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efficiency of hydronic vs forced air?

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weil_fail
weil_fail Member Posts: 84
edited March 2022 in THE MAIN WALL
whenever I try to google topics like this, it seems like I'm always hit with a lot of marketing material from both sides. I've heard that hydronic is efficient because you feel warmer if the floor is heated more vs if the air is heated, and also that ducts lose some heat into the walls. has anyone ever replaced one with the other and actually seen how it works out in practice?
«13456

Comments

  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,578
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    I’m sure that there is at least one old post here about someone’s disappointment with higher heating costs, after having replaced a hydronic system with forced air-perhaps so as to have A/C.
    Maybe someone will be able to find it.
    There are probably numerous posts of situations where an an old, badly maintained steam system has been replaced, and its costs unfairly compared to the new,
    Think of a 10 year old car, with dragging brakes, under inflated tires,and dirty spark plugs, compared to a new one. —NBC
  • psb75
    psb75 Member Posts: 847
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    In a room with forced-air heating, think of "wind chill": air moving past a person's skin makes them feel several degrees colder than the actual prevailing temperature. Now...what if things in the room (most especially the entire floor) were all nice and warm, and there was very little convective air movement--almost like the warming rays of the sun on a calm day. This condition is the opposite of "wind chill." This is a bit of an exaggeration put the basic principles hold. Radiant, hydronic/steam heat is better than heat provided by moving hot air. If done right, it is much more comfortable, quieter and more efficient.
    SuperTechdwatson3Voyager
  • Hot_water_fan
    Hot_water_fan Member Posts: 1,898
    edited March 2022
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    Your mileage will definitely vary here. A well done hydronic system and well done forced air system will both be efficient. The most concrete hydronic advantage is distribution efficiency. The hydronic system will use less energy to move the heat if pumped efficiently (or if steam). Outside of that, I don’t think in-floor heating is more efficient in practice, that leans more marketing to me. For that to be true, a radiant floor/ceiling/whatever needs to be accompanied with a lower thermostat setting. Duct losses may be significant or not at all, that depends on if they’re inside the building envelope and insulated/sealed correctly as well as the temperature of air within them. Generally, I’d expect total energy of a hydronic and forced air system to be very close on the residential side if installed well. 
    RichinTenn
  • hot_rod
    hot_rod Member Posts: 22,342
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    So many efficiencies at play. The building itself dictates the load regardless of the heating system,
    Next is the conversion of the fuel to actual useable heat. The less that goes up the flue the better😉
    Then the distribution efficiency, a forced air blower and duct work, or a small circulator.

    FA equipment has gotten more efficient with condensing technology, ECM blowers and microprocessor controls, so a wash in that respect 

    properly sized and installed hydronics and radiant are more comfortable, to me.
    With forced air you can have cooling and better IAQ control, filtration etc.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • clammy
    clammy Member Posts: 3,113
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    Those are all great points ,especially w indoor air quality ,ecm blowers and better electronics and of course more energy efficient building envelopes and lower fuel usage due to it . I guess I will be always a new old timer when it comes to a lot of things which isn’t a bad thing in some ways and I ll always be a hot water steam guy . What a lot of people discount is that it has a lot more to do w the quality of the rest of any install which dictates how things perform.. There’s a lot that goes into any system install weather hot air or hot water and most of the devils work is in the details which always involve more time from hanging,sealing and insulating ducts w real insulation ,not bubble gum wrap to adding isolation insulators to piping going threw beams and floors and running pipes and figuring to add insulation when completed to hanging and supporting your piping properly even though it’s a pex eats pex world out there . It s all good I really wonder in 50 years what will be the deal ? Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Steamhead
    Steamhead Member Posts: 16,940
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    weil_fail said:

    .... has anyone ever replaced one with the other and actually seen how it works out in practice?

    @gerry gill replaced forced-air with mini-tube steam some years ago, and ISTR the fuel savings were significant.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • psb75
    psb75 Member Posts: 847
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    I really like converting houses from old forced air systems to hydronic heat--pulling out all the old duct work and showing the owners all of the recovered space and having them see all of the dirt and pet hair inside the ducts. I then use the duct pathways to run the pex lines for the panel radiators. They can't quite believe the lack of noise when the system is operating. Of course they also enjoy the superior comfort and control of the heat delivery--cooler bedrooms, warmer common areas and bathrooms.
  • GroundUp
    GroundUp Member Posts: 1,938
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    A BTU is a BTU. If every square inch of the space is the exact same temperature, the exact same amount of BTUs are required- regardless of heat source.
    mattmia2motormanEricPeterson
  • wmgeorge
    wmgeorge Member Posts: 222
    edited March 2022
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    You can not beat a Hydronic or Steam for comfort.... Heating. You folks in the NE do not seem to use A/C so that's the way it is.

    You love flex duct as its easy and cheap and does not require skill.

    Out here in the flat land we need A/C and use for the most part High Effy gas furnaces or HPs. We run real ductwork and have decent air flow with our 96% equipment. Our houses are larger and designed for ducts.

    I have none of the cold air chills when heating because of proper placement of supply registers and myself I run my ECM motor for air flow on low 24/7/365. Balanced the air flow ducts and I am A OK. My fan motor has been switched that way since 2007.

    My Trane is 96% your confusing, efficiently with comfort with those 75% old boilers.

    Oh and I run MERV 11 or better filters and have my ducts cleaned. The dirt is still in the house wither its in the duct or setting on the floors, its a matter of cleaning!
    Old retired Commercial HVAC/R guy in Iowa. Master electrician.
    Hot_water_fan
  • ChrisJ
    ChrisJ Member Posts: 15,857
    edited March 2022
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    I installed ductwork and a split system for A/C but I would never change my cast iron radiators.
    I also prefer steam to heat the cast iron, but I wouldn't be against hot water or some other means.

    That said, I feel a properly engineered and properly installed forced air system works fine but most are far from it. It also seems like the constant "hot/cold/hot/cold" from them is greatly reduced with multiple stages but is never completely gone.

    I used flex in my duct system intentionally for sound attenuation and after the first season even cut out 10' of hard pipe and replaced it with flex. Flex duct is just as much "real ductwork" as galvanized steel, especially if you're running 28 and 30 gauge. But like everything else flex must be installed properly. No long runs, no tight turns and the flex must be pulled tight, no sags. I.E. I used galv steel elbows for my 90s and the only bends on the flex are very subtle. Anything over a 10' run is hard piped, flex becomes too restrictive IMO and some even limit this to 5'.


    I run a MERV 8 Air Bear 20x25x5 filter on a 1200cfm system and wouldn't recommend any higher MERV for a residential system due to static pressure concerns.


    Ultimately, I feel in the end there's much more to a system than it's efficiency and the efficiency between a modern hot water system and forced air system are close enough it's irrelevant and shouldn't be a deciding factor between the two.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    SuperTechCanucker
  • psb75
    psb75 Member Posts: 847
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    You can't beat forced air for cooling--I'll give you that. Like I said, air moving over peoples skin makes them feel cooler. And speaking of keeping duct work clean--you mention the benefits of flex duct--how is that stuff cleaned?
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,551
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    I wrote this one awhile back. I'm standing by it:

    https://heatinghelp.com/blog/how-do-you-define-high-efficiency/
    Retired and loving it.
    SuperTechMikeL_2
  • ChrisJ
    ChrisJ Member Posts: 15,857
    edited March 2022
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    psb75 said:

    You can't beat forced air for cooling--I'll give you that. Like I said, air moving over peoples skin makes them feel cooler. And speaking of keeping duct work clean--you mention the benefits of flex duct--how is that stuff cleaned?


    I'm not really a believer in duct cleaning.
    The filter stops anything from the returns from passing through the system and if the filter is working reasonably well the supplies should remain reasonably clean.

    That said, I have seen companies clean flex. They seem to do really good at it too.

    I should probably word that differently. I'm sure there's some really gross ductwork out there....... (Thinking about the phone full of roaches)........ugh.

    Anyway,

    As far as forced air for cooling, radiant cooling is far superior as far as comfort. You still need some kind of dehumidification in addition to it though. Even so, I'm sure a well engineered properly working forced air cooling system would be preferred over a broken and or poorly designed radiant cooling system.

    Forced air cooling is certainly preferred over radiant when it comes to cost and simplicity.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Alan (California Radiant) Forbes
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    There are some things I don't promise my customers. Fuel savings is one. My experience is that while radiant puts the heat where its needed, you have to leave it on for longer. With that, it's pretty rare for a customer to reject radiant just because he or she wants to save money. Most are attracted to radiant because of what they hear about the comfort of it.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    ChrisJ
  • hot_rod
    hot_rod Member Posts: 22,342
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    One telling measurement is the flue gas leaving the buildings. The lowest possible flue gas would indicate the most efficient appliance

    With some hydronic systems you can heat with water below 120F, flue gas a bit higher
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mattmia2
    mattmia2 Member Posts: 9,838
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    Unless you are extremely careful about sealing supplies and returns and balancing the supply to the return of each room, forced air is going to create some pressure differential that increases infiltration. Certainly less in a really tight building, but in the normal case of a mediocre installation and mediocre construction there will be more infiltration with forced air.
    jpm659er
  • ChrisJ
    ChrisJ Member Posts: 15,857
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    mattmia2 said:

    Unless you are extremely careful about sealing supplies and returns and balancing the supply to the return of each room, forced air is going to create some pressure differential that increases infiltration. Certainly less in a really tight building, but in the normal case of a mediocre installation and mediocre construction there will be more infiltration with forced air.

    To be fair,
    If it's a mediocre build, mediocre hydronic installs aren't exactly good. They usually have some really serious problems that never seem to go away.

    Some feel infiltration is a good thing. To an extent.
    It also depends on what your family ate recently.

    On that subject, forced air spreads smells rapidly while radiant style systems like in floor, in wall, baseboard and cast iron radiators tend to not spread them much, if at all when doors are closed. Whether this is food smell, or, other smells........

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    delcrossvSuperTech
  • ChrisJ
    ChrisJ Member Posts: 15,857
    edited March 2022
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    Wait.
    Why am I defending forced air at all, all of a sudden?!?

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    mattmia2SuperTechCanucker
  • Jamie Hall
    Jamie Hall Member Posts: 23,536
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    ChrisJ said:

    Wait.
    Why am I defending forced air at all, all of a sudden?!?

    Life is strange, @ChrisJ ! Bottom line on all of the above is this: any heating system will work, and work well, if it is properly designed, installed, and maintained. Any system will work poorly if it isn't. Energy efficiency doesn't enter into the choice of type, but customer comfort and preference does.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    MikeAmannCanucker
  • GroundUp
    GroundUp Member Posts: 1,938
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    @mattmia2 please inform us why it is that you disagree with the fact that a BTU is a BTU. Do a heat loss calc on any given building with any given program- does it ask what the method of heat delivery is, or does it just give a number?
    wmgeorge
  • mattmia2
    mattmia2 Member Posts: 9,838
    edited March 2022
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    @GroundUp I disagree because different delivery methods change the heat loss of the structure. In an ideal world forced air wouldn't change the heat loss of the structure but in virtually all installations it both uses panned cavities for air returns that ultimately have leaks in to unconditioned spaces and causes pressure differentials between rooms that increase infiltration and exfiltration.

    Heat loss calculations may not be able to account for it and it may be less than the effects of wind on the worst day but on a calm day it is making things worse.
  • MikeL_2
    MikeL_2 Member Posts: 500
    edited March 2022
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       It can be difficult to realize the advertised efficiency of the modern atmospheric or mod / con boilers, especially in existing homes where the baseboard heat, radiators, convectors, or ahus were sized to work with 180° supply water temps.
       A boilers ability to heat indirect domestic water heaters that have low standby heat loss should be a factor in comparing overall efficiency to warm air furnaces.
         In my view a hydronic systems versatility makes it a better choice for comfort in Northern climates. A warm air furnace cannot effectively or efficiently provide energy for radiant floors & walls, snow melt, towel bars, or swim pools & spas.
    SuperTech
  • Paul Formisano
    Paul Formisano Member Posts: 24
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    Efficiency is about the same for well designed systems.  That being said, I went with radiant in floor for my house when I built it because it is more comfortable and silent.  However, I had to add some ducts for air conditioning, but you could go with a mini-split to avoid that.  I didn’t want to see or hear an air conditioner so I didn’t use a mini-split.

    Forced air is easy to add air conditioning to.  It’s also easier to humidity in the winter.
  • veteransteamhvac
    veteransteamhvac Member Posts: 73
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    Having two systems (hydronic for heat and forced air for cooling) seems like overkill, but in my experience the air handlers and condensers that only operate AC seem to last much longer than combined furnace/AC systems. I don't have any hard data to support this, just personal experience.
    wmgeorge
  • wmgeorge
    wmgeorge Member Posts: 222
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    mattmia2 said:

    @GroundUp I disagree because different delivery methods change the heat loss of the structure. In an ideal world forced air wouldn't change the heat loss of the structure but in virtually all installations it both uses panned cavities for air returns that ultimately have leaks in to unconditioned spaces and causes pressure differentials between rooms that increase infiltration and exfiltration.

    Heat loss calculations may not be able to account for it and it may be less than the effects of wind on the worst day but on a calm day it is making things worse.

    Infiltration comes from air leaks into the building from loose fitting windows and doors plus sloppy construction. Not from forced air systems unless they have an outdoor makeup air or ventilation system. Out here where we have building Codes, the houses are so tight they are required to put in air to air heat exchangers. Furnaces and DWH take combustion air from outside the structure.

    Manual J calculations and Manual N for that matter have infiltration and ventilation rates to be entered into the load calc.
    Old retired Commercial HVAC/R guy in Iowa. Master electrician.
    GroundUp
  • ChrisJ
    ChrisJ Member Posts: 15,857
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    Matt's correct, forced air systems tend to aggravate infiltration in older buildings.
    Even with perfectly balanced supplies and returns there will likely be some pressure difference, even so small you can't measure it.

    Most systems seem have really bad balance especially in older buildings and added in systems (let's rip out steam and put forced air in!) and that air needs to return one way or another and it often takes a short cut via bad windows etc. This causes dry indoor air which people then add humidifiers to compensate for.

    The house I grew up in which was built in 1958 had no returns in any bedrooms and the windows were ok but not great. This meant that air was being forced under and around doors when closed, and likely out the windows of those rooms and then cold air was pulled in through windows by a return. The air in that house was always extremely dry all winter. A radiant system in such a setup would do a lot better.

    I'm pretty sure we've seen situations on here where people had super tight houses and actually needed to get rid of humidity in the winter from cooking, breathing etc.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    SuperTech
  • Jamie Hall
    Jamie Hall Member Posts: 23,536
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    One of the more interesting things about working with old buildings (old by my standards being pre-1900 at least), and country ones at that, is -- at the risk of sounding like a flower child or something -- most of them were designed to work with the natural environment around them, not impose themselves upon it. The groundwater is high around one side of your basement in the spring? OK, put in a drain out the other side and put things on shelves (I worked on one house where, in the spring, one entire wall of the basement was a real honest waterfall -- lovely to look at). If it's high all around, don't put in a basement. Site the house behind a windbreak -- or plant one. Minimize draughts, yes, but accept them -- if you're heating with a fireplace or even a big stove, you're going to have them anyway. Gets too hot in the summer? Plant shade trees and have lots of doors and windows (one place I work with has something like 19 outside doors...). Uncle Silas's bedroom is cold in the winter? Give him an extra quilt (though it probably wasn't -- I've worked with seventeenth century houses which were more evenly heated than many modern ones). And so on.

    The general realisation was don't fight Mother Nature. You're going to lose, and be miserable while you are losing.

    Not to say that control isn't possible. It is, up to a point, and for many modern people it is desired. Just to say that it is going to take real thought and effort to do it.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Hot_water_fan
  • GroundUp
    GroundUp Member Posts: 1,938
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    mattmia2 said:

    @GroundUp I disagree because different delivery methods change the heat loss of the structure. In an ideal world forced air wouldn't change the heat loss of the structure but in virtually all installations it both uses panned cavities for air returns that ultimately have leaks in to unconditioned spaces and causes pressure differentials between rooms that increase infiltration and exfiltration.

    Heat loss calculations may not be able to account for it and it may be less than the effects of wind on the worst day but on a calm day it is making things worse.

    Perhaps you did not read what I typed. "IF" every square inch of area is the exact same temperature, the heat loss is the exact same. Forced air vs radiant, the temps are only the same at thermostat height- if even that.

    I have played with this in my outbuildings. Both about 1600 sq ft, both with radiant floors, and both with forced air coming from floor level. One has 10ft sidewalls and the other has 14ft sidewalls. The shorter one will use approximately 10% less fuel to keep at a given ambient temp with the radiant versus the forced air. The taller one, close to 20%. The reason for this is because in order to maintain 60 degrees at 5ft high, the average temp in the space is considerably higher using forced air because the hot air rises to the ceiling and stays there to leak out through the lid, ceiling fans or not. Do you often see ducted returns at the ceiling instead of the floor? Me neither. Of course the argument can also be made that the same comfort level is achieved with a 3-5 degree lower thermostat setpoint using the radiant, so again fuel usage is further reduced.
    Solid_Fuel_Man
  • wmgeorge
    wmgeorge Member Posts: 222
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    Most duct designers put dual Returns on a high dollar job. High returns for A/C, low for Heat same duct for both but dampers in the Registers for when you switch seasons. Pretty basic stuff.
    Old retired Commercial HVAC/R guy in Iowa. Master electrician.
    ChrisJ
  • ChrisJ
    ChrisJ Member Posts: 15,857
    edited March 2022
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    wmgeorge said:

    Most duct designers put dual Returns on a high dollar job. High returns for A/C, low for Heat same duct for both but dampers in the Registers for when you switch seasons. Pretty basic stuff.

    I've never seen a return grill with a damper?

    Can you give an example? I used filter grills and then abandoned the filters but I don't recall ever seeing normal return grills with anything either.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    SuperTech
  • wmgeorge
    wmgeorge Member Posts: 222
    edited March 2022
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    ChrisJ said:

    wmgeorge said:

    Most duct designers put dual Returns on a high dollar job. High returns for A/C, low for Heat same duct for both but dampers in the Registers for when you switch seasons. Pretty basic stuff.

    I've never seen a return grill with a damper?

    Can you give an example? I used filter grills and then abandoned the filters but I don't recall ever seeing normal return grills with anything either.



    Do a google you folks out there have never seen but they exist and are used. FYI any sidewall register can be a Return and with a damper.
    Old retired Commercial HVAC/R guy in Iowa. Master electrician.
  • delcrossv
    delcrossv Member Posts: 748
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    All I can relate is personal experience.

    Having two systems (hydronic for heat and forced air for cooling) seems like overkill, but in my experience the air handlers and condensers that only operate AC seem to last much longer than combined furnace/AC systems. I don't have any hard data to support this, just personal experience.

    My folks house (built in the 1950's) was done that way. Still on its original boiler and we finally replaced the air handler and condenser two years ago. (IIRC the system was on its 3rd compressor when we finally swapped out the whole thing).

    Best working system I've experienced- each set up for what it does best. High supplies and low returns for AC, fin tube/radiant for heat. No compromises.
    Trying to squeeze the best out of a Weil-McLain JB-5 running a 1912 1 pipe system.
    Solid_Fuel_Man
  • Jamie Hall
    Jamie Hall Member Posts: 23,536
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    Oh the wonders of forced air. Huge ducts all over the place... there's a reason that stores and office buildings usually have 12 to 14 foot floor to floor heights and suspended ceilings. And, if multi-story, ample duct shafting. Or high velocity VAV systems... getting truly adequate and correct ducting into normal residential construction can be an interesting challenge, to put it mildly. Never mind retrofits...

    The dampers for the returns (or supply) ducts don't have to be at the registers. They can be anywhere along the duct length. That said, in a higher dollar installation, they should be controlled by the system, so that the correct ducts are open at the correct times. No big deal -- just more motorized dampers and a few relays -- but it should be done. You can't count on the homeowner to go around opening and closing register dampers in response to whether the HVAC system is running in heating or cooling mode... they won't.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    CanuckerSuperTech
  • wmgeorge
    wmgeorge Member Posts: 222
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    Perhaps the home owners out here are a little smarter. You can't count on the homeowner to go around opening and closing register dampers in response to whether the HVAC system is running in heating or cooling mode... they won't.

    And its low returns for heating and high or ceiling returns for cooling warm air rises. If it was not for forced air H&C large buildings would not exist. I have worked on many hot deck cold deck multi zone AHU units with the old pneumatic zone control thermostats. Now its VAV or other system, some with reheat in the VAV boxes.
    Old retired Commercial HVAC/R guy in Iowa. Master electrician.
  • ChrisJ
    ChrisJ Member Posts: 15,857
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    Would displacement cooling be considered forced air?

    I guess, technically. ?

    I believe some airports etc use displacement cooling and radiant heating.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JK_Brown
    JK_Brown Member Posts: 24
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    I just watched youtube video by Matthias Wandel (Matthias Random Stuff) 'Where does the heat go when you heat a room?'. Using a space heater, the tracks the temperature as it heats a shed (and then a bedroom), fitting curves and such. He arrives at what's known here, that the walls and furniture are where all the heat is stored. So do you heat the air to heat the walls and stuff or do you heat the floor and walls to heat the air? If the former, Matthias pointed out the old wood paneling of the 1970s is better than exposed drywall due to the low heat content, i.e., less heat lost heating the walls.

    Of course, a system that heated the walls, floor, and/or ceiling for cold winter base load, then used force air for the transient demand/warm up, is probably the best of both worlds.

  • ChrisJ
    ChrisJ Member Posts: 15,857
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    JK_Brown said:

    I just watched youtube video by Matthias Wandel (Matthias Random Stuff) 'Where does the heat go when you heat a room?'. Using a space heater, the tracks the temperature as it heats a shed (and then a bedroom), fitting curves and such. He arrives at what's known here, that the walls and furniture are where all the heat is stored. So do you heat the air to heat the walls and stuff or do you heat the floor and walls to heat the air? If the former, Matthias pointed out the old wood paneling of the 1970s is better than exposed drywall due to the low heat content, i.e., less heat lost heating the walls.

    Of course, a system that heated the walls, floor, and/or ceiling for cold winter base load, then used force air for the transient demand/warm up, is probably the best of both worlds.

    When you heat an object in a room, there's no heat lost it's simply stored, like a flywheel. Which you actually mentioned.

    So I'm a bit lost at the drywall vs wood paneling example.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    wmgeorge
  • JK_Brown
    JK_Brown Member Posts: 24
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    ChrisJ said:

    So I'm a bit lost at the drywall vs wood paneling example.

    The wood paneling is light and airy so would slow the take up of heat from the air, whereas the drywall would draw heat out of the air. The paneling would also reduce the heat sink feeling.

    Of course, time and context is important. Heating a cold, unheated space with a space heater/forced air would feel warm faster with paneling, but long term heat will migrate into the drywall, just slower. The great tapestries on the walls of castles were mostly to block the cold stone from feeling like a giant looming ice cube.

This discussion has been closed.