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Jamie Hall

Jamie Hall

Joined on September 16, 2002

Last Post on April 18, 2014

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As Al says

@ September 6, 2007 9:09 PM in 2 pipe vapor heating system

need a lot more information. That said, it sounds as though there are a couple of oddities there. If the radiator traps are working, and the returns are to a wet return only, I'm not sure that I quite understand what the float air eliminator and boiler return trap are doing in there. Shouldn't need them. If you really do have a differential loop in there, that's great -- leave it. Just make sure the pressures on your new system are in the ounces range, not pounds, or differential loop won't work at all. There are a lot of good boilers out there. Give us some more info...

Hate to admit it but

@ September 6, 2007 9:03 PM in Just a question about you guys

Mechanical Engineer (PE) and now building superintendent (which basically means that anything that doesn't work I get to take a whack at it... or call a pro, which I often do!)

a comment on slope

@ September 6, 2007 9:00 PM in Help me understand my mains

it it isn't hammering, and you aren't seeing the boiler overfill (your condensate is getting back OK), it ain't broke and you don't need to fix it... the slope of the mains, that is!

So Georg

@ September 6, 2007 8:51 PM in Changing steam radiators to hot water

I have one question which I haven't seen in this thread: why do you need to change to hot water? As someone pointed out, the theoretical efficiency of a really good new hot water system (mod-con) is better than good steam (particularly the Burnham someone mentioned) it isn't enough better to recover your investment in the change over -- even if the old rads don't leak. But they will... dang near guaranteed. I'd find a good steam pro (they're a little thin on the ground) and fix the Cadillac you've got, rather than buying a new Chevy.

too many variables

@ August 30, 2007 8:12 PM in Engineering new steam system from scratch?

to make a good comparison. It would have to be done in a lab. setting, and it would be fascinating. As to the 140 water vs. 212 steam vs. the flame temperature. Um. Well, keep in mind that the flame temperature is around 1,000 plus; the difference in cold side temperature is trivial (and a good bit of the heat transfer in steam is at less than 212 anyway). One could build an exhaust condensing steam system: use the exhaust flue gas in a feedwater heater. No big deal. I doubt very much that the cost would be recoverable. As several has said, the real key is zoning -- which is just as easy to do with steam as with hot water.

I don't think so...

@ August 21, 2007 7:50 PM in Converting Steam radiators to Hot Water

by the time you get done repiping and replacing the boiler, your capital investment is durn near guaranteed to be greater than any conceivable savings you might get from lower fuel consumption -- which will be minimal anyway. Anything you can do with HW can be done with steam and, if the steam system is already in place, usually it's easier and cheaper in steam than in HW. Keep the steam.

Whoa there...

@ July 10, 2007 9:19 PM in firing 2 pipe steam for low pressure

that's a serious boiler. Can you give us all more specs on the heating system? And what else, if anything is hooked up to that boiler? That much pressure doesn't look like your average steam heat system to me...

and may I add

@ July 5, 2007 5:54 PM in Any reason NOT to always use full port ball valves?

having found out the hard way -- there is a very good reason NOT to use reduced port ball valves on low pressure (or vapour) saturated steam: the pressure drop through the reduced port will condense a substantial fraction of your steam, and you've got no heat... (saturated steam is funny stuff).

Um... well...

@ June 30, 2007 9:35 PM in heat loss

I think this is a first: gotta debate a little with Brad. It is quite true that insulaton will help a great deal -- given two things, which may not be possible with an old house (like, for instance, mine). First, can you get it into all the spaces? Like ALL the spaces? Otherwise, the infiltration will still be pretty bad. Second, and much more important, can you create a positivie vapour barrier on the inside? If not, you can kiss your outer wall goodbye, as well as at least some of the framing and the paint. Which just could get expensive... All of which is why my house is NOT insulated in the walls (it is, attic and basement walls)

You should be fine

@ June 27, 2007 9:19 PM in #1 Hoffman differential loop

provided, as Gerry says, you make sure all your wet returns are covered, particularly at the far ends of the lines. You may find the odd drip at a remarkably high elevation... The differential loop itself works dandy, provided it is high enough. Oh yeah. Also -- the differential loop works dandy, provided the pressure is low enough. Use a vaporstat.


@ June 10, 2007 6:45 PM in What's in your driveway?

The Chevy '94 K2500 work/tow truck, and the horse trailer that goes with it. The '70 C10 long bed step side I can't bear to part with. Mom's '97 Saturn wagon. My '04 Honda Hybrid. And the '51 Ferguson TO-20 tractor... rest of the stuff's out behind the barn instead of in front of it!

These puppies

@ May 31, 2007 9:21 PM in EDR for an old style ceiling radiator

were also used on the ends of the steam mains in some installations, as 'condensors'. They helped get steam to the ends of the mains in a big big hurry, and didn't hurt the overhead warmth any. I have two in the basement -- one at either end -- at the ends of 75 foot 3" mains.

One size

@ May 31, 2007 9:09 PM in solar

does Not fit all. My father in law -- recently passed away -- was one of the major pioneers in semi-passive solar space heating, based out of the Boston, MA area. I did a lot of his arithmetic and dog work for him. Solar is excellent for space heating -- even in New England. 50 percent is easy; 80 percent not so easy, and 100 percent hard, but doable. However, that said, to get up around those figures, every structure is different, and retrofits never get that high, or even close. A few general rules: lots of storage. As someone said, KISS is not just a band! Make sure you have enough air changes per hour (outside air). Keep your heat storage at as low a temperature as is feasible (we used around 120 to 130 for space heating).

Get Matt

@ May 31, 2007 8:57 PM in Should I convert from steam heat to hydro air heat and cooling

to come out and look at and tune the steam system. Then you'll have the best heating system money can buy -- for practically nothing. After you've done that, find a really good air conditioning contractor to design and install a really good air conditioning system (all the posts above mention good systems, except the ones mentioning combined fan-coils for both heating and cooling, which aren't worth the powder to blow them up). Then you'll have the best air conditioning system you can get. And be very happy.

oh no not again..

@ May 31, 2007 8:51 PM in Replacing steam with forced hot water

Read Steamhead's reply. Then read it again. He really does know what he's talking about. The only thing I might add is that any minute gain in efficiency you might conceivably achieve would be so small that the pay-back on the cost of conversion would take you well past the end of the next century. Don't Do It!


@ May 16, 2007 9:20 PM in convert 3phase to single phase

check the actual voltage rating of the heating elements -- it varies, depending on how they are connected (delta or wye) and the grounding of the whole thing, as well.

Vapour barriers, etc.

@ May 16, 2007 9:16 PM in Rather Odd Heating System

Those light fixtures will be a problem. It doesn't take much of a hole to allow the vapour up through, and it doesn't take much vapour to create condensation; rot is usually less of a problem than mold, though. Mold can be a real problem. They can also be a problem if they are not rated to be wrapped in insulation -- a lot of ceiling can fixtures aren't, and can overheat very badly if surrounded by insulation -- a real fire hazard. For the foil/bubble stuff, try; very good outfit, very prompt and helpful. They also have a variety of nifty (and very agressive) tapes for sealing seams and the like. The rigid board above the pipes (only) would work, if it is the sort which has foil on one or both sides (which, incidentally, has a better R value, too). It is almost impossible to seal rigid board well enough to form a vapour barrier, though. Not much vapour will get through a standard joist, but the insulation value of a standard joist isn't all that good. You'd be welcome to send me a personal e-mail on all this, if you want -- Jamie


@ May 13, 2007 8:47 PM in Rather Odd Heating System

Terry -- You don't say it, but you imply that although you are going to use the attic you want to keep it cold. If this is the case, your big problem is going to be condensation: you will want a really good, really tight vapour barrier between the attic and the rest of the house. I would still be inclined to use the foil/bubble/bubble/foil above the pipes you mention, although it's not the cheapest stuff around (about $.40 per square foot). You can get it in 8 foot widths, which might be a bit of a bear to handle in your situation (working it over the pipes) but that would reduce the number of seams to tape. Another possibility would be to use the foil only over the pipes, but put a solid vapour barrier on the floor of the attic, cover that with rigid foam and cover that with a new floor (the R value of foam varies; adjust the thickness as necessary). Think outside the box... Whatever, if that attic is going to be cold, get a good vapour barrier in there!

Find a Pro

@ May 12, 2007 8:04 PM in noisy riser pipes (an understatement)

Rachel -- check out find a pro, right here on this web site. Click on it and give your zip and there you are. Some of the best in the world are at your mouse's beck and call, and live within a few miles of you.


@ May 10, 2007 9:15 PM in anode rods

is better if there is much (or any...) sulphur or sulphate in the water -- magnesium combined with the sulphate produces a weak solution of epsom salts! But magnesium will give more agressive protection, in general


@ May 10, 2007 9:13 PM in Rather Odd Heating System

sounds like the plan -- just make sure it's supported well, with the foil side down towards the pipes (and you). These overhead systems (I've seen some electric ones, too) are basically radiant heat; different (I don't care for them, or for the heat quality) but they do work and some folks swear by them.

ball valves

@ May 9, 2007 6:31 PM in Questions for you engineering type guys

I've never been real happy with ball valves as throttling gadgets. Bob mentioned the double seated steam valves (in effect, a form of double seat globe valve; inherently balanced and excellent controllability) and Brad mentioned the camel's toe variety of ball valve, which also works. If you are throttling saturated steam, you need to be just a little careful -- but you seem to have ample pressure. I'd rather mix the water...