Joined on November 26, 2011
Last Post on December 4, 2013
@ September 29, 2012 11:56 PM in TT Prestige 110 pump wiring questionUntil you have that sensor working. 70' of wire is not an issue at all. Take the winter to tinker with your reset curve - when you get it set right, pumps will be running nearly 24 hours a day.
Then it's time to take a look at your pumping costs and decide if it's worth modernizing there.
@ September 29, 2012 11:53 PM in Getting butt chewed for this. Sould I?what flow do you need and, why won't the TT HX deliver it?
@ September 29, 2012 11:51 PM in New Boiler, and Problemshttp://www.heatinghelp.com/forum-thread/100691/Running-boiler-with-Rhomar-Hydrosolv-9150
@ September 29, 2012 2:20 PM in TT Prestige 110 pump wiring question...in an appropriate location and the ODR curve properly set? I've seen an unfortunate number of these "installed" without bothering to do so.
@ September 29, 2012 12:59 PM in NG fired steam boiler recommendationThanks - that brought up the brochure but I still can't figure out how you actually got there - they really did hide it.
I'll call Smith on Monday and see if they can provide model numbers and an IOM.
If this proves too rich for his blood, what would the next best choice be? Steamhead?
@ September 29, 2012 12:47 PM in Your thoughts about splicing 3/8" pex?
- ASTM F 1807: Specification for Metal Insert Fittings Employing a
Copper Crimp Ring. These fittings are intended to be used in 100
psi cold and hot water systems up to 180*F. Requirements for
materials, dimensions, and markings used on the fittings are also
included in this specification.
- ASTM F 1960: Specification for Cold Expansion Fittings with PEX
Reinforced Rings. The same standards apply to these fittings as F
- ASTM F 2159: Standards Specification for Plastic Insert
Fittings Employing a Copper Crimp Ring. These standards establish
requirements for sulfone plastic insert fittings and copper crimp
rings for PEX tubing. All other standards are the same as F 1807.
- ASTM F 2080: Standards Specification for Cold-Expansion
Fittings with Metal Compression-Sleeves. These fittings and metal
compression sleeves are intended to be used in residential and
commercial, hot and cold, potable water distribution systems. All
other standards are the same as F 1807.
@ September 29, 2012 12:36 PM in Aluminum Radiant Floor PanelNot quite sure what you're looking for here -- where would the tubing g? Above the plate? Below the plate? Either way you have to put it somewhere.
Is the concrete poured on grade? If so, you're going to want some insulation between the tubing and the slab. http://www.roth-usa.com/products_radiant_panelsystem.cfm is the best solution I know of for this application.
@ September 28, 2012 12:37 PM in NG fired steam boiler recommendationThanks - I'll look into that.
I have a CA and will probably do the final setup.
Edit: No mention of gas in the IOM - is there any documentation on this option?
@ September 27, 2012 10:19 PM in Boiler System ReplacementLochinvar is big -- very big. Immense would probably be more appropriate at this point. They have a long history (for an American company) with condensing boilers across a wide range of sizes. Until quite recently, they (like many other brands you might recognize) built their mod/con boilers around a heat exchanger manufactured by a French company called Giannoni. As long as these were properly installed and maintained, they provided impressive efficiency. The design was what we call a water-tube: Passages in the stainless steel carried water and the gas burner operated in an open chamber at the middle of the spiral. These passages were rather narrow, and did not like hard water. Most of the western US continent has hard water.
Another company called Triangle Tube (which is part of the Belgian ACV group) introduced a condensing boiler a few years back based on a new fire-tube heat exchanger. In this design, the 'tubes' in the heat exchanger carry combustion heat through a vessel which contains water. The design is far more tolerant of hard water, has significantly less restriction on the water side of the HX, is impacted less by the byproducts of natural gas combustion, and has less risk of flash boiling. They also used a different stainless alloy (439) which proved more resistant to natural gas condensate and chlorides than the typical 316L alloys used by most other manufacturers. The combination of these features took Triangle Tube from relative obscurity to a significant percentage of the North American condensing boiler market in just a few years.
Thanks to a series of events which are not particularly relevant here, that heat exchanger is now being used in several manufacturers' boilers which formerly used Giannoni or other (sometimes aluminum) heat exchangers. There's a reason they all jumped on this the moment it became available.
Lochinvar is one of those manufacturers. The WHN models are in a different league than the earlier Giannoni-based designs. Lochinvar's controls are excellent, and when paired with the superior fire-tube heat exchanger design, they make something I can comfortably recommend. If the boiler proposed is not a WHN, please ask your contractor to bid a WHN-based system. The low head loss of their fire-tube heat exchanger allows the vast majority of residential systems to be direct pumped. This saves money up front (one less circulator to buy plus lower materials and labor costs for your near-boiler piping) and additionally lowers operational expenses (only one pump to power.)
Triangle Tube now has an improved version of the fire-tube heat exchanger and some spiffy new controls to go with it. They're a pretty smart company and I suspect they might have another home run on their hands. Time will tell. Meanwhile, the old (proven) heat exchanger is available in a whole lot more boilers and seems to be taking over the market quite nicely.
Most of the bad press on condensing boilers is attributable to either bad designs (especially early aluminum heat exchangers), poor installation, or lack of maintenance (water-tube heat exchangers require regular maintenance which few actually get.) Like all boilers, whatever their construction, the fire-tube heat exchangers should have an annual inspection and cleaning. Similarly to cast iron boilers, the fire-tube designs are fairly tolerant of knuckleheads: if you ignore them for a decade, more than half will probably survive. The same can not be said for most water-tube designs.
@ September 27, 2012 4:49 PM in Test question from today:It's a bad question.
They're unfortunately common on licensing exams...
@ September 27, 2012 4:40 PM in NG fired steam boiler recommendationDon't have that just yet, but I suspect based on the size of the building and the age that we're looking at something in the 300-500 sq ft range.
@ September 27, 2012 11:49 AM in NG fired steam boiler recommendationA friend needs to replace his existing steam boiler and while we unfortunately have no real steam pros in the area, I do know one greybeard plumber that has done enough steam and will actually follow a manual. Homeowner has a copy of We Got Steam Heat (thanks, Dan) and I will be reviewing the proposed piping and sizing with him before he signs a contract.
A 3-pass with a gas conversion would be great, but the plumber is not familiar with them and I think that's probably asking too much at this point, so I'd like to recommend something that can be bought as a package. What say the pros?
@ September 27, 2012 10:33 AM in Oil to Gas conversion - doing the math!Begin at the beginning - what is your estimated heat loss now? What is the estimated heat loss after the walls are insulated? For a climate like Boston, insulation is almost certainly going to give you the highest ROI and should be done either before or along with the boiler replacement. It's the "gift that keeps on giving" and will keep paying back year after year over the entire life of the structure. It will also reduce your cooling load in the summer, so if it's at all affordable, just do it.
Carl has this spot on and you should heed his advice. A properly installed mod/con will save significant amounts of fuel. I also prefer (strongly) fire tube HX designs and would recommend you ask your contractor to install a properly sized "smart" circulator with the boiler.
@ September 26, 2012 12:55 PM in Boiler System ReplacementInsulation is your best investment - ROI can be 25% or better in many cases. Once you insulate, the temperature required for design day heating will be lower than it was before. This plus an outdoor reset curve should allow the mod/con to condense much of the time while offering superior comfort. Any mathematical comparison would require a lot more info and would still involve some guessing. You can probably count on at least 25% if there's no mixing valve-based ODR or buffer tank on the conventional boiler.
I'm not a big fan of their earlier mod/cons, but the Lochinvar WHN is a fantastic boiler. It (or a similar fire-tube design) can be direct pumped, which will simplify the system piping and reduce both first cost and operational expenses for pumping.
@ September 25, 2012 8:55 PM in Boiler System ReplacementEquipment load sizing is almost certainly a whole building heat loss. This needs to be broken down room by room in order to properly size emitters - or to determine what fluid temp will satisfy the demand for a given emitter in a given room, and if any of those rooms have improperly sized emitters.
As to the savings potential, the difference between an 84% conventional boiler and a 95% mod/con will be much more than the 11% difference on the nameplates. Unless the conventional boiler has a motorized mixing valve controlled by outdoor reset and sufficient water volume (in the boiler and possibly a buffer tank) to eliminate short-cycling during shoulder seasons, the net annual fuel savings from the properly installed mod/con could end up in the range of 22-33% in many cases.
If your boiler is 65% and the new insulation can get your fluid temp at design conditions down to something like 130F, you could see a much larger reduction in annual fuel usage.
@ September 25, 2012 7:17 PM in Boiler System ReplacementMeasuring baseboard is only part of the story. Has someone actually done a proper room by room heat loss calc? You'll need to know the existing structure losses as well as projected numbers after your insulation upgrade.
Fuel savings from a properly installed mod/con usually end up more like 2-3x the nameplate efficiency difference when compared with a conventional non-modulating boiler. There's also a difference in comfort that comes from properly controlled distribution temps using outdoor reset - you can get this from a conventional boiler, but it requires additional controls, labor, and piping that mostly negate any initial cost savings.
@ September 24, 2012 11:04 AM in delta t vs delta p circulator controlI'm pretty sure Taco has all those options in the BumbleBee. Too bad they only offer it with 007 hydraulics.
@ September 24, 2012 10:58 AM in Radiant Heat QuestionsThe goal is even heat across the floor surface. For a given average temperature, tubing on wider centers will require a higher fluid temp, which makes for hotter hot spots (hot stripes, really.) Smaller tubing on narrower centers will give more even heat and do so using a lower fluid temperature, which will increase boiler efficiency (on a mod/con) or allow more weeks of active solar heating in that application. Too small and pipe friction becomes a problem - 3/8" and 1/2" work quite well.
Proper use of extruded aluminum plates (or the new graphite ones) will further increase transmission efficiency by about 75%.
@ September 22, 2012 5:18 PM in Radiant Heat QuestionsI suspect an overwhelming majority of radiant professionals would consider the advice offered on that site as borderline mechanical malpractice.
The physics are not all that complex, but there are still an unfortunate number of manufacturers, dealers, and installers out there who either have not bothered to learn them or simply they they don't matter. Caveat emptor.
@ September 22, 2012 5:02 PM in Radiant heat without a buffer tankIs there a heat pump involved here?
@ September 21, 2012 8:35 PM in delta t vs delta p circulator controlDelta-P (or delta-PV) control is tailor-made for distribution loops with multiple zone valves, whether or not the valves themselves are are proportional.
Delta-T is ideal for single HX loops that do not have control valves (changing flow) in them. Boiler primary loops are a prime candidate here.