Not venting enough?

BobC

This is a handy guide for clocking your gas meter, note it assumes 1,000 BTU per cf of gas so your actual consumption might be be a few percent highr but it's close ebough.

Bob

agurkas

BobC,
I am actually still running oil. Gas conversion is likely happening in a month or two

nicholas bonham-carter

When you have setbacks, the body thermometer will need a higher setting than if you have the same lower temperature all the time. Try 66 degrees constantly, and see how everyone reacts.
If you have a gas conversion burner, in your boiler, you could have it down fired a bit to match the radiator EDR. It should be done by someone with a combustion analyser.
The low pressure gauge should be standard equipment on every low pressure steam boiler.--NBC

agurkas

Nicholas,
I am still waiting for the conversion. I am sure guy working on it will do the proper setting. But I will make sure to ask.

BobC

I've experimented with different firing rates on my boiler. In my case the sweet spot was about 15% below the boilers nameplate rating. It took more BTUs to produce a given quantity of steam below that. I'm now firing my 105k rated Smith G8 at 90k, yours may be different.

On your insulation question, it seems 1" gives you the best bang for the buck. If the crawl space is much colder you might want thicker in there.

Bob

gennady

You can downfire oil boiler by changing nozzle or adjusting oil pressure. You can't go below 100psi thou.

nicholas bonham-carter

BobC, can you tell more about how you found the sweet spot?

BobC

The Smith G8-3 is rated for 283 sq ft of steam and I only have about 200 sq ft of connected EDR. A bit large but that is about as small as wet based boilers get. I knew I could reduce the firing rate by making the orifice smaller or lowering the gas pressure, I talked to Carlin and they said the acceptable range was 3.2 to 3.8"

When I had the boiler installed it was firing at 110,000 BTU, I turned the gas pressure down to 3.2" and that got me closer to the 105k the boiler was rated for. After the summer I bought a new orifice nipple and drilled it out for 77.6K, I found that was to far underfired and was taking too long to raise steam. I turned the gas pressure up to 3.8" and that gave me 84k. I opened the orifice up by another 64th and that put me at 90k.

At each different setting I used my Bachman 125 to make sure the EZ-Gas was set properly and I timed how long it took to get steam to the end of my steam main from a cold start. I divided the number of minutes by 60 and multiplied that by the burners firing rate (determined by clocking the meter). That gave me the number of BTU's it took to get steam to the end of my main. I found the numbers fell as I reduced the firing rate until I got to 84k at which point the number began to rise. In my case the 90k area seems to be the sweet spot but I haven't really explored the are between 90 and 105 k.

I had the system checked and tuned this week and the tech said it was running as well as any he has seen - 84.5% efficient and all the numbers are well in bounds.

Bob

agurkas

So now that I have 3PSI gauge installed, how do I verify that boiler is cutting in at 0.5PSI I have set on pressuretrol. Cut out is very clear :-) It is the cut in I have no idea how to identify.

Abracadabra

Does the pressuretrol control lo/hi fire? Or does it completely shut off the burner when it hits it's cut-out?

agurkas

Seems like only on and off. Only two wires from pressuretrol

Abracadabra

Yes, there's only going to be 2 wires out of the pressuretrol. If it only controls on/off, then after pressure has hit the cut-out, it will only go back on after pressure has decreased to the cut-in.

agurkas

Ran one heating cycle with the new gauge. Boiler cut out at about 1.7PSI and cut in at ~0.7PSI or but higher. So either gauge is off or pressuretrol is.

Also, is steam trap supposed to hiss and let out bit of steam? Somewhere above 1.2PSI is starts letting out some.

Abracadabra

.7 cut-in 1.7 cut-out looks about right based on the ~.5 cut-in and 1psi additive diff on the pressuretrol.

Is steam trap new? None of the steam traps I've installed as main vents ever leak steam.

This thread has been going on for so long I've forgotten what the problem is. You claim 30 minutes is too long to get a 2 degree rise in room temps. What do you base that on? Assuming about 15 minutes from a cold start to getting steam all the way across all the radiators, then another 15 minutes to get temps up 2 degrees seems ok to me.

RobG

Agurkas, can you please change your profile pic? I finally realized what it reminds me of, the way my late father in law looked at me when I picked up my wife for our first date.

agurkas

RobG said:

Agurkas, can you please change your profile pic? I finally realized what it reminds me of, the way my late father in law looked at me when I picked up my wife for our first date.

Sounds like he had a reason :-) My now father in-law only said "great, you guys will save money" when I told him I am moving in with my then girlfriend (fiance bit came year later)

agurkas

Abracadabra said:

.7 cut-in 1.7 cut-out looks about right based on the ~.5 cut-in and 1psi additive diff on the pressuretrol.

Is steam trap new? None of the steam traps I've installed as main vents ever leak steam.

This thread has been going on for so long I've forgotten what the problem is. You claim 30 minutes is too long to get a 2 degree rise in room temps. What do you base that on? Assuming about 15 minutes from a cold start to getting steam all the way across all the radiators, then another 15 minutes to get temps up 2 degrees seems ok to me.

Re. presuretrol, so sounds like there is not reason for me to blow $180 on a new one.

Steam trap is new. Hence I am weirded out a bit. Need to ping the seller (that is the last time I am buying plumbing stuff off Ebay)

Re. issue with heating up. Running around and switch valves, adjusting those in rooms I don't use, and putting on new vents on all mains has cut down 2 degree change from cold start to 25 minutes. So we are down 5 minutes. Not bad from something like 40 minutes or more, before I started following all your advice and cleaning up things that were not maintained.

Vents still spit water, so I need to redo insulation. The main that has about 2/3 of all radiators (weird, because there are 3 mains), from what it looks like, if I can dry up the steam by preventing premature condensation, I should save a bit.

That still leaves me with one hammering pipe. It was modified by expansion of the kitchen. Big problem I am encountering there is that I can find where it exactly is. I tried measuring, waiting for banging to start, but I am yet to find where exactly it goes...

Abracadabra

agurkas said:

Vents still spit water, so I need to redo insulation. The main that has about 2/3 of all radiators (weird, because there are 3 mains), from what it looks like, if I can dry up the steam by preventing premature condensation, I should save a bit.

What does near boiler piping look like?

agurkas said:

That still leaves me with one hammering pipe. It was modified by expansion of the kitchen. Big problem I am encountering there is that I can find where it exactly is. I tried measuring, waiting for banging to start, but I am yet to find where exactly it goes...

When in the cycle does the hammering happen? beginning/end?

agurkas

Abracadabra, it is a bit of a mess, from what I have gathered in several threads here. Headers are wonky and some of the mains are piped weird.

Re. hammering, middle to closer to the end. I have already lifted the rad in question (only one on that main) as much as I could without cracking a pipe. Used my racing car jack to raise it as close as I was comfortable.

Abracadabra

Do you have a better picture of the hartford loop nipple and where the normal water line of the boiler is?

You can get a good idea of where the problem is by following the steam on the pipe with your hand as the cycle progresses.

Start the boiler, and then with your hand touch the pipe to feel how far along steam is moving. As the pipe gets hot, move your hand to where it's cooler. Continue until you hear the water hammer. You should then have a good idea of where the steam is running into water. If you have a main that's split into 2 or 3 circuits, you might have to repeat this for each main.

Middle to end of cycle water hammer can also mean a clogged wet return. Had that happen to me on a job couple weeks ago.

Mark N

There is a wet return that comes out of the floor that ties in with a what I assume is a drip from a counter row main. I would not be surprised if that is not hammering in the nipple. That looks to be above the water line so there will be steam in there.

agurkas

Abracadabra, I know which main it is hammering in. It is interestingly piped, to say the least. There is, what I call, appendix, which is likely remnant of past radiators. I will do pictures in separate post. Challenge there, that banging happens in part of the branch that are in the wall.

Mark, you are correct re design deficiency, that is one of the problems identified by several people, who have seen the Frankenstein of a piping job. But that wet return does not hammer. Will include pictures in separate post.

agurkas

Here are the pics

agurkas

And this is what it sounds when that radiator has boiling water noise inside: https://dl.dropboxusercontent.com/u/6292455/2014-10-21 03.04.20.mp4

Abracadabra

OK.. I just listened to the mp4 file. You don't have water hammer. Why do you have that big of a vent on that radiator? Put a slower vent on that radiator and make sure it's pitched correctly. It sounds like you might need to replace the shutoff for that radiator too. Sounds like the disc is loose or it's fallen off the stem. If the valve isn't fully open and the disc is causing a restriction, it'll block some of the condensate from leaving the radiator as steam is trying to rush in with that huge vent you got on it.

agurkas

Was not able to catch water hammer in the video. It is sporatic. Sometimes it does not happen at all.
Vent on it is a Gorton C and main is vented with Gorton 2. Main is about 10 feet of 1.5" and that particular branch is about 9-10 feet to the 2nd floor.
Vents upstairs I did by Gorton diagram. Now that I have the books, I see where I may have oversized some.
Not looking forward to having to cut into that valve. I can easily disconnect the radiator, but the valve body is not budging and I don't want to crack the pipe. Likely will need to do what I saw in those youtube videos and cut into the base of the valve, crack it with a chisel to loosen the thread.

BobC

If you never actually use that valve you could just open the union and look into the valve to see if it's broken. If it is you could try to pull the broken disk out and then reconnect the radiator. Then deal with replacing the valve in the spring when you don't need the heat. Mr Murphy delights in making things go wrong at the worst possible moment, don't give him the chance.

Bob

agurkas

I love this forum! I wish there was one like it for electrical. Reddit/Electrical is just to inconsistent with answers. And sometimes you get the grumpy ones. Not the case here.


Bob,
I did look into the valve and
1. the disk was not all the way up. It was like 1/4 way down and won't go higher.
2. I do recall disk was a little bit loose. Not much play, but enough for me to notice.

SWEI

Try http://forums.mikeholt.com/ for electrical questions.

agurkas

But are they as friendly to DIYers as people here? :-)

SWEI

Helpful, but somewhat intolerant of fools who insist on trying to kill themselves despite advice offered.

agurkas

Fair statement. That said, steam gives me bit of adrenaline too. I've had some stuff blow up on me before under pressure. So I do look at boiler as I look at an electrical panel (especially around 200Amp breaker) - I don't want to do anything that will make those "angry".

KC_Jones

agurkas said:

Fair statement. That said, steam gives me bit of adrenaline too. I've had some stuff blow up on me before under pressure. So I do look at boiler as I look at an electrical panel (especially around 200Amp breaker) - I don't want to do anything that will make those "angry".

Reminds me of the time I accidentally pulled a bare 14 Ga conductor across both bus bars and a good ground in my main panel...the conductor vaporized. I did a very stupid thing. About your radiator, I actually had one making the exact noise yours is making. My problem was I had the valve closed and it filled with steam, condensed then filled with water and the noise was the steam gurgling through the water. If yours is open as much as you say I can't imagine it's that, but really sometimes weird things happen on these systems. Could this be a wet steam issue? Too much wet steam in the system and too much steam getting to this rad because of over venting? As far as getting the valve all the way open. Did you try removing the valve or did you try unscrewing the bonnet on top? Those valves can be serviced without removing them. You could maybe try spraying some penetrating oil into the stem and try to free it up. Just some thoughts from another homeowner. I agree I wouldn't mess with the valve too much during the heating season.