Did he Almost Dead Men Mess This One Up?

ctjomac

Watching the steam section since we bought the house...bought 2 of Dan's books. We got the house a few years back and I'm changing the system out! Currently eating 200 gallons of fuel oil every 4 weeks to heat 1150 sq. ft. /388 sq. ft. EDR....just too much. Bought a Burnham MST 396 w/o hot water coil and have a few questions for you Pro's (not many if any here).

See attached pictures:

Dimension A is suppossed to be 28" vertical drop to the NWL according to what I read and I have less than 24". When I install the new one I will need to drop is further?

I have 2 main lines, 1 on front side of house and one on rear, both equal mains about 25' before taking a 90 degree turn and head back towards the boiler. Main vents on both the front and rear loop are smack dab in between 90 degreee elbows (packed with asbestos). Question is can I put them AFTER the last riser about 1-2 feet BEFORE the critical 28" vertical drop on the dry return? Also, the Hartford loop nipple is about 4"...not a y or close!

Seems to me I've got problems that have probably been built into the system since 1933...as the only thing that looks newer is the wet returns and maybe 10 feet of dry return.

Last Question: I wanted to know if I could install a tee instead of an elbow at the return to condensate to the boiler for a indirect hot water heater. The supply to the heater is also on the rear of the boiler about 2" or so below the NWL.

I'm piping in the new indirect now and plan on making the change over sometime late December...early January....Thanks Musch for any advise...Joe

furnacefigher15

nwl?

NWL = what? New Water Line?



Indirect feed- you can put the return from indirect in with condensate return (after hartford loop), but the supply should be taken at a higher point, a few inches below the water line. I believe burnham gives special intended taps just for the use of an indirect.



Be sure to use flow checks on both sides of the circuit, and good ones.



I almost never see a y fitting on a hartford.



How close are the vents to the elbows?

ctjomac

Vents are between 2 90's

4" apart...What's a really good flow check?

furnacefigher15

Flow check

Like a bell and gosset weighted flow control valve.





Are the main vents bad? Do they hammer? They are a little close to the elbow. as long as they don't hammer, I'd leave them there and add the ones you mentioned.





Adding vents were you described sounds like a good location and will likely get the air out a lot faster.

Jamie Hall

Do not lower

the water line on the new boiler. Doing so can lead to all sorts of interesting -- and usually very obscure -- problems, which you don't need.  Match the new water line with the old one as closely as you can.



You can create a drop header arrangement which will do the job nicely -- looks like you have the room.



Your present header arrangement is not good. What you want to do is come up out of the boiler (does it have one or two risers?) the 28 inches, then 90 over, then 90 down to your new header. Be sure when you pipe the new header that the takeoffs for the steam mains are downstream from any risers (your present arrangement has a bull-headed T, which is a no-no) and the equalizer connection is downstream from the steam main takeoffs (your present equalizer appears to come off from the middle of the header!) -- that way everything is going in the same direction, and you will have much drier steam and a much happier heating system.



The vents can go after the last riser, if you like -- just try to keep them away from an elbow.



The Hartford loop connection should be a close nipple -- but 4" isn't too bad.  But you're going to have a fair amount of new piping anyway (see above) so you can probably change it.



Your connection for the indirect should be OK...

ctjomac

Thanks! What about the return

If you can tell by the pics the 2 returns drop straight down and from what I understand they are suppossed to drop 28" ? Right now they only drop -24" then go horizontal. And the horizontals are only right at the waterline then tee togther and drop again. I THOUGHT they needed to drop 28" minimum.

Rod

28 inch measurement

Hi -The "28 inch measurement" is the required distance between the Boiler waterline (use the new boiler waterline) and the lowest steam bearing pipe. (See attached photo)  You'll also want to check "A" measurement of the lowest steam bearing pipe on the other main. The shortest becomes your "A" measurement and needs to be a minimum of 28 inches.

- Rod

ctjomac

THANKS Rod!...I appreciate

the correct answer. Just wanted to be sure because I don't have that now! Did you see the pic. I tried to take of the vent between 2 90 ells 4" apart with a vent between them? I think it's all original ....That's why I was wondering if I could install them 15-18 inches before the vertical drop to the return, pretty far (20 feet) from the last riser...Thanks Again Rod...joe

Jamie Hall

Well, sorta...

Kindly see my earlier post (below).  You can have a drop header a lot lower than 28" above the boiler water line (I've seen as little as 10 inches) -- provided that you do a drop header!  You do want to go up 28" or more before you elbow over into the drop header, though.



And as I said in that earlier post, whatever else you do, don't mess with the water level.  The new water level must -- repeat MUST -- be within an inch or so of the old one.  Whatever it takes...

ChrisJ

With all due respect to Jamie

and thats a LOT of respect due...



When I installed my boiler I intentionally lowered my water line as much as possible.  I wanted to be sure my condensate would return and then some.

When and if you do change the water line you need to be VERY sure you will not end up with water partially laying in any pipes that were previously full, as in turning a high wet return into a partial dry return and so on. This scenaro is mentioned by Dan in TLAOSH.



I do agree with Jamie in that the safest bet is keeping the NWL the same but I wouldn't completely cross changing it off of the list as long as you are confident in what you are going.

moneypitfeeder

well that's a new one

What do you call an equalizer located in between two risers? A reverse bullhead? Please ask the new installer to locate the equalizer after the risers then dropping to the hartford loop.  

ctjomac

Hi Jamie...I did buy a drop

header kit from Burnham......it was alittle more expensive that way, but less time consuming, espically since I'll be having it done in the middle of winter My main concern (arear of cofusion) is this: Look at the top right and bottom left pics. When the main horizontal ends and drops down 30" or so then it horizontals and tees with the other main then they both drop again....With the new boiler up on 4" blocks I'll be above the water line. I'm changing the returns anyway, because I will be adding vents and I need to know if I should take that 30' drop and make it even more to get below the waterline of the new boiler OR is it ok to still be above the water line until they tee together then drop again? Hope it makes since.

Problem is I've had a few contractors quote the job and got 2 different opinions about the return......Somewhat Lost in Connecticut!

ctjomac

MoneyPit...After reading everything n

here I realized that and bought a drop header kit from Burnham...I think that header was replaced at somepoint....as it seems to have newer pipe, etc. Both supply tappings will be right before the equalizer when the new boiler is installed.....someone did this one wrong!

Jamie Hall

Water levels...

 If one is careful, one can lower the water line in a new install -- provided that one is quite sure that any returns which were wet, stay wet.



And that is exactly the situation with those two drops which then come across horizontal together and go into the main return.  That horizontal run has to stay wet.  If you are repiping anyway -- which it sounds as though you are -- I'd probably take both those vertical drops and run them right down to the floor, then bring them together and run the line back to the base of the Hartford off the leg of the T.  They don't have to go as they do now -- just straight down, then horizontal across and T together, then into the Hartford.



While you're at it, do yourself a favour and put a drain valve down there, at the base of the whole thing.  It might come in handy someday...