System Pressure

Aveeight

Hi all - same caveat as my last post - probably naive questions but just trying to learn.



The steam system I have has a pressure release valve at the end of the system. I use a programmable thermostat that drops the heat down to 64 at night and back up to 68 in the morning. When the system comes on to heat the house it has to work for about 45-60 minutes or more and the steam release deal at the end is always going after about 20 minutes. It seems like this is wasting energy and the system could just cycle off for a while as the radiators which are already very hot continue to heat the house. The pressure value, which looks exactly like this <a href="http://www.inspectapedia.com/heat/SteamHeat030DJFs.jpg">this</a> is set to just about 1. There is a gauge next to it that never seems to move at all - it doesn't even seem to get to 1.



My question is should the system be shutting down or is it normal for that much steam to be released?

crash2009

There are some advantages

 to programming your thermostat to be the same temperature all the time.  Whatever you think you save by setting it back you lose by warming it up in the morning.  That thing you labled as "This" is called a pressuretrol.  It is adjusted by turning the screw at the top.  When you turn the screw counterclockwise you lower the indicator. 

The "pressure release valve" is normally mounted right on top of the boiler.  I think you are calling your "main vents" "pressure relief valves".  If they are attached to the pipe at the ceiling and are 10-20 feet away they are likely main vents.  They should not be releasing steam.  This steam release indicates they are not working right.

Can you take a few pictures for us so we can label all these parts for you? 

BobC

Clogged pigtail?

Your system has a pressuretrol (the picture you referred to) which is supposed to shut the boiler down at a particular presusre (usually 1-1/2 to 2 PSI), the safety is set for 15PSI. The pressure relief valve comes directly off the boiler. If the valve that is going off is on the end of a large steam main in the basement it is a main steam vent. A main steam vent will vent air when the system starts to build steam pressure and it lets air back into the pipe when the system shuts down.



If that safety pressure relief is going off you have a dangerous situation on your hands. Those safety's are not designed to pop off on a regular basis, it is a warning that something may be seriously wrong.  If it is the main steam vent your ok.



What does the pressure gauge read when the boiler shuts off?



Below the pressuretrol there is a curly pipe called a pigtail, it may be clogged and that is preventing the pressiuretrol from seeing the pressure inside the boiler. this is only true if it is the pressure safety relief valve that is going off.



If the safety relief valve is popping off, get this boiler looked at as soon as you can for your own safety.



If the pressuretrol is shutting the system down because it reaches it's set point it's just doing it's job. Also that front tab should be adjusted down to 0.5 (screw on top of the pressuretrol) and the dial on the inside should be turned down to 1). that will let your boiler cycle between 0.5 and 1.5PSI until the thermostat is satisfied.



Those 0-30PSI gauges are not very good at the low end of the scale.



Bob

Aveeight

Fix for pressure and pigtail?

Thanks for the replies.



I will try to get pictures tomorrow evening and post them up.



Bob - the steam pressure relief is not going off, it is the main steam vent from your description.



I think the pigtail is clogged like you mention. The guage (0-30) never seems to move and I have the pressuretrol (thanks for the vocab crash) set to .5 - 1.5 and it doesn't seem to do anything. The pig tail is hot before the twist (closest to the boiler) but cold next to the gauge and the pressuretrol. How do I clean or fix that? If the boiler is off (off at the main shut off) can I just unscrew it and clean it out with a pipe cleaner or something? Will I be able to just manually screw it in/out? It has sort of a pink teflon tape on it now - should I replace that?

Rod

Pigtails

Hi- sometimes it is easier to just buy a new pigtail. Get one is red brass(bronze) as they don't corrode and plug as quickly as steel.  If you can't find one locally, try McMaster Carr   

http://www.mcmaster.com/#pressure-gauge-pigtails/=afrob5    

The pink tape is teflon tape. Use a couple of wraps in the threads to seal them. Make sure the burner is shut down before and the boiler reasonably cool before rmoving the pigtail.  You'll want a pigtail with 1/4 inch MPT thread on each end.  (MPT= Male Pipe Thread)

If you don't have one already I'd highly recommend you get a steam book that it available on this website. It's called "We Got Steam Heat!". It written for the homeowner new to steam and  gives you tons of info on steam heating, It pays for itself very quickly with good tips on how to get your steam system up to par.

http://www.heatinghelp.com/products/Books/5/61/We-Got-Steam-Heat-A-Homeowners-Guide-to-Peaceful-Coexistence

- Rod

jpf321

where are you?

perhaps someone can drop by and give you a crash course on your system.

Aveeight

West of Philadelphia

I would love that, or even if I could find a weekend or evening course or seminar on the basics. It always seems impossible to find though.

Aveeight

Just bought the collection

Just ordered the 3 book collection from the store - hopefully that is a good primer!



In the mean time, when replacing the pigtail, do I need to get a standard or high pressure pipe?



The pressuretrol and gauge are connected to the pigtail with a sort of t junction - is that ok to leave?



Is disconnecting the pressuretrol straight forward? it is connected to the power box via MX - can I just disconnect the wires in the pressuretrol so I can unscrew the entire thing?



When reconnecting it, is manually tightening sufficient? Does the loop face down or up (right now the male ends are on top and the look is on the bottom)? I would worry about it blowing off with the pressure.

crash2009

This website is the best resource on the internet.

 Most of the time when I google something, I end up back here anyway.  Check out the resources section at the top of the page.  The library is jam packed with steam stuff.  This video is one of my favorites, I learn something new every time I watch it.  http://www.heatinghelp.com/article/107/Steam-Heating/118/Steam-boiler-near-boiler-piping  This video is just a small sample of what you can discover in the Heatinghelp Library.

Rod

Pigtail

Hi- Good to hear you ordered the books. Read "We Got Steam Heat!" first as it gives you the terminology and a good introduction to steam. (I read "The Lost Art..." first and it was the hard way to go!)

Get the standard pigtail in red brass. Residential steam is very low pressure (under 2 PSI)

Yes, You can use a tee and put the pressuretrol one one branch and the pressure gauge on another. You might want to use a tee instead of a elbow on the pressure gauge so you could easily add a second gauge. The 0-30 PSI gauge that comes with the boiler is required by insurance /code so therefore you need to leave it attached to the boiler. However most people add a second 0-3 PSI gauge as this makes it easier to see what the pressure is doing.

Disconnecting the pressuretrol is straight forward. Make sure the power is off by  pulling the circuit breaker leading to the boiler.

Installing the pigtail- The function of the pigtail is to protect the pressuretrol and gauge(s) from live (hot) steam. To do this there is a loop which traps water. The water in the loop prevents direct contact of the steam with the gauge /control. The pigtail and pipe fittings should be configured so as water drains away for the pressuretrol /gauge(s).  Use Teflon tape around the threads and screw it in by hand to a snug fit. (Again remember this is a very low pressure system so it if snug it won't "blow off")

The pigtail should be oriented so that when you at standing in front of the boiler you can see the loop. If the loop on the pigtail is oriented sideways, the expansion /contraction of the loop tilts the pressuretrol slightly on and on the older type pressuretols this can result in erratic operation.

Welcome to the World of Steam Heating!

- Rod

Aveeight

Pictures as promised

Feel free to comment away - I have no idea what about 50% of everything is (the other 50% I learned here over the last 3 days).



I tried to remove the main vent at the end but it seems to be rusted/corroded in place - I'd like to replace it or at least clean it out because I think it is stuck open - any options?

crash2009

The water in the sight glass looks pretty dirty.

  If it was mine, I think I would call up a pro to get it clean for you, then get the main vent working.  This would be a temporary fix just to get you through the winter.  A complete flush would mean it would be shut down for 1/2 a day, Ask your pro to flush it, flood it, check for leaks, and advise you on the condition of the boiler.  Then decide whether re-pipe or re-placement was the right choice for you.  Then I would start planning to make some big changes in the spring.  Copper, steel, and steam dont get along very well together.  Have you looked in the "Find a Contractor section" yet?  I labeled a few of the parts for you

BobC

Remove vent

There is a 3/4' coupler between the main vent and the 3/4' pipe, you will probably have to put a torch on that for a good while so you can heat it up enough to expand just a bit. Be caeful not to heat the vent, just the coupling, because you want the coupler to expand.Then you should be able to loosen up that vent.

Rod

Labeled Pictures

Hi- I labeled your pictures so you can apply the terminology to the parts. While copper piping is frowned upon for steam piping ( the constant expansion /contraction of steam heat tends to break the joint apart) if it isn't causing a problem I would just leave it be.

Your boiler Riser and Header are of good height so that should be giving you dry steam.

You'd probably get a good benefit by insulating the Boiler Riser,,the Header, and the Riser to the main and the Equalizer pipe down a foot or so,

It would appear from the coloration of your sight glass that your boiler could use a good cleaning.and have the burner and combustion checked. This should be done once a year though you might want to wait until spring when it warms up to have this done.



Your pigtail is brass so it is probably worth just cleaning. With iron ones it is better to just replace them than clean them.

- Rod

Rod

Gauge & Control Setup

Hi- Attached is a typical piping diagram for two gauges and pressuretrol. It gets the control and  gauges farther above the boiler waterline. If you did something like this on your boiler it looks like you would have to lengthen the wiring to the Presuretrol a bit..

On your main vent, it looks like you need a new one. Get the pigtail cleaned first as the high pressure might damage a new vent.

 Could you post some pictures of the main vent and connected piping and also of the piping where the riser from the boiler attaches to the mains. Take the pictures from farther back as we can then trace the piping.We can blow the pictures up if we need detail.

- Rod

Aveeight

You guys are why I love the internet

Thanks! I am sure I will have more questions but so far you have showed started me on the insanity of steam heat!

Aveeight

Vertical installation of pigtail

is ok? It doesn't have to stay horizontal with the loop on the bottom to keep the water in the loop? And splitting the pipe 3 ways won't affect the readings at all?



Thanks for the picture - makes it easy to purchase? Where can I expect to find all of that? At a decent plumbing supply store?

jpf321

shopping for parts ...

as mentioned in the drawing, all pieces should be brass ..



the best supplier I have found is www.simplyplumbing.com .. everything you need is there .. including pigtails ..



what is missing from the picture, is a 1/4" brass union .. i always like to put a union on so that come pigtail cleaning time, I can simply de-union the tree from the pigtail without messing with the wiring .. in this case, the best place for a union is at the top of the pigtail perhaps .. is you add the union, make sure to get 1 pc of 1/4" Close nipple as well. the union would thread onto the pigtail .. the other side of the union onto the close nipple and the close nipple into the horizontal T.



for an extra few bucks, i would get a handful more (perhaps 3extra pieces each) 1/4xCL, 1/4xSHL, 1/4x2 .. you don't want to be in a position where you are running around trying to find them when you've got everything taken apart and you need 1more piece. BTW, CLOSE is smallest nipple, SHOULDER is usually the next size above CLOSE, and then nipples run in inches of length depending on the diameter of the pipe. 1/4" seems to start at 2" .. larger size pipes could start at 2.5 or 3" in length after CLOSE and SHOULDER.



simplyplumbing links:

1/4" brass nipples: http://is.gd/kcxgi

brass threaded fittings: http://is.gd/kcxkU

brass pigtails: http://is.gd/kcxtK

Rod

Parts

Your pigtail will still have a water trap in the vertical and more importantly excess water will drain easier back to the boiler, away from the gauges/control. The higher above the boiler waterline, the less likely for water to get to the gauges/ control.  These parts should be available almost any where .Other than possibly the pipe union jpf mentioned, the parts should be available at your local Home Depot.

- Rod

jpf321

HD's vary store to store ..

My local Home Depot *just* started stocking 1/4" black .. and all the brass bits are baggie'd and expensive .. they also don't have pigtails .. according to the HD website, they really don't have anything in the way of 1/4" brass fittings .. they have some 3/8ths

crash2009

My only concern with the copper

 was the appearance of the 2 joints I circled in green.  Maybe the picture is deceiving, but they don't look the same as the rest.  I would get an onsite professional opinion.  Unless I was assured here, that they look OK.

Aveeight

Isn't the point to trap water?

I thought the point of the pigtail was the trap water so the steam never hit the gauge direction? If its above the water line how will that happen?

Aveeight

Yup

Those are quite corroded and I called for an appointment with a local plumber who specializes in steam piping yesterday. They don't seem to leak at all and seem solid now - but I think they just corroded over, they seem to be purple in places!

David Nadle

condensation

Steam eventually condenses and the bottom of the loop quickly fills with water. If you're concerned about it you can always pour a shot of water down the pgtail before you mount the equipment on it.

Rod

Trapping water

The idea of the pigtail is that is traps a little water which then forms a barrier between the gauges/controls and the live steam.entering the pigtail from the boiler.  . Look at the pigtail in the picture I posted earlier. It will trap water but any excess water in the pigtail will drain back to the boiler. On your pigtail as it is installed now,it will trap water but it is also the low part of the line so all the "crud" collects there.  There will always be water in the pigtail as steam entering the pigtail condenses though it's a good idea to "preload" it with water when installing it.

- Rod

Rod

Let Sleeping Dogs Lie!

While we all know that steam piping should be piped in black iron with threaded fittings, I'm also a great advocate of "if it ain't broke don't fix it!". The riser and header configuration is pretty good and the system has been operating this way for 15 years! (See attached picture)  If it were me I think I'd just wait until it a problem actually developed or till  the a replacement boiler was installed.

- Rod

Aveeight

Couldn't agree more

And the last thing I need right now is a costly pipe replacement. He is coming to look at some small sized potable water pipes, a leaky pipe union, and maybe crack the boiler drain faucet off and replace it - and generally evaluate whats going on, nothing specific to those pipes. The dogs who are sleeping and moving steam shall remain undisturbed.

Rod

Adding Water to Your Boiler

You may already know this but since you are working on the boiler drain I thought I'd better mention this just in case you don't know this already. After adding fresh water to the boiler it  is very important to always bring the new boiler water to the boil as this drives off excess dissolved oxygen. The excess oxygen can be very corrosive to your boiler and shorten its life.

- Rod