Joined on October 29, 2003
Last Post on October 30, 2008
@ May 31, 2008 11:54 PM in Beckett Heatmanager vs. TekmarThe Intellicon HW and its less sophisticated sibling the Heat Manager adjusts the burner run pattern to match the system’s “heat load.” Its action is similar to the industry-accepted method of “outdoor-air temperature reset control,” the tekmar 260, but does not require an outdoor-air temperature sensor or the need to profile the building in order to adjust the “reset” controller properly. IntelliCon-HW+ determines the “heat load” by using a temperature sensor that monitors the boiler’s out-flow water temperature and the rate that this temperature is changing. Since the Intellicon HW+ can be installed by most do it your selfers and does not require any tuning after installation its payback is significantly shorter then the tekmar since the tekmar usally requires professional installtion at $1000 as opposed to the Intellicon which can be purchased on-line for less then a quarter of the price....
@ March 22, 2008 10:34 AM in Mod-cons in summer conditionswhere you would use an indirect instead of a reverse indirect? For example, if you need a high GPM for a short time period, aren't you better off with the large reserve of a conventional indirect? Or are you saying that even in that case you are better off with a reverse indirect?
@ March 21, 2008 3:36 PM in steam and indirect hot waterI piped it according to the manufacturer's instructions plus a couple of extra valves. I oversized the pipe. I used a bronze pump with a wye cleanout right before it. The extra valves came in handy to purge the air on startup. Basically it goes out of the boiler, drops to the floor, goes through the wye, through the pump up into a check valve, through the indirect, drops back down, through another checkvalve and up into the boiler. There are boiler drains and cutoffs everywhere. The oil company suggested leaving temperature on the boiler during the summer, and it comes on and off maintaining its temperature even in he summer many times a day. The indirect pump also comes on many times a day to maintain temperature of the hot water. There are more efficient ways to control it but this way was simple. Efficiency/savings is a tricky calculation because with the new indirect, my family takes longer showers using higher flow, so any savings are lost due to increased usage. A thermostatic mixing valve maintains a constant temp regardless of the inputs, so there is no seasonal adjustment needed. Yes, you don't need a big tank if you can recover it fast enough.
@ March 21, 2008 9:22 AM in steam and indirect hot waterI have a steam boiler with an indirect. Works great. The size of the boiler does affect the size of the tank that is optimal. A big indirect on a small boiler will give a larger hot water reserve, but it won't recover very fast and it may make more sense to just use a smaller indirect on the smaller boiler. You usually size for either the total radiation and you don't add in the DHW demand. This is because you don't need DHW 24/7. The only downside is that if on the coldest day of the year you leave the hot water running, the house won't get warm enough. The indirect water temperature might or might not be higher than the needed temperature depending on how you set the aquastat. If you set it higher than needed (in order to be able to supply more hot water), then you need a mixing valve on it. You wouldn't need to adjust this seasonally.
@ March 21, 2008 9:09 AM in Mod-cons in summer conditionsreverse indirects to regular indirects? Are you suggesting that reverse indirects are always better? Is there a limiting situation where you would prefer a conventional indirect to a reverse indirect? When you say you only need 10 degrees above discharge, how many GPM is that supplying for what size tank?
@ November 13, 2007 7:39 PM in Gravity hot water recirq pipingWhy does the return loop need to be more than 1/2? Thanks, Tim
@ November 9, 2007 10:25 PM in Radiant Heat System - Loop QuestionAre you suggesting radiant ceilings? Radiant walls? And I thought the idea was to put the heat on the outside walls where the dead men put radiators. Please explain.
@ September 5, 2007 2:02 PM in nuisance pilot-light outagesWell, the vaporstat didn't solve the problem, but I'm glad I got it on there anyway. I got the guy who installed the boiler coming out to take a look. Thanks for all your suggestions, I printed them, hopefully they'll help if he can't figure it out. I'll let you know how we solve it, if we do.
@ May 2, 2007 9:10 AM in Has anyone installed the Roth Radiant Panel product?Did you make those aluminum transfer plates in the last two pictures? If not, who makes them? Thanks, Tim
@ April 19, 2007 5:14 PM in One pipe boiler sizingThe sizing should be based on the EDR. Your intuition is correct, it is a mistake to oversize the boiler. I recommend the book The Lost Art of Steam Heating, sold on this site. It explains exactly how to do it and it is a fun read, and it will save you a lot of money by showing you the right way to do things related to steam heat.
@ April 4, 2007 12:52 PM in zone valves vs constant circulationI looked at their literature and spoke with their rep today. If the product works as claimed, this looks like a good solution. Thanks for pointing it out.
@ April 4, 2007 12:47 PM in zone valves vs constant circulationAs I understand it, using lower temperature water to produce the same amount of heat takes less fuel for the boiler. Additionally, providing more even heat decreases the likelihood of the user raising the thermostat. But running the circulator more obviously takes more electricity. Are you saying that the circulator eats up more than can be saved by the lower temperature and evener heat?
@ April 3, 2007 11:21 AM in zone valves vs constant circulationI'm leaning toward a simpler system in terms of components, though I did find the discussion helpful in understanding the concepts. I like the idea of a smart (variable) circ. Have you installed any? Are you able to recommend any particular models?
@ April 2, 2007 7:57 PM in zone valves vs constant circulationIf I understand correctly, Brad White proposes keeping the water flowing in the zone so that the water and the zone cool at the same rate. Then by adding hotter water to the zone's loop using the right controls, you can tune the temperature with high precision. I think this is close to or similar to the system proposed by John Siegenthaler in the Article mentioned by Hot Rod above. I still have a couple questions: This could work if each zone has its own mixing valve and its own circulator. Is there any way to do this with fewer circulators? Also, if the mixing valve is wired directly to the call for heat, does too much hot water get put into the loop before the thermostat is satisfied? If so, is there a good way to control the mixing valve so that it shoots in just enough hot? Thanks, Tim
@ April 2, 2007 7:56 PM in zone valves vs constant circulationThat is great, and I think I am starting to see the light. I'm going to summarize/respond to the original thread below in hopes of eliciting further response without fear of falling.
@ April 2, 2007 7:28 PM in zone valves vs constant circulationThat sounds like a promising idea. Please elaborate. What type of valves? Where do you put them: each zone? Main loop? Thanks, TIm
@ April 2, 2007 7:24 PM in zone valves vs constant circulationI have only one zone in my house (steam heat, no trv's). My programmable thermostat has an up arrow that my family uses when they are cold. The setting reverts to normal either when the temperature is reached or when the next time period arrives, whichever is first. If they raise the temperature and press "Hold Temperature", the setting does NOT revert. A manual TRV or FHV, you'd have to remember to set it back everytime you wanted short term adjustment. It would be like having an automatic "Hold Temperature" for every adjustment. An ideal system needs a way to revert temporary settings automatically or else they become permanent by default. For true effiency you have to accomodate humans or else they will beat the system every time.
@ April 2, 2007 6:53 PM in zone valves vs constant circulationIt seems to me that what I want is to regulate the amount of hot water into the loop based on room temperature, not just circulate the cooling water. What am I missing? When there is a call for heat in the zone, the 3-way or 4-way valves start adding hot water. This brings the room to temperature and then the call ends and the mixing valve prevents fresh hot water from entering. The room begins to cool down while the water circulates and cools down with it. But how is that different than just turning off the zone? Does the circulating water cool off faster because it is cirulating, allowing you to set a tighter delta?
@ April 2, 2007 6:24 PM in zone valves vs constant circulationUnless I am not understanding, it looks to me like the Danfoss FHV's are entirely manual. If a user turns it from setting 3 to setting 5, there is no way to turn it back down other than going into that room and physically turning it back to 3. If this is the case, this limits its usefulness in terms of whole-house control and overall efficiency.
@ April 2, 2007 6:14 PM in zone valves vs constant circulationThat's a great article. Thanks for pointing it out to me. This article suggest three-way mixing valves with a conventional boiler where the loops are short circuited back into themselves when there is no call for heat, as you suggested in your post, with 3-way mixing valves for each zone. It alternativley suggests a condensing boiler with constant circ through a big supply circle. Each emitter loop is independent and has its own circulator which runs all the time. There are "bridges" between the supply circle and each emitter loop in which the flow is controlled by an additional circulator or a zone valve. In this case there is constant circulation in the supply loop and independently constant circ in each of the emitter loops, but heated water passes through the bridges only on a call for heat. Both of these ideas are direct answers to my question. I was actually thinking in terms of regulating flow volume, whereas these are ways of leaving flow constant and adjusting the temperature of the circulating water. So it looks like I need to adjust my thinking. Thanks again.
@ April 2, 2007 4:45 PM in zone valves vs constant circulationI want to be able to control temperature in different floors independently. For me, zoning just means independence. I'm trying to understand which mechanism is best for which conditions. I would also like to keep water temperature low. If the temperature is low, I can keep the floors "hot" as close to all the time as possible, even the low mass ones. So it seemed to me that I would want constant circulation where the water temperature is related to the overall heat load, ie ODR. This seems like it would give me the best efficiency. But how do I control different areas independently? Using traditional zone valves I turn on and off the water to the zone. Is this the only/best way to do it?