Replacing a New Boiler

Bethbeth

HI
I have a 7000 square foot house. My boiler is 22 years old. I have 4 new air handlers and radiant heat in the basement (approx 3300 square feet not counted in the 7000 ) What size boiler do i need...... also what is the 4 section versus 6 section mean when buying a boiler

jesmed1

If you have records of your house's heating fuel consumption, this method is very accurate for sizing a new boiler:

https://www.greenbuildingadvisor.com/article/replacing-a-furnace-or-boiler

Also, if you can mention where your house is located, when it was built, what type of insulation it has in walls and attic, and what type of windows it has (old wood double-hung with storms, or modern double-pane), that will help give a ballpark idea of what your heat loss is.

You might also want to post a pic of your boiler's "rating plate" that has the BTU ratings on it. That gives people an idea of what you have now for heating capacity. Which is not necessarily the size that you actually need. It's probably already oversized unless you've added major additions to the house since the boiler was installed.

KC_Jones

Bethbeth said:

HI
I have a 7000 square foot house. My boiler is 22 years old. I have 4 new air handlers and radiant heat in the basement (approx 3300 square feet not counted in the 7000 ) What size boiler do i need...... also what is the 4 section versus 6 section mean when buying a boiler

A Manual J heat loss calculation needs to be performed on the building to be able to properly size the boiler.

The sections of a boiler are a literal description of how many casting pieces make up the boiler. It give a rough idea of boiler size, but in reality it's about the BTU capacity of the boiler. The heat loss calculation is compared to the boiler BTU rating to select the proper boiler size for the home.

HVACNUT

If I had 10K sq ft, I'd be paying someone else to do the math while I'm sitting poolside sipping Mai Tai's. 

But, yes, heat loss calculation as mentioned. 
You listed air handlers. Does that mean they have hydro coils (warm air heat)?
If so, the sizes of the coils are important as well. They need to be able to deliver (X) BTU's at (Y) CFM.

tim smith

Heat loss! If you get quotes and they don't mention heat loss and do one, move on to next one.

EBEBRATT-Ed

If the contractors, you are getting quotes from do not do a heat loss.....move on and find someone else. Post your location someone may have a contractor recommendation..