opinions re: tapping off a new boiler for domestic hot water

[danny burstein]

Iffen I can ask for some opinions and experience from the pros here:

We recently had our local, licensed, experienced, and qualified professional installer replace our 15 or so year old natural gas boiler with a Lochinvar pretty high efficiency unit with direct through-the-wall venting for .

(multi zone, hot water baseboard heating).

While payback is quite a few years, I just have this built in opposition to giving a utility any more money than absolutely necessary.

He's suggested that we could tap into the unit and pull our hot water from it. This would be more efficient than what we've got now (a standard NG unit from about ten years ago), and would let us seal off the flue - thus helping even more.

This model is designed to handle that secondary coil deal with straightforward connections.

While it would take more years for that payback, it is a bit tempting...

Any thoughts? One of my biggest concerns is the reliability issue - I'd hate to lose both heat and hot water if something hiccups on the system.

Thanks.

[Steve]

what about having to run the boiler in the summer for hot water??

[danny burstein]

It's a high efficency unit that varies the flame size/duration as needed (and has all those other nifty design features.)

So it won't be pumping out 100,000 BTU/hr when all it needs is enough to keep the water coil hot.

[John Gilmer]

Using domestic "boilers" (does the original poster have "steam heat" or hot water heat) to provide all season hot water has been an option for most of the 20th Century.

In winter, it's almost a nobrainer. In summer, the same inefficiencies you have with your gas hot water system will manifest themselves. In particular, even if the circulating pump(s) is/are off, you have a good sized tank of hot water sitting in the basement losing energy, heating the house, and increasing the load on any air conditioning system.

I "assume" there would be a tubing coil inserted into the "boiler" so that your domestic hot water isn't contaminated by whatever your plumber left in the heating system. The "boiler" produced hot water would also require a good mixing valve and an aquastat (which it may already have) to keep the domestic hot water within comfort range. If the "boiler" is left on during the warm months then using it for domestic hot water is a 4 season no-brainer. If you decide to turn it off during the summer you still need a domestic hot water heater.

You might look at heaters that can "vent" through side walls (these have an auxiliary blower) as well as demand based heaters can can also vent through side walls. The latter would not heat your basement until there is an actual demand for hot water.

Frankly, you might be better off with your separate hot water heater and keep the two systems separate. If you keep your conventional gas water heater with a stack vent you will have a small but very reliable source of heat (your hot water) that doesn't depend upon electricity.

That might come in very handy some day.

[zekor]

Boilers make steam and use one pipe to the radiator.

Get that clear !!!!

greg

[Tony Hwang]

Hi, I thought boiler water contains some chemical, No? Is it just pure water?

[.p.jm.]

Many steam systems use TWO pipes.

Get THAT clear :-)

[zekor]

malrescuesite.com/

Also tend to click, bang, and go ssssssssssssssssss

A steam boiler will collect minerals just like a hot water heater. The system usually needs adding water at intervals.

greg