Joined on November 26, 2011
Last Post on March 8, 2014
@ March 2, 2014 4:17 PM in noisy slab sytemAn ODR-controlled mixing valve, some hydraulic separation, and perhaps a buffer tank will do the trick.
What is the design day heat loss requirement? How big is the tankless?
@ March 2, 2014 3:32 PM in noisy slab sytemso before you start changing parts, be sure you fully understand what is needed. A heat loss calculation together with the tubing layout (spacing, mostly) will tell you how many GPM at what temperature is required to heat the space. That, combined with the head loss will tell you what pump(s) to use. Your huge ∆T is the result of hot water hitting a cold slab. If the water circulation is constant but the temperature is controlled by ODR, the space will be more comfortable and demand less of the boiler. It can also reduce pumping requirements in many cases.
@ March 2, 2014 2:13 PM in marble tops on radsbut you might want to start a new thread as you clearly have some issues with your system.
@ March 2, 2014 2:05 PM in noisy slab sytemreally, really, really, really prefers constant circulation using ODR.
@ March 2, 2014 2:04 PM in Solar Thermal is Deadmakes sense with a year-round load that requires higher temperatures. Frito-Lay uses it to fry Sun Chips http://tonyseba.com/industrial-scale-solar/sunchips-are-now-made-with-the-sun/
@ March 2, 2014 1:59 PM in Rattling coming from baseboard heating systemin the right places, so we used it! I think we saw a photo here of one like it about a year ago -- could they be the work of the same genius?
@ March 2, 2014 1:42 PM in Trol A Temp Replacement wiringdo you have between the stat and the unit?
@ March 2, 2014 1:40 PM in htp boiler 0-10 signalbecause we run our own PI loops on the controllers, which allows us to dynamically modify them for indoor feedback. I know the DX-9100 supports PI and PID loops, but I've never had a chance to dive in on one.
@ March 2, 2014 10:34 AM in htp boiler 0-10 signalthe 0-10V input does not set a temperature, just a firing rate. The onboard limits for boiler max temp will throttle back at this point if your ODR control has not.
@ March 1, 2014 11:47 AM in Heating-Cooling Loss and Gainis currently working on this, in the form of a radiant heating and solar code.
@ March 1, 2014 11:42 AM in Beating a dead horse.that Jstar and MarkS are tinkering with http://www.midcointernational.com/products/low_nox/
@ February 28, 2014 10:44 PM in Pickup factor. Help me understandClearly written, evidence-based, and entirely useful.
@ February 28, 2014 9:00 PM in I figured out how to calibrate a Pressuretrol!it appears that Honeywell has a serious QC problem (as opposed to an actual design defect.) This could be a good thing.
@ February 28, 2014 8:59 PM in Pressuretrol Issueit appears that Honeywell has a serious QC problem (as opposed to an actual design defect.) This could be a good thing.
@ February 28, 2014 7:40 PM in Pickup factor. Help me understandmodulation and two-stage firing are so wonderful.
@ February 28, 2014 7:38 PM in Howdy folks! And a few questions...to take the bull by the horns. Have you made any envelope improvements? Do you plan to? With -20ºF design temps the ROI should be very attractive.
With existing cast iron radiation, I would lean strongly towards a properly sized and installed fire-tube mod/con running on outdoor reset.
@ February 28, 2014 7:34 PM in Hard Grey buildup in radiant systemof both feed water and exsting system water would be in order.
@ February 28, 2014 7:33 PM in Wiring ALPHA 55 vs.Grundfoss 15-42as mentioned above. These new smart circs prefer constant power, which enables things like auto-exercise to work. We even shut them off for the summer using their onboard menus rather than powering down.
@ February 28, 2014 7:26 PM in Outdoor resetbefore you spend any of your hard-earned cash. Specifically, a room-by-room heat loss calculation and an existing radiation survey. With that information, we can give you much more specific advice.
@ February 28, 2014 12:02 PM in PEX SYSTEMhave the potential to get heated on this -- think Mac versus Windows or VHS versus Betamax.
After using most of the systems out there at one time or another, we settled on ASTM F1960 (aka ProPress, mostly from Uponor.) The combination of larger diameter fittings, the practical impossibility of a "cold joint" (uncrimped in F1807 terms) and the EP fittings' immunity to hard water made the case for us. With Milwaukee selling expander tools, startup costs are minimal and the time per fitting is very attractive. The only gotcha for us is that the brass transition fittings do not tolerate corrosive water like the bronze Viega's and the Uponor stainless fittings are insanely priced. Sioux Chief and Dahl are adding more and more F1960 parts every year, which helps.
@ February 28, 2014 11:49 AM in Newbie Hydronic questionsshould not need anywhere near 150ºF if done properly. I would suggest designing the RFH and then sizing plate radiators to match that if possible. Otherwise, you will need two reset curves.
@ February 28, 2014 11:45 AM in New Gas ConversionThere has been no suggestion of using a conversion burner here.