Looking for opinions. Need to decide on one of these options. Cost is becoming a factor and am leaning towards the water heater...
Option 1 - Use a bradford white 40 gal to heat two zone wirsbo in bsmt (68 degrees because not planning on finishing it off for quite some time) and garage (50 degrees). Bsmt is 1100 sq ft and garage is 800.
Option 2 - Use a Buderus wall hung for above configuration with the addition of a Amtrol hot water tank for domestic.
DualZone if you can do it use the Buderus, if you can afford it. Another thought, maybe look into the Quietside boiler. It does DHW and can be used for your in floor heat. It has limitations on the DHW output however. But, you can add a tank to make more hot water. The water heater you are talking about will work, I have used them many times,but, it is very ineff.LOL
Go with a boiler, fuel costs will probably be 1/2 of a w/h. NTI Trinity is another option.
A.O Smith makes a water heater that is called a Comby core, or something close to what I wrote. This is designed for this application and you can use it for domestic hot water, and infloor heat. I also believe it fires at about 75,000 BTU's versis 35,000. I have installed conventional water heaters for this application but it is going yo take a long time to heat that much slab. I agree with the previous posts, install a condensing boiler so you can run it at 140 degrees without installing a direct injection or some sort of mixing system. Some of your options that I have installed in this situation could be; Munckin, Dunkirk Quontum 90,Burnham Revolution,the Budreus somebody else sugested, or I know they have some wall hung units available, but I have never installed any of them as well as the Budreus,