What you have described is a very elaborate and expensive hot water system. What are your priorities? Is it producing hot water at the lowest cost, or supplying a large amount of hot water?

What is your natural gas rate and how many people will be living in the house? You are proposing a system that is so expensive that you will never see a return on your investment.

Thanks much everyone ! Another reason that got me thinking along these lines is to do space heating using the hot water. What I was thinking of was to use a heat exchanger on the pipe coming back to the tank and use that to heat the home (though forced air). I have to admit I haven't done any calculations on the effectiveness of this, but it is just a thought. Space heating does cost a good bit (we run the heater about 7 months of the year). It is clear/sunny most of winter. Besides, my dad prefers to keep the house at a toasty 78 resulting in high energy bills.

What I imagined is that I would get most of my space heating bill (about $1000/year) reduced this way.

You said: What I was thinking of was to use a heat exchanger on the pipe coming back to the tank and use that to heat the home.

Not sure where you live, but in some places, the Code requires that all hot water pipes be insulated. Plus it takes energy to run that recirc pump 24x7 etc It might be time to talk to some of the pros who install this to see what makes sense.

BTW I just googled "heat your home using solar" and got a lot of hits. Maybe start there.

Joe Macker

The right answer is to look at your entire situation - insulation, efficiency of your current heat source, the cost of various types of energy (natural gas, electric, etc). and possibility of alternatives (how practical is solar).

Insulation and a 95% gas furnace, for example, can cut a lot off the cost of heating - without getting into exotic technology.

Don't start with a solution - start with a clear understanding of the issue and what you want to accomplish.

The right answer is to get someone who understands what you want and how to go about it . To me this seems very complicated for no real reason. Forced air by nature is forecedAIR not water if you want hot water heat that needs a boiler there is not a way to have enough hot water to heat a house in my experience that requires an actula boiler. I have solar heat for my pool with back up heat to extend the season that runs from my boiler that works fairly well since when I need the heat for the pool I don’t need it in the house.

Joe,

If want ideas how to reduce your heating costs, then you need to post more information. Your location, size of house, new build or old house, natural gas availability, and utility rates would be helpful.

The simplest solutions are the best. If the equipment configuration becomes complicated, then you create a long term maintenance problem.