps piped into a Hartford loop and I have seen them piped directly into the bottom of the boiler. The system will work fine either way. I would not take the return trap apart until it fails. You have a sediment trap on the piping before the first check valve, to keep the traps clean. If you desire you can clean the sediment trap and check valves. It is good that you have lowered the pressure setting. Confirm the main air vent and end of main vent(s) are functioning and the system should cruise through the winter.

Good luck,

Tim H

MotownSteamer

Yes, it is aTrane

A #11 Direct Return Trap to be specific. Thank you for clarifying. Any way to confirm it is working? And, to inspect and clean the check valves, I need to drain some water, right? Otherwise I will have a black, goopy flood when I crack those covers open, right? I replaced the original Vacu-Vent with a B &J quick vent. New cross over traps too.



Have I considered everything?

Jim_184

Jim

It looks like you're in pretty good shape. You have a variation of a Hartford loop which will prevent , in the event of a leak, will limit your boiler's water loss and prevent a burn out. It appears you have a boiler return trap the purpose of which is twofold, purge the air out of the system that's coming back from all your radiators and facilitate the return of condensate to the boiler. This is kind of an old fashion purely mechanical device and you might want to think about replacing it with a condensate return pump. Finally, you might want to talk to your contractor about a simple conversion to a vacuum system. Properly installed and maintained this system would allow you to use 160 to 180 degree steam, saving money while distributing steam faster and more efficiently through your system. ( high pressure steam is dense and sluggish.......good rule of thumb for a heating system: the LOWER the pressure the better. Finally, check all your traps: remove the thermostatic cage unit, wipe the interior down and replace if there are any sighns of wear and tear.

moneypitfeeder

Trying to understand too

I have a an old vapor system as well, with the giant return trap and air eliminator lurking in the piping behind the boiler.Here's a brief description of what I found when opening my system, that might help you out.

Once I opened the return trap, it was full of rusty smelly muddy muck. The return it fed was completely clogged with black "stuff".  The check valves still functioned, but due to the "stuff" clogging the line they didn't see much water.

The float mechanisms in both the return trap and air eliminator were completely seized. I had to pull everything apart and clean and polish all the moving parts. Didn't take that long, and was fairly easy, just had to be careful not to break anything due to all the corrosion, certain parts were more difficult to break free.

Ultimately from what I've been hearing on the wall the return trap will really never come into play if I keep my pressure low with a vaporstat, and I have an auto water feeder. So in theory it will never have the chance to work, but it it ever does have that chance I wantit to work as it was intended to.

Jury is still out, I should finish repiping this weekend, so until I power her up, I won't know if I have helped the system or not. Here's a link to the guts of my return trapttp://www.heatinghelp.com/forum-thread/136523/guts-of-a-marsh-boiler-return-trap-with-pics

Good Luck, Dee

Steamhead

Not quite

on the Trane system pictured, the "Direct Return Trap" was there just to make sure the condensate could return if the boiler's pressure got too high to prevent gravity return. The DRT is basically a pump that works off steam pressure.



These later Trane systems generally used standard types of main vents on the steam mains and dry returns, though I have seen these systems with crossover traps connecting the steam mains and dry returns.



The DRT was necessary because with the regulators then available, it was difficult to keep the boiler pressure below a pound, as these systems required. Nowadays, we can do this with a Vaporstat. So if the DRT fails, we can simply remove it, take the flappers out of the check valves and install a Vaporstat to keep the boiler pressure low.



For this reason, a condensate return pump would not be needed. Not only would a pump add moving parts by itself, but it would need additional traps placed out in the system to keep steam from reaching it. More moving parts mean more servicing is needed in the future. A Vaporstat is much more economical.

MotownSteamer

Thanks for all the replies

All of the feedback is helpful! Yes, my system has crossover traps connecting some steam piping to the return piping. I also have a new quick vent in place of the vacu-vent on the dry return. I lowered the pressurtrol,, but I like the idea of a vaporstat too. I'll post my results when I fire up.....soon.



I still need to understand the procedure for inspecting/cleaning or removing the check valves?

moneypitfeeder

I think your ? got lost

Try reposting a new question just about the check valves. I feel bad I can't give better advice, I just had several of them apart by taking the piping to them apart, so I could clean them from both ends but not the top. It is my guess that they are supposed to be able to opened by the top nut on the valve, and the flapper path cleaned from there, but I was not able to break the cover free to be able to back that info up. If you post a new ? someone should be able to give you better advice.

Good Luck!

MotownSteamer

Those checks

Have clean out caps, so yes....hopefully I can get at them. And, I guess the question about draining is self explanatory, so I just need to plunge ahead. In fact, I need to decide whether to replace the boiler now or not. If not, it needs to be drained anyway.



By the way Dee, I've caught up on your threads; the work you've done on your system is amazing! Keep up the great work and be sure to post pics after you insulate!