Tankless Water Heater

My home is currently heated with a natural gas 65 gallon hot water tank to infloor radiant heat. Will replacing this tank with a tankless setup work with infloor radiant heat. My understanding is a regular HWT is about 65% efficient and a tankless is about 90-95% efficient. As my current tank only comes on when the water in the tank needs to be heated which is several times per day during the winter and once per day during the non-heating season. But if a tankless unit was installed it would turn on ever time the wall thermostat calls for heat which would be many many times per day. So in the end are you really saving money by using a tankless over a regular tank with infloor radiant heat? Mind you during the non-heating season the tankless unit would rarely run in our 2 person home, just for the odd hot water use. Thanks for any info.

 

I'm lost here. Could you post some sketches and photos of your system?

 

The member is from Canada and Canada is listed as a location in bio instead of non US.

I understand what he's saying but it doesn't sound correct. You can't use a water heater set up for domestic hot water use for radiant heating.

There is no way you would be running domestic hot water through the floor radiant heat.
There would have to be some type of intermediate tank.

 

Sorry about my confusing post, basically my question is can my current 65 US gallon direct power vent natural gas hot water tank that is used with my infloor radiant heat system be replaced with a tankless natural has hot water tank. See images for layout. Not sure if a tankless unit is designed to work with this type of heating or if the tank I currently have is a better option.

 

You said this:
I have no idea how to respond to that.

 

Man i am losing it lately. Forget it. Thanks for trying.

 

I came across this.
https://www.youtube.com/watch?v=vffdymvjluk

 

Selected this tank for replacement of my 18 year old John Wood that finally gave up yesterday. Being used to work with my infloor radiant heating system.

http://www.giantinc.com/tech-data/GI-PB021En.pdf