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Adding heat to a new extension

Recently I added a 600 sq. ft. extension to my 40 year old 1200 sq.ft. ranch. I have to tell you that I've met every shoddy contractor that Long Island has to offer. I myself have a fair amount of mechanical aptitude but have always thought its better to call a trade professional then try to learn a new one. Well I've been proven wrong way to many times so at 60 I'm here to sharpen my skill set.
My immediate need is to at least become educated in how to best add a new zone to my old 2 zone heating system.
Currently the new construction I added to the rear east wall of my home is 20 X 30 with a full basement. Insulating it with R38 and R15, ceiling and walls. There are 8 - 3X5 Anderson 400 series windows and 1-6' slider (Anderson 400). Ceiling height is 9' average with 3 exterior walls. Using the web I've done some generic heat loss calculations and came up with 28K btu. Again using the web I would need 48+ linear feet of fin tube baseboard. My boiler supply home run would be approx. 50' (6' head). The return would probably be at least 80' from the last baseboard.
My existing gas boiler is original Thermotron 1973, I know I will be upgrading that in the near future but it still works well, I open it up every year to inspect, vacuum and wire brush. I have two small Taco circulators, one for the existing finished basement, the other for the upstairs living area.
My thought is to add a third circulator (possibly a Taco 009IFC) and plumb with 3/4 Pex.
I'm I on the right track here, what do you gentlemen think?

Re: Adding heat to a new extension

I admire your will to do things yourself, but HVAC is not exactly a trade for a person like you. Hire a pro. To save money, ask them if you could install the vents, registers, insulation and other things.

When calling subcontractors for a specific job, you need to weed out the flakes by doing your homework: check references, verify information, check with the state contractor board, etc.

I'm all for folks doing it themselves, but making mistakes means losing time and money. Can you afford that?

Re: Adding heat to a new extension


Perhaps dj has a point; there's only a limited amount of advice we can give you sight unseen of the setup you have in this particular building; just from reading your post it sounds like your numbers seem to be right on, but you haven't told us anything of your specific location in LI; are you near the water, do you get any zero degree or lower winter weather or have any other location problems that might compound the usually straightforward job of what amounts to mostly putting another zone on your boiler system---in such cases it might be better, for example to use high output baseboard or even baseray cast iron baseboard on at least one of the inside exterior walls to make sure you get enough heat in there (with all that glass & high ceilings) to make the room comfortable; figure 35 or 40 btu/square ft. and 430 btu/linear ft @ 160 degrees water temp (at 1 gpm hw flow) for std baseboard & 620 btu/linear ft. @ 160 deg water temp (1 gpm) for hi-output BB; cast iron Baseray has approx 520 btu/linear ft. @ 170 degree water temp; it's a lot more expensive than aluminum fin/copper BB, but it retains the heat lots longer than aluminum fin/copper & may be the way to go on this project; always install the baseboard/convectors at least 1 or 2" above the floors mounted on the THREE EXTERIOR WALLS to counteract the cold surfaces & improve the chimney effect of warm air circulation throughout the room.

I dont see any need to use a high end Taco ZV, where a standard 3/4" Taco 571 series ZV with a separate T-stat zone should do the job at a much lower cost; I would also use a floor vector (Beacon-Morris site below) in front of the Slider (easily connected to the sub-floor 3/4" continuous HW loop) to offset the cold air you'll be getting there; at the Beacon Morris site, click onto "view residential products" & "view additional residential products" to see a photo of a floor vector.

At this point I think it would be a good idea to get at least one or two on-site quotes from local HVAC contractors, who would walk thru the proposed job with you at their side pointing out what they feel needs to be done on this project & the components that should be used in regards to whether you can use your present boiler, insulating or otherwise modifying the 50 ft. & 80 ft. runs for the new zone's supply & return piping & whether the output of your present boiler is sufficient to handle the additional 28k heating load----I think you'd gain a much better grasp of how this project should be done after getting feedback from 1 or 2 contractors---keep an open mind; nearly all contractors will take the effort to come out & give you what they feel is an honest evaluation of what the job needs; consult the Yellow Pages under "Heating Contractors" & search the display ads for those specializing in hydronic heating systems; also consult "Heating Equipment Parts & Supplies" & call & speak to the COUNTERMAN of several heating parts outlets in your area to get a referral of an experienced HW heat contractor---you have everything to gain & nothing to lose by having 1 or 2 heating contractors come in & look at the proposed job & give you their estimates & cost quotes----at that point, you'll be in a better position to decide if you want to hire someone or do the job yourself.

After reading your post several times, I still have concerns as to if you need a new boiler now (is this make of boiler situated outside the building & what is its total input, or IBR output in BTU/hr)??? does it have an indirect HWH or a tankless heater coil for your present domestic HW needs (showers, sinks, etc.) ???


Re: Adding heat to a new extension

DJ1and Pelton, thank you both so much for responding. Let me qualify my mechanical aptitude by saying I'm a master electrician that specialized in industrial automation. I have extensive training and experience in
hydraulics and pneumatics.
I do understand your concern and would like nothing more then to call in a "professional" but having seen a lot of the trades in my area it would take a fair amount of searching before I would feel comfortable with one let alone two. However I will take your advice and make a few phone calls.
OK, that being said I still wish to become an educated consumer, my neighbor recently upgraded to a high efficiency boiler, loves the bills but hates the heat. I know what I'm sure to hear. my old boiler is out of date and needs replacing. At present it meets my needs and can't be added to the budget for at least 2 more years.
The hot water is separate from the boiler, the boiler is a Thermotron 125K BTU/Hr.In. and located in the basement it has been well maintained.
Most of the electrical controls have been replaced and upgraded over the years. I bought the house in '88 originally it had two line voltage T-stats, both zones are now 24v.
The house sits about a mile inland from water, the slider is on a southern exposure with 2-3X5 windows, eastern exposure has 4-3X5 and northern side 2-3X5. Average Dec/Jan/Feb temp are in the 34-36ยบ range.
I had also looked at Runtal baseboard but couldn't justify the price.
I will however now consider a higher output using lower water temperature based on your comments.
Please humor me, over the years I've learned to always ask questions and realize when I'm in over my head. I do feel with the right information I could do this project, but, no without sound advice.

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