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radhazjoe
Replacing boiler with central heat and air

My son has a house in Cambridge Mass. Old with 3 stories and boiler in basement. Window AC in most rooms. And ideas or products that would facilitate replacing with central heat and air would be appreciated. Running ductwok upstairs is problem. We thought about using removed chimney stack. Ceilings on first floor are very high and could be dropped to accomadate lateral ducting.

dj1
Re: Replacing boiler with central heat and air

Invite a/c contractors to evaluate your situation and suggest ways to improve it, because this is not a DIY project. You'll be suprised with their inputs.

To find a/c contractors, you will have to ask around and get feedback from family, neighbors, friends and other recommending sources. In other words, contact only those with proven track record. Don't waste your time with BBB, paper ads, phone books with full page ads, flyers and these kind of sources.

Winter is a good time to install central a/c, While demand for cooling is very low.

Good luck.

Brookworld
Re: Replacing boiler with central heat and air
radhazjoe wrote:

My son has a house in Cambridge Mass. Old with 3 stories and boiler in basement. Window AC in most rooms. And ideas or products that would facilitate replacing with central heat and air would be appreciated. Running ductwok upstairs is problem.

I'm a DIY novice but learned that (paid) pro's only get it right half the time, so weekend guys probably get it right even less. Another life experience is when you shop, a business is very likely to sell what they have and not what you need. You end up making your own decision but let others validate it.

It seems to me that this is a project that will be big bucks unless it's part of a major renovation where other things are being done. I thought I'll throw out 2 ideas just so you'll know about them, and maybe is a test for how professional your contractor is in advising you.

One is mini-split A/C or ductless A/C -- I describe it as a giant car A/C system -- it's great for cooling big spaces but poor for individual rooms because you can't get a special air handler (front end blowers) in every room. Heating is available but works only when outdoor temps are above 35 and electric heating is expensive.

The other is the Unico system which is a 3" duct system using high velocity air, but the ducts can go in very tight spaces.

Both are very expensive systems but in certain conditions, are the only choices and can work well. They are generally not cost effective if there is already existing duct work.

motoguy128
Re: Replacing boiler with central heat and air

High velocity or mini split is the best way to go. IF you have natural gas, mini split with a gas furnace will be a little cheaper to operate. IF you only have electric, then go with a mini split. The better mitsubishi and hitachi units perform excellent at low temps.

Miniplits will offer the best zoning, dehumidification and overall comfort. High velocitiy systems MUST BE DESIGNED correctly and installed correctly. or thy will be noisy and heat and cool unevenly.

bconvers9622
Re: Replacing boiler with central heat and air

A split system is always the way to go for A/C and the best heating quality. If your boiler's hydronic, keep radiant heat where it's needed and add a zone or two for one to two air handlers. these units are similar to furnaces, except they use hot water as heat instead of a gas or oil flame. If your starting with a boiler, keep the foundation of the system the same. In other words, don't change to forced air. Two reasons: It's a pain to route ductwork, and steam and hydronic heat are the most efficient types of ways to heat. (depends on the boilers efficiency too). if you can keep the boiler and it's system, just add air handlers for A/C. I would never replace a boiler with hot air.;)

jled96
Re: Replacing boiler with central heat and air

It is possible to do what you want , but I have just done this and I can't say it was worth it. I had a 90yr old steam system with a 12 year old burnham steam boiler which was very neglected by the previous owner, I tried for 3 years to get this steam system to work efficiently and everytime I had someone work on it they told me to bring everything to the scrapyard. Now that said, I think the steam worked better by providing an even heat and warmer feeling enviornment, if the boiler did not start leaking water up the chimney I would have kept it for as long as I could. A replacement boiler was very expensive and they were not very efficient. I went to a 96%efficient furnace with 21 seer a/c and it has been o.k., if my system was designed better it would probably be more comfortable, So if you choose to do this make sure you get a contractor who addresses all of your concerns and double check all the supply and return air sizes as well as the heating and cooling btu's to make sure they are right for you sq. footage.Good Luck

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