Small boiler requirement

Gene Davis_3

For the small house we are designing, my calcs show a total heat loss of only 37,200 Btu/h.  I used SlantFin's Hydronic Explorer 2 for the calcs, design temp of -20 F. (northern Adirondack region of NY, it was -25 last week in Saranac Lake), and good modern values for thermal transmittance in walls, windows, roofs, etc.

The house is a story and a half, less than 1500 sf total, but with a large vaulted ceiling space and high windows over the common greatroom areas.

I believe we need a small mod-con boiler with the ability to turn down to an output in the 15k or under range.  Heating will be done with panel radiators operating at 160 F.  The house is a vacation home, and will typically be occupied from about August through October, with occasional week-long visits in the snowy wintertime.

The great room with house a wood stove, which will be the preferred heat for the fall visits, with the ambience of a fire enjoyed, and only a little heat required for the house on chilly mornings.  The boiler will see a whole lot of idle time.

DHW will be done with electric units, two small shorties in parallel, shorties because they will be in the crawlspace with 48 inches of overhead.  They are inexpensive, require no boiler piping and controls, and since most of the DHW needs are during when the house does not need heat, it seemed better this way.

What boilers should we be considering?

Charlie from wmass

DO not write of an indirect

Gene an indirect will keep the boiler working in the off season. This makes for a more reliable heat source. We are leaning toward the major stainless steel brands at this point. I like the Buderus but I am shying away from aluminum. A subject of many other posts is the debate over aluminum. It comes to water quality for all the boilers.

CMadatMe

Type of Boiler

I believe in a previous thread you stated that you were using a Viessmann Vitodens 100. You may want to look at using the small Vitodens 200. Since this is a vacation home and panel rads also use the Vitotrol 300. It will give you day and nightime temp, DHW Temp, holiday program and part and energy-savings features. It will also allow for switching times for your heating circult, DWH tank and a recirc pump if you choose to use one. I would stick with an indirect. You already have a high efficient piece of equipment making the energy why make more energy with electricity. I would also get the phone module. Nothing better than calling up the boiler on your way up and having the house and domestic hot water ready to go when you get there.

Gene Davis_3

The Vitodens 100 was shown for space sizing only

In my 3D model to study space for a boiler, I used the Veissemann because its size specs, h x w x d, was readily available to me.  I thought it might have a size typical of wall-hung mod-cons in the same range of capacity.

With my relatively low heating needs, it seems as if we may want something more like the capacity of the Triangle Tube Prestige Solo 60, with its specs for input modulation of 16 to 60 MBH.

The points made here about indirect for DHW are good ones, and now we are rethinking the scheme to include it.  See the pic attached.

We've a good local distributor for the Triangle Tube line.  What might it take to get telephone control for this one?

CMadatMe

The Triangle

Control does have 0-10 OV on the terminal strip for external demand. I may be wrong but I believe you would be giving up the boilers control and have to come up with your own control for modulation and phone access. Contact that distributor they should be able to give you the anwser.

SpeyFitter

Lochinvar Knight WB050

Is worth a look - modulates from 10,000 to 50,000 input.

I think you are mistaken if you are not going to use an indirect. Much more inexpensive way to heat, and most mod-cons mentioned have the built in controls to do the job as well. Lochinvar offers a 30 Gallon Squire indirect that has pretty good output when teamed with the WB050 mentioned above for its size.

IBC 15-150 is another option if you want something that can crank out the heat in a big way when they decided to arrive and turn the temperatures up (modulates from 15,000 to 150,000, and if teamed with a 30 or 40 gallon low height indirect HWT could give you probably unlimited hot water for that size of place).

Also the TT 16-60 as mentioned, or the next Lochinvar Knight which does 16-80,000

bob eck

small boiler

check out Triangle Tube Prestige Excellence 95% AFUE boiler with 14 gallon built in stainless steel indirect water heater that delivers 180 GPH of domestic hot water.

This is a boiler and water heater all in one model.

stainless steel heat exchanger + stainless steel indirect water heater + vents with PVC pipe + outdoor reset control + when there is a call for domestic hot water it gets priority over heating zones + 30,000 - 110,000 btu on nat gas or 25,000 - 97,000 btu on lp gas + 95% AFUE

great boiler check it out.