Heating Help

Can/Will the 260 control my damper correctly as well?

@ December 15, 2006 7:22 PM in Tekmar 256 versus 260

> I dont know if the indoor sensor will gain you a
> lot, but just for the cost of a relay, you should
> upgrade to the 260. Also if you decide to add
> dhw to your boiler, you have the option right
> there.
>
> I think you are correct to be leaning
> toward the 260.

Basically, my current "legacy" controls are doing three things: 1) fires boiler to set output temp 2) turns on circulator pump 3) open/closes damper accordingly I know the 260 will do 1 & 2, but will it also perform the function for #3? Thanks Al

Good idea!

@ December 15, 2006 6:03 PM in How does paint or enclosures affect radiator efficiency?

I think I'll actually do three tests: 1) with cover 2) without cover 3) with cover, but top open(simulating a perforated top) Good idea =)

@ December 15, 2006 3:59 PM in OK, a couple more \"dumb\" questions about my old gravity system

I gotcha, it is "on the ASAP list". Technically I do HAVE one, but it is a 150psi/210degree type you would typically find on a water heater. I need a 30 psi relief, and am trying to source one as the local big box doesn't carry those. Al

Tekmar 256 versus 260 - best application?

@ December 15, 2006 3:30 PM in Tekmar 256 versus 260

Based on some recommendations here, I have been researching the Tekmar 256 and 260 boiler controls to retrofit to my ca1991 gas hot water boiler. I do not have Domestic How Water plumbed through my boiler, so although the 260 provides that function, I don't need it. So, that might seem to indicate using the 256 alone, but it seems like the 260 is a more complete control, and also controls a circulator pump, which I do have on my system. If I used the 260 instead of the 256 combined with my existing old controls, it might be a simpler/cleaner installation. The 260 is about $100 more than the 256, but if my interpretation of the controls is correct, I could eliminate my old electromechanical based controls by using the 260, instead of piggybacking the 256. But other than simplifying the system by not having two controls working together if I used the 256, I don't know if anything else the 260 offers might make sense to install it and spend that $100. Hence my post looking for thoughts and others experiences. One other advantage the 260 may have is its ability to use an internal temp sensor to also regulate temps. But my question would be how useful is this if one already has a quality thermostat sending demand? Would they work together, or "compete" in regulating demand and output water temp? What do you think? Would it make sense to "simplify" the contols for the system and do away with my old controls and just spend another $100 to get the 260, or would the 256 really be sufficient? I have attached a photo of my current boiler, and the electromechanical controls currently attached. Thanks! Al

Where does the Tekmar 256 place its boiler water ouput sensor?

@ December 15, 2006 3:17 PM in outdoor reset savings report

That's excellent. One question, I was reading the installation notes for the 256, and it looks like it piggybacks onto my existing boiler controls versus replacing them... which is fine if true. But it obviously has a boiler sensor to measure the output water. My current electomechanical boiler controls hang directly off of the out boiler output piping to sense the water temp. The online install documents for the Tekmar don't show how their water temp sensor is attached. So I am wondering if you know if their sensor needs to be directly piped into the boiler output water flow(which would require a new fitting for me to install), or if it simply attaches to the outside of the pipe? The install docs aren't clear, and I don't have a photo of the sensor itself(they call it an 071 Boil Sensor). Thanks Al

@ December 15, 2006 2:37 PM in outdoor reset savings report

It's a shame(sortof statistically speaking) that more than one "variable" changed in this scenario, as I'd really like to know how much the Tekmar helped. I am looking into installing a Tekmar(256, I don't have integrated household hot water) myself after a recommendation here and am just very curious about the potential positive impact of that alone. But that's very cool to hear about a 20%+ savings overall indeed. If anyone has any other stats on just installing a Tekmar, that would be great to hear about as well. Al

Just curious in general about efficacy of any stop leak product

@ December 15, 2006 2:32 PM in Leak in floor radiant - Will boiler \"stop leak\" work?

I don't know the answer to your question, although I am very curious to hear about any replies regarding the use of "stop leak" products on hot water systems. I currently don't have any leaks, but I have wondered if it might be a good preventive measure on older systems like mine(~80 years) where a lot of piping is in unseen areas to run some sort of stop leak through the system every few years to stop any pinholes or other seeps from getting worse *shrug* Al

How does paint or enclosures affect radiator efficiency?

@ December 15, 2006 2:19 PM in How does paint or enclosures affect radiator efficiency?

I have two general questions about paint on radiators, and radiator covers, and how they affect heating efficiency. My 80-ish year old hot water radiators have 2 or three relatively thin coats of paint on them a this point. I'd say the paint at its worst is maybe 1/64 or 1/32 inch thick, and most places thinner. In fact, for most portions of each radiator(inside past the first "fins"), they seem to just have their first coat of old green paint. My first question is: How much does paint on a radiator affect heat transfer? Should I worry about trying to strip off the paint at some point to increase efficiency? Should radiators(mine are cast iron) have at least one coat at all? I also have original sheet steel radiator covers for all my my radiators, except for the pantry and under the kithen sink. They are fully enclosed, except the front panel is perforated steel with holes in the lower portion and vertical slats at the top, and have a hinged top lid that accomdates filling a water/humidifier tray. I have attached two photos of my covers. I am wondering if these covers are purely decorative, or if they help or reduce actual heating efficiency. Thanks Al

It ain't broke, but I think it may be working too hard.... =)

@ December 15, 2006 1:28 PM in OK, a couple more \"dumb\" questions about my old gravity system

Hi Tim, Reasonable questions.... let's see if I can answer them as directly as possible. The system apparently has heated "well enough" over the last 15 years since the conversion for no one to feel enough pain to look into whether the system is currently engineered correctly. It was originally installed in 1929 as what I believe to be an overhead gravity system. It seems to heat pretty evenly in its current configuration, and the cycles don't seem too short, but I really don't have anything to benchmark it against right now. I suppose once the weather becomes consistently cold(we are in Sanford, NC, near Raleigh), and we move upstairs out of the basement(renovations have us living down here) I can time the cycles and see how many times it cycles per hour. I do know that my new electronic thermostat has it defaulted to expecting cycling every 20-30 minutes. But again, I don't know if that is reasonable?? Also, my circulator pump only runs while the boiler is firing and I have one loop, no bypass of any kind, if that is helpful information. But since purchasing the house in March of last year, this is our first Winter in the house, and I have been taking the time to investigate and learn about its current state. This interest was driven by several observations: 1) Some radiators do not heat well(which could be from several causes such as a broken valve or air, which I am also investigating) 2) Past $500/mo heating bills in Jan/Feb (gas fired ca1991 80% eff boiler, 2 story 4000 sqft, 1929 house with about 65 windows, but well insulated for its time, even in walls and 12 inch thick brick on first story) 3) Obvious other oversights in the conversion such as no pressure relief valve, no system air vent, etc So I am trying to learn enough about the system to help inform the heating folks around here, because none seem to have an boiler/steam expertise anymore beyond basic repair. For example none seem to have the expertise to know what a gravity system really was/did, and if it is currently circulating correctly. What I'd like to do is learn how it should be configured, so I can make educated recommendations. Then I'd like to feel confident that the sytem is running as effectively and efficiently as possible, and right now a $500 heating bill and some of the other questions make me wonder if there may not be a little more of both that can be squeezed out of the system. Plus, I like to solve "mysteries" and understand the systems of my house =) Prior to this, no previous owner I talked to, or local HVAC/mechanical folks had any clue how the system was supposed to work or be maintained. Thanks in advance for any help and suggestions. Cheers Al

OK, a couple more \"dumb\" questions about my old gravity system

@ December 14, 2006 1:42 AM in OK, a couple more \"dumb\" questions about my old gravity system

I apologize in advance for continuing to put you all through these 20 questions that probably seem pretty basic... but I think I've got it narrowed down to two final questions to confirm what I(and you all) think. That my system is an overhead gravity system, currently running in "reverse" after being converted to a closed circulator system about 15 years ago. Well, I have the original blueprints, although over 80+ years, some of the legend and other notes are gone from the margins. So one still can't call this the Rosetta stone of my system. But, there are still some clues. And this is where my final two really dumb sounding questions come into play, so bear with me. Although on the blueprints, there are arrows on the piping diagram, believe it or not, there are a couple places where the arrows are in conflict on the same pipe. So I think that may have been an error on the part of the architect/engineer. But... 1) There is one main line that runs from the boiler all the way to the attic, called the "main riser". Now, based upon this name, I would like to assume it means exactly what it is called, and if so, would have been the original supply side of the system. So question #1: Is it safe to interpret "main riser" as being the original "main supply riser" of the system? 2) There are several pipes labeled as "return" lines. I would like to assume these too mean exactly what they are called. So question #2: Is it safe to interpret lines labelled as "return" as lines that actually were intended to "return" the cooler water back to the boiler? Now, if the answer is "yes" to both of these, then I indeed seem to have an overhead gravity hot water system, that has the radiator control valves on the output/return(bottom) side of the radiator, and is currently circulating backwards following its conversion to a closed circulating system around 1991. If I can confirm this as seeming to sound reasonably correct from all of you, I would then like to describe again my current setup, and see if I can get some opinions on why they may have plumbed this backwards, and if it would be a good idea to make some changes now. But I'll save that for another thread following your feedback on my two questions =) Thanks! Al

@ December 13, 2006 1:37 PM in What is the correct temp setting for a hot water boiler?

Unfortunately I don't know enough about this to understand the Primary, Secondary, decoupled comments.... but this is a cast iron boiler. The circulator pump only runs when the boiler is on. Is this best? Should it circulate at time without the boiler on? I don't have any kind of bypass loop, so I have one ciculator, and the return and output are the only connections into and out of the boiler into ths sytem. I am very interested in this Tekmar device though. Is this something one can "do it yourself" if typically handy with most construction, plumbing, and electrical? Thanks Al

@ December 13, 2006 1:33 PM in Gravity Hot Water Conversion Done Right?

Well I ordered some bleeders, for only about $2 a piece! Heh, with every other part of my home renovation, especially plumbing and electrical parts costing much more than that regardless of size... that was pleasant surprise. So, I have two opinions on the system coming. There are no "pros" listed here within 100 miles, but I found two middle aged guys that used to work on boilers earlier in their carreers up north. The first came by today, and knew his boilers, but I don't think he really knew or understood the different types of gravity systems. Based on my research I am convinced that I have an overhead gravity system, hence my prior comments about it currently being plumbed/circulated backwards from its original convection induced direction. But his comment was that the supply valve on the radiator would identify the correct original direction, and he seemed quite convinced by this. I would tend to agree that ideally the valve on the radiator should be on the supply side, but they are all on the bottom of my radiators, and that would have been the return if this was indeed an overhead system by the way it is plumbed. One person on this thread had commented that the location of the valve is irrelevant, but I'd love to hear additional comments/theories on this. Also any additional thoughts on whether an overhead gravity system should have been "reversed" is a good idea when converting it to a closed circulator system. Also, one last question... other than the 4" express riser, overhead piping in the attic, and my one return(now acting as a supply) line, are there any other telltale signs that I can look for to positively identify which pipes used to be the supply and return originally? One thing I did notice on reading more of Don's book, is that on overhead gravity systems, they often used special fittings to divert water into the radiators as the water came down from the mains. I can't be certain as I can't see all the piping, but I don't think I have anything other than plain Tees off of the lines coming down from the overhead mains. But I do have access to at least one, and it looks like a regular Tee, except stamped on it is a W or M with a circle around it. Does this mean anything, perhaps a Monoflow fitting? If so, this would be another clue perhaps confirming this is an overhead gravity system that is using reversed flow now. Thanks. Al

Tekmar questions

@ December 12, 2006 2:25 PM in What is the correct temp setting for a hot water boiler?

So, will this interact or interfere with my indoor programmable thermostat? Or are they independent functions? Also, would this completely replace my current Honeywell boiler controls that also controls the circulator pump, or does this just piggyback onto the existing boiler control module? Thanks Al

What is the correct temp setting for a hot water boiler?

@ December 12, 2006 12:58 PM in What is the correct temp setting for a hot water boiler?

Per my earlier post about a gravity hot water conversion to a sealed circulated system.... I have another question about the correct temperature setting for boiler itself. I have read that around 180 degrees may be a typical setting for the boiler control, but during my investigations into this system, I noticed that they had it set at 200 degrees. I have also seen recommendations anywhere from 165-180 as a typical setting. So my question: What is a normal boiler control temperature setting for a circulated hot water system? I'm sure that the prior 200 degree setting must have contributed somewhat to their $500 a month heating bill! Thanks Al

@ December 11, 2006 4:18 PM in Gravity Hot Water Conversion Done Right?

.... except that the system is now running in reverse from its original design, plus at least one radiator only has inlet/outlets on the bottom, so I think I may have some air in a few of them. Although the system should vent itself, I think I would feel better if I had the ability to bleed them if needed. Now I just have to find some =) Al

No Pros listed even within 100 miles =(

@ December 11, 2006 12:20 PM in Gravity Hot Water Conversion Done Right?

Well, I did the "Find a Pro" search, even out to 100 miles, and there wasn't anyone listed. So I guess I just need to call around. I am in Sanford, NC, right between Fayetteville and Raleigh. Al

Thanks - where to get air bleeder valves?

@ December 11, 2006 12:12 PM in Gravity Hot Water Conversion Done Right?

Thanks everyone. The circulator(output) definitely pumps toward the expansion tank at this point. It pumps into the "cold" supply side(FROM the old riser) going into the boiler, then as the heated water leaves the boiler, it goes into the now supply line(which was the return), to which the expansion tank and water make up supply is connected. BTW, I have no pressure relief valve or working pressure gauges in the system at all, so I'm going to have to add that as well. I just put a new air bleed valve up in the attic. A previous owner couldn't figure out that they had painted over the drip vent line in the eave, and to get the system drained and bled, they just removed it and threw it on the attic floor beside the discarded old expansion tank then closed the old valve to the original expansion tank line *sigh* I've put a new #79 vent on, and added a manual air inlet valve for speedy draining of the system. Now I just need to figure out this whole conversion and if it was done right. And it sounds like everything has confirmed my initial suspicions of an overhead gravity system. Which in general should be good news from what I have read. The system does heat, as it has done since the last 15 years, but I suspect it could be better as several of you have suggested as well. BTW, I just went and looked at the original blueprints for the house, and my earlier interpretation that 3 of the radiators were being fed by "one pipe" was thankfully incorrect. It just appeared that way due to how the pipes ran in the basement, and then disappeared into the brickwork. Everything feeds from the main line up in the attic, which now again is acting as the return. But this was all very helpful, and I realize I'll have to try to find a pro that can come out and really evaluate the system. But this all helped. I am learning tons about the system, which is great. Where before, it was all a mystery. BTW, would it make sense to go ahead and install some air bleeders on some of the more "pesky" radiators that may have some trapped air? If so, where can I get these? I can't seem to find them online anywhere. Thanks again. Al

Gravity Hot Water Conversion Done Right?

@ December 11, 2006 12:02 AM in Gravity Hot Water Conversion Done Right?

I have a 1929 vintage gravity hot water heating system, that had a new boiler installed and converted to a circulated system around 1991. I have no air bleeder vents in any of the radiators, and they all look original. I have a lot of questions about how they seemed to have plumbed the system and how it was converted as I read and learn about such conversions, but have some basic ones I am curious about first to help identify which sort of system I have. After reading excerpts from Dan Holohan's book, I really think I have an overhead gravity system. First of all, is it safe to assume that a cut-off valve on a radiator indicates it is the hot water "supply" side? All of my radiators have their original valves, and I was curious if this always indicates the input side of the hot water? If so, this may answer some questions, or make it more confusing. To that point, all of my radiators have the supply valve attached to the lower fitting. Most of my radiators have the lower fitting and upper fitting on opposite sides, while a small number have them on the same side(still with valve on bottom), and one has the supply and outlet on opposite sides, but both on the bottom of the radiator. I ask because my system appears to be an overhead system in some respects due to the huge riser that goes up to the attic, but all my supply valves are connected to what then would have been the return line to the boiler, not the line coming down from the overhead. Is that normal or possible with an overhead gravity system? That is, can the individual radiator valves for a radiator that fills from the top have its valve attached to the bottom fitting? Regardless of being an overhead or upfeed system I know this is how three of my radiators are plumbed, as they only have one pipe going to them, and the radiators for these units are fed from through their bottom fitting. I have to guess the cold water returned in the same pipe. In its current ca1991 configuration, the circulator pump is now pumping into the boiler on the "cold" side pulling from what appears to be the old riser, and after exiting the boiler is circulating into what I think was the old return line. However, again, this line connects to all the radiator valves, so I don't know. But, if this is a correct assumption, here is my big observation/question: The ca1991 system now pumps water backwards in the system from the direction it would have circulated by gravity. Is this correct? I am also concerned that I have the correct ciculator for this application. The circulator I have came with the boiler, and is a a small, high-speed, wet-rotor circulator versus something like Bell & Gossett Series 100 that is recommended in Dan's book. The circulator on my boiler is a Grundfos UP15-42F. Is this a good application for a gravity conversion, or should I look for something more like the B&G cited above? I have no idea who did the conversion 15 years ago, and I don't have a good source here to ask(I am in Sanford, NC). But I worry that the conversion may have cost a lot of efficiency, since previous owners have cited $500 heating bills on the worst months to heat the house(4000sqft) at 65 degrees. That seems a bit high, plus I have three radiators that just don't heat well, so I wonder if the conversion has made it work inefficiently. Apologies for the rambling questions, but I'm just getting started at understanding my system, and how it could be made to work better. BTW, the boiler is a Dunkirk PWB-8D rebadged as a Carrier unit. Thanks Al