Domestic hot water storage efficiency

ecky

I was hoping to use a 5 gallon electric hot water tank with a heat exchanger from an outside boiler. The idea is that the 5 gallons would allow for the initial requirement for hot water while "waiting" for the water from the outdoor boiler to arrives A heat exchanger capable of 5 gpm would then take over providing enough hot water to keep up with the needs. A 5 gallon hot water heater would be used in order to limit stand by losses as opposed to heating a 40 or 60 gallon standard hot water tank. I am hesitant to use an instantaneous hot water heater for several reasons (cost, electrical requirements, reliability). Any thoughts?

Gordy

If your wood is free

I do not see being anal about stand buy loss of a larger vessel. It all depends on how much hot water you use in a day, and frequency though.   At least you have the hot water when you need it.

ecky

Amount and frequency

It is not so much about anality - as efficiency. :^) You certainly brought up valid points about how much water (only 2 of us - water wise users at that) and frequency. Never during the day for DHW Monday to Friday. But certainly use during the day when the heating system is running. Thanks for your input Gordy.

Brad White

Bulge in the Pipe

I agree with Gordy, storage losses or rather anything you save by say, adding insulation to an already well-insulated tank, is easily spent in one good shower.



The benefit I see to the 5 gallon tank (provided it is charged and ready), is so that you can wash your hands or rinse a glass without triggering larger generation sources. If this is in line to a large user (your main bathroom or kitchen), there is enough small use there so you can draw a trickle without penalty.



It really is a bulge in the pipe though.

TonyS

Gordy Gordy

Isnt that what always gets us in trouble? When something is free or cheap that does not mean we should just flagrantly waste it. Wood is never free, you could always sell it.So in reality you are throwing money away.

But then you are talking to a guy who refuses to send his kids to school on a HALF DAY.

. I write letters to the school telling them I will not participate in the stupidity of starting all those buses and burning all that fuel for 3 hours of school. Funny how liberal green teachers lol dont seem to care about that. Who knows, maybe I am anal  lol.

Brad White

Tony

I like your thinking!

Jean-David Beyer

Half-Day schooling

I am also opposed to it because of the waste of running the busses for such little benefit.



But there are considerable other costs as well, apparently not perceived by school boards who authorize this. School boards fail to recognize two large populations; both are parents of the students.



One is the parents both of whom must work during school hours. It is bad enough that the school hours are shorter than normal business hours, so the parents incur expense to arrange for day-care of their kids after school. School boards seem to think that this is the 1940s when it could be presumed that the mothers stayed at home and were always available to take care of the kids when they were not in school.



The other is  the single-parent families where the single parent must work and usually cannot possibly afford day care. If they take too many half-days off, they can lose their jobs, and then cannot support their kids and may lose them too because social services agencies consider not supporting your kids to be  abuse. Bad for the parents, bad for the kids, and a serious expense to the county or state.

ecky

A little off topic but valid comment on the environment and schools

In our area, their are 2 separate school boards. They can't even get their act together to have PD (Professional Development ) days for teachers at the same time. There are even discrepancies between elementary school days off and secondary school days off within the same board. Talk about a waste! The school buses end up running the same routes pretty well every day of the school year because of this "disconnect".

ecky

Bulge in the pipe

Brad you bring up a good point but perhaps miss another. The 5 gallon tank would likely prevent triggering the system for all the dribs and drabs of short small washings as you stated. You and Gordy are likely correct on your assertions that the standby losses would be negligible. However it would also likely mean a lot less water would be wasted as I wouldn't have to wait for hot water to arrive from the boiler. As Tony said - pretty well everything comes at a cost. My two cents. Thanks for your input.

ecky

Waste not

Excellent points - both. Well stated Tony!

Brad White

Dribs at the next level

ecky, the logic scales-up to when you have a stronger draw and I should have made that clear and stated it. That five gallon bulge can allow about 2 minutes of shower time during which time your main source comes to the rescue. Your line recovery (a timed, occupancy-driven or manual twist switch recirculator!), would get that charged ahead of your shower to avoid a cold sandwich.  The tank is a tool to be used.

Gordy

Tony, Tony!

I too should have been clearer. Not trying to imply burner up its free. My point is that the larger vessel is not wasting that much more energy, and you have the hot water when needed. For most people this is of most importance. I did say this depends with their usage not knowing they were very frugal with their water needs also.



As for the wood being free yes you are right you could sell it. Its a commodity.



 I like your stance with the school system. I too feel the same way. The kids are out now so it does not effect me as much except through taxes......Uh mm yeah still effects me as much.  Wonder if it ever got anyone to do an analysis.  I'll bet now more than ever.

Gordy

School buses

 Since we went array with the thread, and still in healthy discussion of a worth while post. Do any of your school districts run the buses all night in lew of sub zero temps so buses are up, and running for the following school day?



 If things are that bad call it for cryin out loud. It does not only happen maybe 3 times a winter. But thats a lot of buses idling all night.never counted but its fifty or so.

ecky

School bus idling

In my district, I can not say for sure but suspect that the buses are not (thankfully) run all night long.

ecky

School bus idling

In my district, I can not say for sure but suspect that the buses are not (thankfully) run all night long.

Charlie from wmass

The thing is though

I agree with you Tony but they are still burning that fuel if your kid goes to school or not. The regulations seem to be if they are in school more than half the hours of a full day it counts as a whole day, at least in the districts I have had to deal with. The only people I see that can waste wood are sawmill owners. It is cheaper to burn than dispose of the sawmill waste.