I am looking to build a new home or purchase a Stick built Modular home, and I am looking for a way to heat it.I have looked at a corn furnace and Pellet stoves but I have decided I want Radiant heat.
What is the best most economical way to heat the water? I have read that some people use a hot water heater,while others say you should never do that etc...... The home will be approx 1300 square feet R21 in exterior walls and r 49 in ceiling. building in upstate NY, cold winters.
Thank you

Hi,

I have recently built a house in the general area (Fingerlakes region).   The square footage you list is too small for a mod/con in most situations.  It depends a little bit on what else you need hot water for, but a regular hot water heater w. an exchange valve is the most likely choice for you; you will be able to address both DHW and heat w. the same appliance, and the "stand-by" loss that people usually experience with hot water heaters will be minimized because you will be using the hot water tank's stored heat for the radiant system much of the time.  You could also use a tankless system, but other threads on this forum contain arguments against that approach.  I think those arguments generally make sense.

I disagree.

Unless you are talking about using potable water for radiant floors and domestic hot water (never done by code), you will need a CombiII. A Mod/Con at say 50mbtu/h input would just be fine as it will modulate down to the load I expect you have, include outdoor reset - further lowering you fuel bills - , make you more comfortable and cost less.

A heat load analysis would be the first thing.

An indirect made as small as 32 gallons would be the perfect match.

Standby losse are nothing compared to the 60-80% thermal efficiency of the average water heater, not counting of course the open flue and requisite combustion air.

I'm not an expert - you likely are, so I'd say cove314 should weigh your opinion more heavily -- I was thinking mostly about the install cost -- my impression is that mod/cons are expensive installs, and with only 1300 sqr, it would appear to be a long recover period (but still, likely more efficient in the end --?)

Your point if well taken. Where loads and mechanical rooms are small, I often use the Bradford White Combi II.