Joined on June 30, 2004
Last Post on December 9, 2007
@ July 24, 2006 11:25 PM in strange water problembut is there a restriction in the CW line? The Symmons valve is as good as they get with very good factory support. (I had the opposite problem, HW drop-off followed by falsetto soprano singing and simultaneous orb elevation.) Turns out my water filter was getting plugged (HW side only) and the Symmons valve was just doing it's job, balancing to pressure and temperature. Crud will do some blocking too as in my case. If the valve fails to hot I would suspect firstly a cold water blockage then a faulty Symmons valve. But be aware, the Symmons valve is not a true anti-scald valve. If you have scalding temperatures upstream you need a tempering valve anyway or set the temperature lower. The Symmons valve is pressure balanced but turn off one side and what is left on the other will continue to flow albeit less so. Temperature will be the same as enters. Valve can only do so much.
@ July 24, 2006 11:09 PM in Steam System Savings - Without Converting! (Steamhead)Or fill in the (blank) with the ethnic group of your choosing... then go on to tell a really good (engineer) joke.... It's ok. I know how that works... :)
@ July 24, 2006 10:58 PM in Steam or Hot Water .. how to tell ?????Steamhead- Ever feel like the one public works contractor actually using his shovel in the trench while eight of his buddies are looking down in the hole, observing and making comments? Wondered if The Wall was like that for you at times such as this.... p.s.: Who gets to play the cop on detail with doughnut and coffee?
@ July 24, 2006 9:25 PM in Water pressure drop after boiler service?One of the last first things... happens way too often, does it not?
@ July 24, 2006 5:36 AM in Steam or Hot Water .. how to tell ?????I am humbled and flattered by your kind words! Truly and on a number of planes. I try to have fun here, pass on what I can, learn constantly and the best part, sometimes learn that what I thought I knew may not be so.... Thank you so much! Your words made my day well in advance... Brad p.s. The rabbit analogy has basis in fact: I used to breed Dutch rabbits. After segregating them (finally), I came home to the neighborhood children, ages 2 to 8, sitting in a circle, with ALL of my rabbits in the middle. Doing nature's long-term plan shall we say. "Gee, Mr. White. Hope you did not mind... we came over to play with the bunnies...." Arrrrrggggggggh!
@ July 24, 2006 5:26 AM in Why pipe indirect hwh with 1.25\" if fittings are 1\"?Would be acceptable, David. The recent price escalation had me taking that option for the first time. Type L was always my way until now. Slightly better flow characteristics (thinner wall = larger ID). And the cost is a bit less painful. Hot Rod brought up an excellent point on looking at the "system", not just the heater itself. Your drop in capacity means longer warm-up times to temperature, that's all.
@ July 23, 2006 10:37 PM in gas + inexpierenceWhat gets me about condescending and arrogant people who lord their degrees over others is, when it is cold out, whom to they call to get the degrees that really count?
@ July 23, 2006 10:16 PM in Steam or Hot Water .. how to tell ?????As to your question can radiators work with either steam or hot water- the answer is: It depends. If the radiators are the type whose sections are connected top and bottom, they will serve either medium. If connected only across the bottom they are steam-only. If they are dual-medium, keep in mind that if steam now and used for hot water, the capacity drops off by one third (240 BTUH per SF of radiator surface with steam, 150 with hot water at 170 degrees average temperature (180 in/160 out for example). The good news is, if the house has been insulated and improved, this in very general terms can compensate nicely for this loss.
@ July 23, 2006 10:08 PM in Has anyone tried this Primary-Secondary variation?"progressive temperature" sequence of things as Wayne also noted. I would ask if the main circulator should go after the 3-pass and there would be the PONPC. As sketched each circulator is in series to the primary and flows/pressures may differ (not knowing the loads and proportion of each). Also, yes a detail, but the air separator would benefit from being after the 3-pass and before the indirect. The other part of this is the dilution of the heating zone temperature by the indirect load. Can they be in parallel rather than in series? I suppose it is no different than a time-duration deprivation as in any indirect mode, but in this case the return from the indirect goes to the radiators not direct to the boiler. What controls the final temperature to the heating circuit? Will the ModCon be set up to protect the 3-pass? IOW: Fire to maintain 130 F minimum or the 3-pass circulator be locked out until 130 F is reached? Meaning a more positive lock-out I suppose. As so often I do, I may be missing something critical and obvious in what you are doing, so as with Wayne will stand by...
@ July 23, 2006 9:50 PM in Steam or Hot Water .. how to tell ?????It takes a trained eye, experience- and one better be damned correct before proceeding.... :) When one contractor says "steam" and the other side says, "hot water", I smell trouble. The third opinion, "I do not know", did not help either. It may well be hot water -specifically gravity hot water- and have the expansion tank in the attic hence not visible to the naked eye... If the radiators have one pipe connection and a vent about halfway up the opposite side, it is one-pipe steam. If the radiators have two pipe connections, one smaller than the other, it may be two pipe steam. If the pipes are equal in size, more likely it is hot water and gravity hot water as that. (Noted lack of circulator being a give-away). Photos help. But here is better advice: The house is near Baltimore. Steamhead is in Baltimore. Ergo....
@ October 6, 2004 11:55 AM in Small Cottage Developmentin my experience (and only as a check figure as we both know, Hot Rod) would apply only to larger buildings in such a climate. Being detached, the infiltration rate is higher and the external surface envelope is amortized over relatively few square feet of floor area. Four exposures, roof and slab is really a box in space radiating in all directions. The 60-some-odd BTUH per SF may seem high at first. My experience with my parents cottages on Cape Cod have come out similarly when finally heated.
@ October 5, 2004 5:23 PM in Pump sizingThe curve matches the 15 GPM at 5 feet point nicely but drops off rapidly. The 0011 has a very steep curve (high head). My choice would be a Taco 0010 which will deliver 17 GPM at about 8 feet of head, so you have some room in both directions. What I like about Grundfos and others are variable speeds. You can get Grundfos on line, but Taco is a good pump. I think you are all set!
@ October 5, 2004 2:58 PM in Pump sizingWith what you describe it would be hard to detect a meaningful head loss. Would you consider thermostatic radiator valves at the radiators? I am thinking of some way to balance the system based on temperature. Macon makes a nice valve and Tunstall here in MA makes a kit to convert your angle valve to a TRV by replacing the guts. My guess would be that the total head loss would be less than 4 feet, maybe another foot for a TRV, call it 5 feet. A Grundfos 15-58 FC seems suitable on speed 3. (The "FC"=flow check- a good idea where gravity flow probably happens severely). At 5 feet the pump will deliver 15 GPM, not quite the 17 you call for, but pretty good. If water leaves your boiler at 180 F it would return at about 157 F. (22.7 F delta-T). An alternate selection (just to try one) would be a Grundfos UP 26-120 U. This will deliver the 17 gpm at 5 feet of head but has a steep pump curve. It will handle up to 35 feet of head at no flow, and in the middle, 10 gpm at over 20 feet of head. A little difference in flow means a bid difference in head. Stick to the 15-58 FC in my opinion.
@ October 5, 2004 1:08 PM in Pump sizingNo worries on the repeats, Jim No worries on the repeats, Jim :^)> From what you say here, the 170,000 BTUH would require 17 gpm if a 20-degree drop and 8.5 if a 40 degree drop. 40 degrees may be too much for an older cast iron boiler without special controls (water coming back too cool) so we could stick with 17 GPM, maybe 13 if we split the difference. What are the main pipe sizes and would you describe the longest run for me? Not just length but pipe sizes and fitting in each size. Longest run would be from the pump outlet to the farthest radiator and back. By "farthest" means that if the one most distant has a straight shot of piping but one closer has oodles of fittings (oodles is a qualified engineering term meaning "gobs") then the fitting-intensive run wins. Get back to me and let's see where we can take this.
@ October 5, 2004 12:59 PM in Small Cottage DevelopmentThe small heat loss is a challenge. Are you planning on metering the energy? That small btu need may not seem worth it because BTU meters can be expensive for small amounts. Heresy Alert!: Purely from a development view and tenant responsibility you might do an economic payback of electric resistance heat. For 20K BTU's that is about 6 kW. Expensive sure, but the tenant pays and a lower first cost. Due diligence says to suggest it, then market hot water telling the tenants how much they will save in utilities. A base of comparison at least. The central HW system approach seems intelligent; the space required to support all say five cottages would rival the space needed for one. Transporting heat via the outdoors or in a common chaseway is a challenge. For boilers, a Monitor MZ, Munchkin, others, all have application here. But think antifreeze, like Noble No-Burst. The heat loss per works out to 62.5 BTUH per SF which seems reasonable for small area stand-alone buildings with a 0F to single digit design outdoor temperature. (It would seem high for larger buildings even if little insulation.) Infiltration is your biggest component even and especially if you have good floor wall and roof insulation. But the high BTU/SF load may allow only about half of that required heat to be provided via the floor. If you figure maybe 35 BTUH per SF as the most for a comfortable floor, then subtract any unusable area, you may get to 10,000 of the 20,000 required. You could use Climate Panels in the floor and then up the walls to a point to make up the deficit. Too high up and tenants want to hang pictures? Well, that gives me the willies too. I'd say no to that. I would put in a good radiant panel radiator such as by Runtal, Burnham, Buderus. High density, radiant effect and can take advantage of low water temperatures (thinking condensing gas boilers here). In the alternate, a blower coil such as by Burnham (wall or kickspace) can be sized for lower water temperatures and not take up much space. Not sure about the CombiCore. Even though it is of my namesake company (Bradford White by coincidence only) I have heard mixed reviews. Other I am sure would fill you in. Just my two-cents. Looking forward to learning more.
@ October 5, 2004 12:39 PM in How to Measure Headis very forgiving. Nice pump and you will like the color probably. Wayne is right.
@ October 5, 2004 12:37 PM in insulating undergroungd steam returns?with expansion and contraction gravel (crushed stone) will shred any insulation if not the pipe itself. I would suggest insulating in fiberglass, at least an inch thick, then sliding a piece of SCH 40 PVC pipe over the buried portion. Seal the ends with spray foam and paint for UV protection. Just a thought.
@ October 5, 2004 12:34 PM in Pump sizingI would need the boiler nameplate rating (fuel input, BTU output both gross and net "I=B=R" ratings and burner rating (gph)if oil or BTU's per Hour if gas. From there it can be determined the maximum amount of heat to be delivered in BTU's per hour. And from that we can establish a flow rate which normally but not always is based on a 20-degree temperature drop (BTU's per hour divided by 10,000) or a larger temperature drop which would dictate less flow. The amount of pressure required is another matter, but if the pipe sizes are large (older steam pipes) the pressure requirements tend to be quite low in my experience. Each job is different! Without knowing radiator and pipe sizes, the above is probably the best place to start.
@ October 4, 2004 8:13 AM in Wetstockgot me thinking that Ed Nordstrom of Viessmann (in nearby Warwick) has a couple of guest slots as does at least one other gentleman I do not know. WHAT IF... some of us agree to sponsor some of the neophytes and others Tim mentions, defray the cost or outright sponsorship of a new person. Ideal: everyone bring and sponsor a guest, but if impractical, chip in 1/4 or 1/2 the cost and get a 1:4 or 1:2 ratio. I am pledging the cost of a place at Wetstock if someone matches me. Call this a challenge grant! Anybody?
@ October 4, 2004 8:04 AM in TRV with bypass?re-read your voltage and hence circulator cost (mentioned in my post reply to Larry). You must be living off the grid! See the Larry post and my added comments and see if that makes sense. It all gets down to flow, delta-T and radiator size. In the end, an electric heater, but I can hear you say "no" from here. :^)>
@ October 4, 2004 8:01 AM in TRV with bypass?in that if one zone you are only limited to available flow and delta-T (but in a larger sense, aren't we all?. But as he states, the panel would be quite large and deep, maybe a Runtal-style convector? Even if low temperature, if you could squeeze in another zone (which you stated was impractical, Brad) the lower head would allow for a $60 circulator versus the $200 model.