Sizing a boiler

Gene Davis_2

OK, I used the SlantFin heat loss download. Free . . . I guess you get what you pay for, but I'm just trying to get in the ballpark, so I can see if the guy I chose as a heating contractor is doing anything approximately right.

Don't get me wrong. He is a pro, and the only one available to me, and I gotta trust him. But he just put in his first mod-con ever, last fall.

Here are details: In the lower walkout floor, mostly ICF walls, biggest thing going on heat-loss wise is the 6880 patio door at the walkout end of the game room. Heat losses: Gameroom (6073), Bedroom 1 (2870), Bedroom 2 (2390), bath (662). Main floor: large common greatroom, foyer, eat-in kitchen (40,772), Bedroom (4210), bath (1598).

Added all up, it comes to 58,575 Btu/h heat loss.

We want to run 180 degree water in everything, mainly because of the big room needs being so high, and wall space at a premium, we need big outputs from a combination of radiators and fan convectors. 180 everywhere means we don't have to mix down, right?

Hey, I'm not a heating pro, just a builder.

Fuel is LP. There is a gas fireplace, not figured at all in the heating equation, in the large common room.

Do we move up to a boiler with an 80K capacity? What is an OK quality gas one?

Ron Gillen

How many houses are you building?

How do you expect to get help from anyone on this/these systems? Feb. 1 - 750 sq.ft.,R50 ceiling,R21 walls,low-e glass, icf basement, -15 design, 58572 btuh. Sounds like about double what the heat loss would be. Feb. 1, another post, 444 sq. ft. 40743 btuh -27. Jan. 29, another post 574 sq. ft., -15 design. Jan. 29, another post, 750 sq.ft. If the latest numbers are correct, you need the smallest mod/con you can find and radiant in the slab and subfloor. My headers cost almost as much as a furnace. Buy yourself a nice furnace.

ALH_4

hmm

I don't understand, Gene. Why is every place so cheap?

All I can figure after all this is:

1. You dont have a heating guy.

2. You price the stuff we say will be the least expensive and then use that to needle your heating guy into dropping his price.

3. Your heating guy doesnt know much about hydronic heating or heating in general and should get some training.

Why second-guess the guy so much? Better yet, send him here and let him ask some questions if he wants or needs to. Everyone here is more than willing to help, but this isn't adding up.

Gene Davis_2

I have a heating guy

And he is the only guy I've got.

No web connection, no fax, no cell phone. He is a sole proprietor that used to be a journeyman plumber for a very small local plumbing outfit that is no longer in business.

He has drawings and specs from me, and will rely on his wholesaler, whom I do not know, to engineer the system and come up with a package of equipment.

I am simply trying to get in a position so I know something, rather than nothing, so I can discuss things when the proposal comes back.

Gene Davis_2

We are building one house

But it grew. Things looked too small for my partner's taste, so we expanded it by a couple feet in two directions.

In the market in which we are building, there are just a few small outfits building new homes, and they all are doing their own plumbing and heating with their own employees. The same employees that do the foundation building, carpentry, roofing, etc. Because real estate less remote than this is so extremely expensive, these small houses on very inexpensive land are being snapped up by vacation home buyers, who are priced out of the closer-in markets.

What I saw in snooping through these other projects, are heating systems that are simply baseboards, driven by mostly WM WGO oilburners, no radiant anywhere, and certainly no outdoor reset controls. One of the projects had no baseboards, but steel panel radiators, all with TRVs. Same boiler.

We are kidding ourselves if we think that the clientele will rush to us to buy a house with a more sophisticated heating system than the others they see.

As I have said in another thread, my only source for a heating guy is a one-man show, no web connection, no fax, no cell phone, and certainly no real background in designing and installing the better packages. A lot of his work involves plumbing service calls, not heating.

So, I am trying to gain a step in coming up with a basic set of recommendations for a boiler, a set of controls, and radiator equipment to handle the heating.

Did you see my post where I did the SlantFin download and tried to understand the heat loss, in order to size equipment?

ALH_4

options

Fair enough. Sounds like it is time for your heating contractor to move into the 21st century. Things have changed a lot in the last 7 years.

For economy I like Crown Boilers. The CWD is a nice sealed combustion cast iron boiler that is over 85% efficient. The AWI natural draft is a good basic boiler.

The Triangle Tube Prestige is worth a look for a project like this. It isn't much more than a good quality cast iron boiler once you figure in the labor savings in mechanical room piping. Ditch the baseboard for some inexpensive panel rads and throw TRV's on the system to eliminate the thermostats and wires and you can save more. Or, probably better sized to the load is the 50MBH Munchkin.

Most steel panel radiators are nearly identical. VEHA makes some that are very reasonably priced and seem to be very good quality. I did a pretty detailed cost comparison a while back and the panel rads were just a little more expensive than high output baseboard when you take labor to install the baseboard into account.

It's up to you, but I bet the Prestige system with TRV's would not cost much more than an old-school baseboard system. I always prefer to put money into equipment rather than labor.

Gene Davis_2

Let's see if the attachment function works

See the pics to understand the project.