Help with forced air system/HW!
Hi - very basic questions here from an HVAC learner. We're adding a 2nd floor to a 1950 cape with recessed hw radiators and oil heat. Looking for a bit of advice re the new system.
We didn't want to remove the radiators (we like the heat) on the 1st floor, but based on the fact that
1. the low hanging pipes in the basement that have to be moved are heat pipes
2. that the first floor changes would require relocating 3 radiators,
3. adding ac ductwork anyway; and
4. the radiators have 2 coats of paint on them
we are looking at forced air. Also converting to gas.
Question 1: I once had a forced air furnace and it was a cycle of huge noisy windy blast of heat and then a slow cool. and dry. Hated it. Are they better now? what should I look for in a forced air system to avoid this?
Question 2: what hot water system is best with a forced air system? I never want to have the amount of hot water be an issue. Tankless? There will be 3 full baths.
Thanks for your advice. much appreciated.
Southern CT, Fairfield county
Last edited by kremlin; 11-10-2007 at 02:37 PM.
First off, where are you located?? We can direct you to someone in your area on here who can help you personally.
Forced air systems are as good as the design is. Starting from scratch a competent dealer (hard to find) can design a great duct system, add zoning, air cleaning, humidifying... But this dealer will not be cheap and a cheap dealer probably won't do a good job.
The heating system does not determine humidity in the home. Infiltration does. Again starting from scratch with the upstairs, built it tight to keep outside air out (foam insulation, lots of caulk) and you won't have a humidity problem. Leaky house, you'll need the humidifier.
Tankless hot water probably would be a good suggestion.
thanks. southern ct. fairfield county
Originally Posted by seatonheating
BaldLoonie - concerned about cost of course, but understand that good work is wirth the extra money. The upstairs will be tight.
As to hot water, will one tankless be enough? can 2 be run? i've heard of issues with flow from tankless.
Unless all 3 tubs wanna fill at once, you should be fine with 1 tankless. Another choice is a big 75 gallon tank type.
With today's PEX tubing
No reason why you can't relocate those rads, or put in some stylish panel rads or high end baseboard. You can snake the PEX tubing almost like electrical wiring. Get a modulating /condensing gas boiler with an indirect HW tank. Run tubing to the new floor and do all the zoning you want. You make it much easier and simpler to design ductwork for AC only. In the north east we got the heat on 1/2 the year. Why would you give up the best heating system there is: hydronic heat.
As noted, I like the radiator heat, but the factors against it are the cost of moving the pipes in the basement, somehow refinishing the existing radiators as they have several coats of paint, cost of relocating first floor radiators. Just the fact that we would have to refinish the existing radiators would seem to be enough of an issue.
Is forced air really that bad? I've only lived with it once for a few months and the system was horrible but I understand that things are much better with 2 stage furnaces, variable speed air handlers etc.
If we do go with forced air, I'd love some advice on hot water!
Thanks all for your input!
you're just listening to the hot air HVAC guy. Sad, you'll be sorry. You're going with the less efficent heating system. Just get a 40 gal. gas water heater. Cheapest thing you can get.
Hydronic offers a level of comfort that hot air can not. Pex tubing itself is economical and pex can be run in most places. I wouldn't give up this kind of heat myself.