Water Heater

Topic: Water Heater (Read 1414 times) previous topic - next topic

Water Heater

October 15, 2009, 02:03:42 AM

Well, looks like my old water heater is checking out.
I am fairly certain the tank is leaking from up top where the in/out lines are as the drain nor the tstats are not leaking.

Its brand name is "JACKSON" and apparently they have not been around for approx 15-20 years.

I will be hard pressed to find a replacement with the same 400PSI tank rating. I suppose that tells us the quality / thickness of the tank. I have a bunch of older but good appliances from 1977 when the house was built.

We are thinking about going to a tankless system and I am wondering if leaning towards Stiebel Eltron is a good choice.

Electric only, no gas

We are looking at the Tempra24 plus,, pretty much twice the cost of the traditional electric tank heater.

I suppose its a good idea to think about zig zagging my water line under my tin roof on the house as a pre-heater to get the input rise higher so the heaters work even less.

A couple years ago, i meaasured my temperature under the tin roof during march and this is what i got.... when it was about 40 outside.
From what I can tell by my shadow, this picture was taken around 10-11am and i am only reading under the edge of the roof. I wonder how hot it is under there towards the middle.

FYI, my original roofing is still in place,
roof is 2x6 tongue / groove
2'' styrofoam
tar paper atop the foam
30year shingles on top of everything.

I just layed 1/2'' x 4'' x 20' long oak strips on the roof and nailed them down with Barn Pole nailes. Next I attached my tin to the oak strips. there is a decent air gap up under there.

Water Heater

Reply #1 – October 15, 2009, 10:25:02 PM

I put myself through college building swimming pools, and one of the options was a roof mounted heat exchanger for keeping the pool open and useable longer and earlier. That means nearly year-round down here, and if you have a bubble for it, it DOES mean year-round. But, I digress.

There are LOTS of roof mounted heat exchangers that do an excellent job, especially with electric heat tanks. If you have total electric, I don't know that I'd go to tankless system if I were you. It might wind up being a thankless system instead. Some are pretty intelligent systems so that if the water is warm enough, it will bypass the tank for whatever's using it. If it cools down enough, then it will serve as pre-heated water to the tank, making a smaller tank last longer. In summer you probably wouldn't even need the water heater. Some systems circulate the water from the tank through the exchanger to maintain the tank temperature. This obvously requires a separate pump, and to me, that would make the energy savings somewhat questionable. If you have a wood burning heater, it might be as good a time as any to invest in wood fired water heating too. Useful in winter, but would probably be more efficient to just use electric in the summer. Certainly a lot less work, and no unneeded heat in the house.

Water Heater

Reply #2 – October 16, 2009, 01:37:19 AM

The Tempra24 is on the way , delivery confirmed tomorrow. My two 60A ckts installed and plumbing complete. its been a busy past 6 hours.

Here is the link http://www.e-tankless.com/products.php

It was suggested I get the Tempra24 instead of the plus version because there really is no gain other than another part that can go bad. I like simple.

Now i expect real time water heating to occure well beyond my timer i installed on the old tank. With our old tank, the power was shut off 1/3 of the day and over the past few months, I saw a drastic difference in power consumption,,even with power rate hikes. with this system I will follow up with you all about the comfort of the water temp.

My next step is to increase the incoming water temp to further reduce the power consumption required to heat the passing water. As it stands now, I can expect a flow rate of 3.5 gal/min of hot water at a given moment. The washer stays on cold , the dish washer has its own water heater, so the only hot demands I have are bath / sinks.

Water Heater

Reply #3 – October 16, 2009, 10:42:58 PM

Tempra24 arrived today. I made my final connections and tested the system.

VERY FRIGGING HAPPY so far.

Now, to compensate for not having a tank, you must experiement with worse case scenerio by using hot only
on mulitiple fixtures until the tankless system starts to flash . The flash means you are exceeding the flow of the
units ability to heat all that demand.
In return, the unit will not heat all the water and you get some fluxuations of warm to hot.

I tuned my upstairs tub hot which was the only demand that needed attention. The flow on the tube is prob somewhere
above 3gal / min. Adjusting the tub water supply valve allowed me to maintain hot water.

I took clamp on amp readings and got approx 45A on L1,L2 of ckt 1 and the same draw on L1 , L2 of ckt 2.

So far so good, not many parts to go bad in the system plus I have already tested my support team and sales staff.
All of them speak english and are very very interested to follow up with my results and supply pics of the install.

I ordered the system at approx 650 bux plus 100 bux overnight shipping.

I spent 212.00 dollars on installation materials:
80' of 3/6awg
two qtr turn cut off valves
1 section Cpvc 6'
two 3/4'' Cpvc to female NPT
two 60A 2p breakers
1 container of 3/4'' wire tacs
2 washing machine hoses

see before and after pics............. I was not too happy with the way I had to run in the line feeds but it is inside rated wire.
I was shooting for some sort of wire mold but none at lowes in the metal form was wide enough to accept the wire I had.
Also, they did have plastic wire mold but that really did nothing for protecting the wire.

Water Heater

Reply #4 – October 16, 2009, 11:07:23 PM

yep, not a lot of parts in there....

Water Heater

Reply #5 – October 16, 2009, 11:27:51 PM

well,, there are more parts than a traditional water heater for sure. But still, pretty simple operation.

If i can get my rise temp up above 55 deg, then im really saving a ton of cash on electric per month. The sales guy said he kept his old hot water tank in place , stripped it of insulation and used it as a pre heat storage tank. the metal tank would absorb room temps and get the incoming water temp much higher than from the ground like me.

We will see, stay tuned for any troubles on the unit, unbiased reports only.

Water Heater

Reply #6 – October 25, 2009, 01:35:32 PM

yesterday i groomed in 100' / 3/4'' of the best garden hose Lowes had for sale up through the second floor and up to the roof under the tin. (contractor hose)

The temp under the roof exceeded 130 degF often. The goal is to get the incoming water temp to a higher value so as to produce more gal/min as well as use even less power.

The 100' 3/4'' of additional plumbing helped *some*. For approx 5min, my faucet ran water at 78degf but quickly droped inside of two min to approx 56.5.

From the well, the water temp is 52.2. A realistic gain of 4.3deg for my hot water input temp. Not to much to brag about especially when i had higher expectations of atleast 60-65deg input temp.

I am going to tear our the hose portion and keep the hose since our old one is patched up anyway (55 bux more to this project).

I am going to purchase a bulk spool of black 3/4'' pvc to the tune of apporx 500' and groom that into the water system. I would rather stick with cloth braided high grade rubber hose as it bends easier.

so far, the system is operating perfectly and i have no complaints. I am just taking some time to learn how to get my temp rise up to a temp in the 70's which will result even less power useage.

Current draw at 77deg incoming water temp is
ckt 1= 23A
ckt 2= 27A

Current draw at 56deg incoming water temp is
ckt 1= 43A
ckt 2= 37A

huge difference if i can get some longer runs of water storage up under the roof to preheat.

Id like alternative materials suggestions if anyone of you plumbers can help.

spool of 500' Copper tubing- would break the bank
spool of 500' pvc tubing- too stiff but could use if its a good idea
more water hose- cant find any longer than 100' but i works great. This would also add to the qty of splice points which i dont like.
50 sticks of pvc / fittings - this would add to the amount of splices/leaks that could happen.

not sure what else. to use or what to do.

here is a pic of my temp under the roof i took yesterday. This has really turned out to be a pretty fun project. I am keeping reciepts for next years tax's.

Water Heater

Reply #7 – October 26, 2009, 01:27:17 AM

I don't suppose you could fit a couple(Or even one) 10-20 Gallon plastic tanks of any shape up there could you? That would run most showers nicely I believe. Doesn't need to be a water heater tank.

Water Heater

Reply #8 – October 27, 2009, 12:15:33 AM

i guess i could if that were the goal.

we dont want any restrictions like that, imagine telling the wife / kids they have to take 4min showers:rollin:

I am just trying to raise the input water temp to the unit.,, thats all.

Water Heater

Reply #9 – October 27, 2009, 02:49:39 AM

Correct me if I'm wrong, but having 20+ Gallons of preheated water on tap would lower the energy usage, not the overall usage of the system right? I suppose if there was a problem drawing new water into the tank immediately, then you might run into trouble.... but if half the shower was run with pre-heated water, and the rest with fresh out of the ground water, that would result in more energy savings than not? Maybe I'm blowing smoke, just an idea, and I am a little tired. Good luck!

Water Heater

Reply #10 – October 27, 2009, 08:48:46 AM

oh,, i see what your saying now. I thought you meant dedicated lines to the showers.

I have ran into a problem though with the hose / tubing theory under the tin. As mentioned before, i had mid 70's inlet temps for a small amount of time.

if i increase the amount of tubing under the tin roof, the formula goes a little like this to calculate the gals of water in a tube....
pi*r2*ft*in / 277

so for 500ft of 3/4'' tubing, thats only 10gal. perhaps thats a good start. Water line tubing is really cheap by the spool, combine this with a storage tank near the Tempra24 and i might have something here.
add a recirc pump and that will consume energy also.
add a tank near the tempra is not exactly what i wanted to do. No realistic place to put a tank indoors that i would like to give space to.

I am going to have to wait for one of my coldest days to measure teh temp under the tin late at night. this will be my worse case test of temp drop. I dont want to add more plumbing or ideas until i find out exactly what temps i am dealing with first as to prevent rework.

the last cold time i measured was in march there abouts, i need to wait for one of those zero deg nights. Ill post more later on this.

I am contemplating an idea i think ,,,lol,, has not been thought of before. it occured to me a little while ago on the beech late at night while walking barefoot. the sand was still hot underneath just a couple inches down. sand holds heat,, might be an ingreedient i can use on what i am trying to do.

Water Heater

Reply #11 – October 27, 2009, 11:55:07 AM

Oh, maybe I misunderstood the amount of room under your roof. I was thinking you could tuck a tank or two right underneath the roof.

Sand...I can't see that going anywhere good!

Water Heater

Reply #12 – October 28, 2009, 12:05:38 AM

lol
no,, not sand on the roof man,:hick:

Water Heater

Reply #13 – December 12, 2009, 10:30:07 AM

Still going,
Power bill daily usage went from 5.22 bux per day to 4.01 per day.

Next up is to replace my Main breaker because i hear a buzz.

The Garden hose ting failed though,,,,right at 32deg also which was amazing. Thats ok though, i have a better heat exchanger in mind but its waiting till warmer weather.

Water Heater

Reply #14 – December 14, 2009, 10:35:13 PM

bear with me here, the flex hose to preheat as you suggested. old baseboard heater from a boiler system, or 3. The tough part is supporting the heat exchangers and the thermal transfer system you would need. Im thinking heat exchangers, submerged in water up in the peak of the roof. The heat exchangers are quite efficent being mostly copper and alum.
Dunno the exact layout in your home but I had considered a slightly smaller system submerged in a pond as a method of home cooling last summer when I was sweating my....