Talk:Hydronics

message: No mention of the term "baseboard".  Maybe this term is only used in North America, and whoever wrote the article is from elsewhere?  24.161.96.239 05:40, 16 July 2006 (UTC)
replies: text: This is Wiki, so you know what to do: be bold and edit the article to include it!--Atlant 12:41, 17 July 2006 (UTC)

text: The article is about a particular way of delivering heat from a central location to individual rooms, not about how the heat, once there, is dispersed into the room.  If you wrote about baseboard radiators here, where would you write about electric baseboard heat?  By the way, the British English equivalent of a baseboard radiator is a skirting radiator (baseboards are skirting boards).--GrahamDavies 21:47, 25 October 2007 (UTC)
thread_title:  Baseboard heating 

message: "The Leader in Hydronic Systems and Components", "100% Efficient Radiant Heat Products". It looks and it is advertizing of commercial companies and their products. 194.24.171.196 (talk) 13:03, 28 August 2008 (UTC)
thread_title:  External links contain advertizing claims 

message: How common is it to include steam systems when describing "hydronic" systems? I would qualify the lead sentence by adding "liquid" and expand it a bit:
:Hydronics is the name for the use of liquid water (or aqueous solutions) as the heat-transfer medium in heating and cooling systems.
The chapter on pipe sizing in the ASHRAE Handbook of Fundamentals has separate sections for "Hydronic System Piping" (as a subsection of "Water Piping") and "Steam Piping" (as its own major section). It seems that ASHRAE does not include steam as a "hydronic" system in this context. -Ac44ck (talk) 23:56, 11 December 2008 (UTC)
replies: text: re: steam is/not hydronic, it is in the most literal sense and for the purpose of categorizing heating and cooling systems, but to heating and cooling equipment manufacturers, installers, and service companies the details are different enough to be a specialty. That's why ASHRAE, an industry group, separates the topics. In the unlikely event that Wikipedia develops a sufficiently lengthy description of the differences between a two-pipe supply/return steam heating system and a two pipe supply/return water heating system that it might be helpful to segregate the material into another article and adopting the heating industry's distinction. As long as the material remains vague and generic, the similarities outweigh the differences. For example, oil and gas fired cast iron steam boilers can be used as hot water boilers, although using a cast iron hot water boiler as a steam boiler usually leads to a cracked boiler section because it isn't reinforced internally to withstand the stress of the temperature difference between the water filled part and the steam filled part. At the level of detail a Wikipedia article can explain to the general public, all cast iron boilers are identical. Likewise explaining the differences between a steam radiator and a hot water radiator would focus on technical details not useful to the general public. They both have tubes, surface area, and an air bleeder, and can have a valve to keep it from getting hot. If effort is expended to develop this article, it would be more useful to extend the article to cover the more complex two loop hydronic system used by commercial properties where one loop circulates heated water and one loop circulates chilled water to air handlers and other building systems to provide heat, air conditioning, dehumidification, hot tap water, etc. It would be simpler to ignore 2 pipe seasonal changeover systems and 3 pipe common return systems. PolychromePlatypus (talk) 21:43, 14 November 2020 (UTC)

text: re driveway and walkway snow melting/deicing systems. Aside from areas like lower Manhattan and some campuses where steam distributed in underground utility tunnels warms the walkways anyway, melting systems are made using either direct electrical resistance heating or a water loop scheme similar to radiant slab building heat. Direct electrical resistance heating cables tend to be expensive to operate, electricity isn't a bargain in $/BTU. The cables don't last indefinitely so it has to allow for replacing the cables by putting them in tubes. Putting them in metal tubes to mitigate the shock hazard sets up corrosion problems, but plastic tubes don't age well when heated by a narrow cable and can be damaged by a hot spot when a cable burns out. It was the preferred choice in the late 1960's when electric resistance heating in general was briefly popular. Nuclear power was going to make electricity so cheap it wasn't worth metering it. Things didn't turn out that way. The water loop requires using a non-toxic antifreeze like propylene glycol or limonene (citrus based) to avoid burst tubes. Separating the low temperature antifreeze loop from the heat source with a heat exchanger, similar to an indirect domestic hot water, confers two benefits. First, it avoids the putting the reduced heat capacity of an antifreeze mixture in the boiler which would decrease the boiler's heat exchanger capacity and efficiency. Second, the water returning to the boiler from the indirect heater isn't intrinsically ice cold like the water returning from under the frozen driveway. Without a water to water heat exchanger there would still be a second pumped loop but it would have a mixing valves so that 32°F water didn't return to the boiler. Excessively cold return water can cause condensation in the boiler which absorbs flue gasses becoming acidic and eroding the boiler. Excessively cold return water also creates a large thermal gradient across the boiler with the thermal expansion difference creating large stress forces, which can result in cracking. A gas or oil fired boiler is being assumed because a heat pump isn't efficient in precisely the kind of outdoor conditions when a driveway heating system would be operated. If a large geothermal heat sink is available at a particular site that assumption might be incorrect and the heat source for the antifreeze loop might be a heat pump. PolychromePlatypus (talk) 21:43, 14 November 2020 (UTC)
thread_title:  Steam 

message: Steam is a completely separate method of distributing/transferring heat throughout a system, it should not be mentioned under the "Hydronics" section EXCEPT as a potential source of heat through the use of a steam-to-water heat exchanger that transfers the heat from steam to the Hydronic "Closed Loop" water system. This approach is used when the facility or building has other steam loads and wishes to confine their boiler type(s) to steam only. If no other steam load exists then hot water boilers are usually installed.
Steam is a more efficient form of providing heat to a building due to it's higher heat transfer coefficient. From a design/build standpoint a Hydronic system is less expensive to purchase & install, so many owners will take the lower up-front cost of a hydronic heating system & pay more operating/fuel costs throughout the life of the system.
Hydronic baseboard heaters are classified as radiators, the core or tube bundle is fabricated of finned tubing that air either passes over via natural convection or is blown over by a thermostatically-controlled fan. 
There are no 1-pipe or 2-pipe systems associated with Hydronic systems. There are primary & secondary loops & zones. The primary loop runs from the boiler room (this end of the loop is called the "supply" piping), throughout the building and returns to the boiler room (this end of the loop is called the "return" piping). It's job is to circulate hot water throughout the building, and includes circulating pumps for this purpose. The secondary loop refers to the design of the boiler piping integration into the primary loop for keeping the primary loop at it's temperature setpoint. The zones pull water from the primary loop supply & pass it through the actual "Load" (air handler coil, re-heat coil, baseboard heaters, etcetera). The cooler water which has given up a portion of it's heat to these "loads" then feeds into the return piping of the primary loop. From there it returns to the boiler room to be reheated & recirculated. 
Sdunaway (talk) 23:00, 8 October 2009 (UTC)
thread_title:  Clarifications on Hydronics