GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Concerns about installing a condensing modulating boiler with an indirect hot water tank in a turn-of-the-century house

J Chesnut| Posted inMechanicalson

First, I want to check if there are any red flags about installing a condensing modulating boiler w/ indirect hot water in an old home with cast iron radiators in Minneapolis. I need to add an additional zone for a previously unconditioned space with plumbing. There I am planning to add a single wall hung radiant panel. My understanding is the cast iron radiators typically operate with water temps at 180 degrees F, the wall hung radiant panel at 150 degrees F, and the hot water will be heated just above 120 degrees F. Is it a problem for a single modulating unit to supply different zones with different temperature demands? Would there be different temperature demands?

Second, is it important to select a modulating unit with a low MBH output so that in the summer when the unit is only supplying hot water it is not using more energy than a well insulated gas fired water heater with its own burner (40 MBH output typical)? If yes, how low?
I live in a frugal household – 2-3 people, 1 shower, 3 sinks, washer, no dishwasher use.

Lastly any experience among the brands of condensing modulating boilers and indirect hot water tanks? So many brands on the internet, I imagine there must be some quality differences in the hardware. Also anyone know of an indirect hot water tank insulated with more than 2” of foam?

(Any recommendations on a free web based heat loss calculator?)

Thanks,

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.

Replies

Log in or create an account to post an answer.

Community

Recent Questions and Replies

  • |
  • |
  • |
  • |