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Is my system way too small?

Dave_121Dave_121 Member Posts: 4
It is hot air.


  • Dave_121Dave_121 Member Posts: 4
    Is my system way too small?

    I bought a new interior townhome in Oct 06. It is about 2200 sq ft with three floors of living space. The house is located in the Philadelphia suburbs. When we first moved in the builders installed a 50,000 btu heating unit. The system would run just about constantly and we would not feel too much difference in the temp. This on days when it was about 35 to 45 degrees. Upon my complainging the builder put a 75,000 btu unit in. We did notice a slight imporvement but it was still not what up to our expectations. I know calculations and windows and doors go into knowing exactlly what size system is needed, but are totally off on the size? What size should probably do the job? Thanks
  • Mad Dog!!!!!!!!Mad Dog!!!!!!!! Member Posts: 157
    If house is well-insulated ....

    it IS probably fine (boiler size). The home could be under-radiated though. Do you have enough baseboard or convectors, radiators? There is a very good heatloss program avail. here. One way to find the math. Mad Dog
  • jim lockardjim lockard Member Posts: 1,059
    Kind of heat

    Hot air? Hot water?
  • joel_19joel_19 Member Posts: 931

    Does that mean you have a center unit with only 2 walls exsposed? is the place insulated? I'd be looking for a problem but the boiler or furnace wouldn't be it. Have a Comfort Institute contractor perform a blower door test and if you have hot air have them perform a duct leakage test.

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  • kal_2kal_2 Member Posts: 60
    frst question, terminal type...

    huh? "terminal type" is thechni-speak for the type of heat emitter you have in your house - is it the, long fin tube baseboard, cast iron radiators, or a hot water coil in the central air, or radiant in concrete or radiant in wood, - it makes a real difference, as heat loss calculations, don’t take into account the comforting effect of infrared radiation – ie: if you have fin-coil baseboards or water coil in the ac, then you are way under sized, because heating air to heat people, is not only wasteful, but also uncomfortable, whereas, if you are bathing people in infrared light from a radiant floor or exposed cast iron radiators, you should have enough btu’s there to do the job – had a basement with 14ft of fin-coil baseboard, and the lady was always cold, and her zone was on 24/7, – I chucked out the baseboard, and put three 6 section sun-rad cast iron radiators – and she is not only warm, but her zone only goes 15min our of the hour – the gas company had to re-adjust the whole yearly budget – that’s how much gas they saved - mad-dog heats a huge exposed house with steam radiatiors for less than i heat my 1700sqft apartment with forced air

    the dead men who lived through the Spanish influenza of 1918 that killed millions of people across the planet – knew one thing – they had to heat houses with the windows open – so there goes the heat loss calculation right out the window literally – so what did they do?, they installed tall cast iron radiators “visible” all over each room – and presto instant comfort – go to Aspen or the Swiss Alps – as long as you are in the sun you are boiling – the second you cross into the shade you are freezing – try this, go to someone’s home with cast iron radiators – wait until the radiators have cooled to 80f with a thermometer – so that it actually feels cool to the touch – now hold your palm a short distance off the surface – and you hand will feel warm – RAY-DEE-ANT is a beautiful thing – cast iron radiators is the least expensive way to get you there – and if you need to re-pipe it – remember – you can snake 1/2” pex tubing from a brass radiant manifold to each radiator as easy as snaking bx electric cable – do it all the time
  • hot rod_6hot rod_6 Member Posts: 179
    stab in the dark engineering

    often fails :)

    A heat loss and gain calc would be the best first step.

    Next determine if you have enough distribution either vents and duct work, or pipes and emitters.

    It could also be in the mechanical room as mis-piped hydronics or un balanced forced air.

    Best bet would be a contractor that would calculate and present options after a site visit.

    Typically 50,000 would cover a well built and insulated home. But it all depends :)

    hot rod
  • Dave_121Dave_121 Member Posts: 4
    Air flow

    The air coming out of the vents is extremely low to almost nothing. But I am told by the builder that it is more than enough to do the job. Just wanted to throw out another symtom.
  • kal_2kal_2 Member Posts: 60
    so it's \"scorched\" air...

    one unit for three floors, forget it, not ever going to be right, you need to invest in a hot water radiation solution, if you think you cant afford it, double the price of gas and recalculate - you WILL pay for it, whether you get or just keep paying for it again and again is entirely up to you - that what i tell my customers - every one pays for modulating and condensing boilers with radiant heat – whether they have or not is up to them, but the monetary expenditure is built in to the waste of the old system – every 7 to 10 years you will pay for a brand new system again and again and again… – that interval number gets shorter as the price of gas goes up – I am not saying that you need to redo all your floors and do floor heat – nice and visible cast iron or panel radiators will do almost as well on the economy scale, ps if you are redoing any bath – please,please,please put electric radiant in, it’s not expensive to do or to run during bathing times
  • jim lockardjim lockard Member Posts: 1,059
    The greatest furnace

    in the world can not work on a poor duct system Dave, and that sounds like what you have a poorly designed leaky duct system. Is your main duct metal or fiberglass--seen alot of fiberglass ductboard in Pa.
    Couple of things you can try bring in a contractor to perform a energy audit of your HVAC system, armed with that knowledge go back to your builder and demand he correct the problem.#2 Replace the existing furnace with a variable speed model that will adjust to the static pressure of the duct system.#3 Install a damper system in the existing duct work that will adjust with the tempature.#4
    Add a ductless split system on the top floor of your home for the coldest and hotest time of the year. Best Wishes J.Lockard
  • Plumdog_2Plumdog_2 Member Posts: 873

    Have someone do a search for duct blockage; particularly in the Return Air side of the duct. Little to no supply air can be an indicator of restricted or blocked intake air.
  • joel_19joel_19 Member Posts: 931

    The problem is most likely in the ductwork go fird a Comfort Institute certified contractor and they will be able to solve your problem.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • jim lockardjim lockard Member Posts: 1,059
    Y not

    Just take off the blower compartment door? Then go around and see if things change. J.Lockard
  • lee_7lee_7 Member Posts: 458

    where in the philly burbs are you located?
  • Dave_121Dave_121 Member Posts: 4

    Pottstown off of 422.
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