heating dilemma - oil, gas, radiant, forced air, old house...

mass_biker

Hi all - we are in the process of renovating a 100+ year old victorian in the midAtlantic; the house is currently heated by an oil-fired system driving hot water through cast iron radiators throughout the house (3 stories) - all on one zone/one thermostat. The house does have gas from the street; currently used for hot water and washer/dryer.



We are beginning with renovating the kitchen. In the process, we are going to put in AC for the kitchen/master suite (didn't have it before). Contractor is suggesting the following options while we have everything open:



- along with AC, put in forced hot air - driven off gas fired high efficiency unit on 2nd floor; this would allow us to create zones in the back half of the house



- other choice would be to forgo forced hot air and optimize the current radiator based system; in doing so, create zones but would be all oil fired (off current furnace)



- radiant floor heat is an option too



House is not well insulated so that is order #1. Let's assume we get that attic nice and tight.



Our questions are: is it worth going down the path of forced hot air on a nat gas system? If we do so, we would keep oil system for living/dining room (front of house). Any thoughts about the merits/disadvantages of diversifying fuel sources? Longer term, what is the utility of optimizing an existing radiator based system vs. putting in forced hot air that can heat zones more readily?



In order of price:



- Add forced hot air - modest $ over initial

- Pass on forced hot air but create zones with existing radiators - $$ over initial

- Pass on forced hot air, create zones with radiators, add radiant floor heat - $$$ over initial



Many thanks



m_b

Ironman

Another Option

Install a gas mod/con boiler connected to existing radiation. This could be zoned at each rad with TRV's. It would probably save 30 - 40% over your present setup with greatly improved comfort.



For a/c, install mini-splits where needed.



I wouldn't even consider forced air for heating when you already have a good hydronic system.



Where are you located in the Mid-Atlantic area?

mass_biker

Maryland

So - replace oil furnace with gas mod/con.

Then add TRVs to each room. We have radiators everywhere. In the large renovation areas, the old ones have gone so the big question is do we do away with radiators entirely in these areas or put in Runtals or the like (what we have in our current home). This way we utilize the same existing closed loop - am I getting that right? Never had TRVs before - what's been your experience with them to regulate the room?



Also, not a whole lot of experience with forced hot air - been a radiator fellow for ever - but the price differential made me scratch my head.



Location is MD, by the way.

Ironman

Correct

You can control the room temp. at the TRV. If Runtals or panel rads are used, they can be connected to the same loop (zone) if sized properly.



If you install forced air in a house like yours, you'll probably go from scratching your head to pulling your hair out after you've done it and have to live with it.



I'm in the Staunton VA area. There are some excellent guys on here who are in MD. "Steamhead" is near Baltimore; Dan Foley in Northern VA.

Paul48

Mod/Cons

are perfect for large volume systems.Proper sizing is critical.An accurate heat loss MUST be done. Try not to get rid of the old cast iron radiators. You won't find better heat emitters. And like stained glass, fit the house style.

neophytehomeowner

imho

I am an old guy who has lived with every kind of heat in every kind of house. These are my 2 cents.  Forced air heat is not as comfy as radiant. One thing in its favor is that house plants love it.  If you have a lot of house plants they thrive much better with the air movement that mimics natural wind that plants need to grow their best.  Also, if you are senstiive to dust you can set up a good housewide air filter in the forced air system.  Also, if you live in a high humidity area with lots of damp, slightly chilly days, forced air is great for a touch of drying heat that circulates air and can help reduce mold/mildew build up. If you are installing central AC anyway, it is a small relative cost to throw in a hydrocoil in the duct system for heat.  I would also say be careful trying to retro-insulate an old wooden house.  Many such houses when located in humid areas only still stand because they naturally breathe.  If there is an old stone basement, lots of moisture will naturally wick up into the walls.  Old houses were designed with hollow walls and a straight shot to the roof and outside to allow moisture to pass.  Fill those cavities and you may be looking at mold and rot in the future.   New windows and doors are first priority for sealing house.