40-50k btu boiler?

maitoboika

Wondering if anybody has experience installing smaller boilers, or know of any decent ones? The system is about 40,000 BTUs, with 7 panel radiators. I was planning on a Viessmann Vitodens 100w B1HE-85. I’ve been having problems finding a boiler with a smaller btu output.

DJS

lochinvar whb055 or whb085 depending on what your supply water temperature is. If it's 180 degrees the 55 might be light.

Ibc sfb99-1 works great too.

Most boiler these days can set a max output or have ramp delays to allow you to not be super oversized.

I just put a IBC sfc125-1 in my shop and only need about 35,000 btu's for heating and the rest is for DHW. I set the max heating output for 45%(the heating side is maxed at 99,000). But I'm also only heating the floor temp to 85 degrees.

mattmia2

The better question is what the minimum load is. Most mod cons can operate at a bit less than their max output without a problem but the higher max output means that the min output will also be higher and that could be a problem on a system with a small zone.

kcopp

The IBC HC will get you between 13k and 50K

I have a bunch out there. Very reliable for me.

hot_rod

I have a Lochinvar Knight 55K, 51,00 output. It modulates down to around 8,000 BTU/hr. It has nice control features.

With panel rads you should not need much above 140- 150°