Another ? about storage for low mass boilers...Boilerpro

Boilerpro_3

I think I have a control and piping layout, but still looking for the type of tank I want to use. What I have in mind is to use an electric water heater and leave the elements in place. These elements would be used for back up heating should the boiler go down. However, I still would like to have 1 inch or larger tappings connection of the circulating lines. So far all I can find is the larger commercial (read more expensive) units that allow this configuration. Anybody out there found this configuration on a less expensive residential or light commercial model.

BTW, Bill Allen at Munch's Supply brought up this concern.... how well do the dip tubes hold up to the higher temp water often used with a boiler system. And are the tanks okay for this higher temp water? Most residential heaters are only designed for 160 F max, commercial okay to 180F.

Boilerpro

hr

my method

I use the top connection and the drain connection. A local supplier carries 3/4 MIP X 1" copper adapters that I screw into the connections. Yes there is a tiny pressure drop through that restricted reducer. Not nearly what you would have through a circuit setter, reduced port ball valve,Dahl mini ball valve, flow check, etc.

If you do use the element holes I can also buy a 1" MIP X 1-1/4" copper adapter for higher flow requirements.

Actually for hydronic applications you could remove the anode rod and free up another top connection. No need for anode protection in a closed loop system, boilers don't have them

Not sure about dip tube temperatures, I'll bet they handle at least 160F since BW CombiCors run that temperature with plastic dip tubes.

Actually soften and flare the end of a piece of 5/8" copper tube and build your own copper dip tube! I've done this many times, although you have a pressure drop through that tube also.

hot rod

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Floyd_5

Check these out..

Is this what your looking for???

Check out www.bockwaterheaters.com can't download their page so that I can post it, but they have larger openings.
Also they are probably more money....

Larry Weingarten

meddling here

Hello Hot Rod: A few meddlesome points I'd like to raise:) Taking an anode out of a tank just might be OK if there were nothing but steel in and around the tank. Otherwise protection from brass and copper fittings is lost... The warranty is another matter. Putting a copper dip tube in a copper tank is good. I suspect it will cause the steel in a glass lined tank to rust as long as the water has much conductivity. I have seen that anodes in tanks used just for radiant still corrode. Now State makes PEX dip tubes. How hot can PEX go? I've seen old Wirsbo test data done at 250 degrees and a dip tube will never see much pressure, (hopefully!). Have never tried flaring PEX to make a dip tube...

Kal Row

dont know if removing the anode is such

a good idea, In a regular boiler you have heavy cast jacket, the water heater on the other hand is thin and glass on steel – which constantly develops microscopic cracks, the anode fills in the steel at those points and protects the tank, in fact, if you change the anode, – every three years, – the tank, will never die, the ao-smith factory’s, own water heater, – is over 30 years old, they blow out the sediment every a couple of months, with a ball valve drain, and change the anode every 3 years – I got this info straight from them, – they even sell an anode with two bend points along it so that you can bend and straighten it out as you curve it into the tank, even if you only have about 18” clearance to the ceiling

Kal Row

if \"lifetime limited warranty\"

is music to your ears - check out

http://www.slantfin.com/spec-wh.html

The stainless steel storage tank resists rust and corrosion. Connections are specially reinforced to buffer the tank from stress when fittings are tightened. Heaters in residential use are covered by a lifetime limited warranty.

hr

Kal and Larry

corrosion can ONLY take place with the presence of O2. If the system is free of O2 via purgers or chemical O2 scavangers, corrosin cannot, and will not occur. At least that's what corrosion experts tell me You could drop a small steel nail into that tank of water, deplete it of O2 and keep it in that state, and the nail would not rust or corrode.

Used to be a test bench at a major radiant manufacture nearby that had a row of glass jars with a copper wire and a steel nail twisted together and dropped into a water and various brands of glyclos. Amazing the difference between the "bargin" glycols and the corrosion effect on the copper to steel interface.

This is exactly why the O2 scavanger is a critical component in glycol and hydronic treatments. And this is why yearly testing and boosters, if depleted, are recommended.

I still say the old copper and iron only systems lasted decades without corrosion problems. Wasn't until we went plastic, and rubber did we see corrosion problems. INCLUDINGD oxygen barrier products, a the DIN standard does not provide a complete stop of the ingress, it just slows it to a quote, unquote, managable level! although along these lines aluminum barriered tube makes more sense.

I suppose getting, and keeping the system in an O2 free state is easier said than done. Many places for potential O2 ingress in a closed pumped system, again a statement form the experts.

hot rod

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Kal Row

you are absalutly right about corrosion...

i was talking about the constantly occurring glass cracks - which will die from the outside in - talk to ao smith, they have more, i am fresh out of bs

all i know - is, that with T's and tapped-through bushings, you should have enough connections without using the anode port - we do that all the time with baseboard loops on a single port return steam boiler - i just use an 1-1/2 t, with 1x3/4 bushings that i tap all the way through so that i can screw a 3/4MxC adapters in on both sides and run the 3/4 pipe into the boiler as far as it will go less 1”,

with your water heater, you will need 1” T with 1x1/2 tapped-through bushings, and 1/2MxC adapter screwed into both ends – you can even use a 1x3/4 bushings – and screw a 3/4Mx1/2C on the inside, since you always want too limit the inside pipe to 1/2 so you don’t restrict the side outlet too much – and you will still have 3/4 out the top, of course use most of the bushing’s depth for the outside pipe – cause it has to seal, the inside pipe just has to hold on, a little thread leakage on the inside “ain-no-thang” - but do use thread-lock since expansion and contraction can turn it loose - (and boy, would i love an explanation for that one) – - I would try to screw both MxC adapters into the bushing in until they touch and solder them together –

this is a such a common use – I should ask nibco to make double ended C “through” adapters with one M thread - they do have 3/4 by 1 copper bushing that can adapt
a 1MxC adapter, or, maybe a 3/4 coupling would solder to the inside of a 1” CxFTG adapter which would intern be soldered to a 1xC adapter – hmmmm

ah – heck – just use the anode port - i kill me

Larry Weingarten

still meddling

Hello: There is a group, NACE,(National Association of Corrosion Engineers) "www.NACE.org" and although I'm not an engineer, I've been a member and learned from them for years. There are eight basic forms of corrosion and they don't nesessarily all need oxygen. What I believe is that galvanic corrosion (or two metal corrosion) works as long as there is a conductive electrolite, even without oxygen. I've been looking through the literature to find a place where this is plainly stated and haven't found it yet. So, I may be wrong. But becaust tanks are so thin compared to cast iron boilers, rusting can ruin them quickly. I've seen anodes work (corrode) even in supposedly oxygen free water. Actually I've never seen one that didn't. Seems it might be better to keep an anode in the tank. Perhaps a combo, anode-hot outlet type could be used if ports are hard to come by on a tank. Meddlesomely yours!

Kal Row

yeah - thats what the ao-smith engineer said..

something about voltaic action at the microscopic crack and failing from the outside in

Boilerpro_3

Am I lblind or

They don't offer electric. I am looking for a tank with electric elements so I have back up to the boiler.

Thanks Floyd

Boilerpro

Boilerpro_3

Looking for tanks with electric elements

for back up heating should a boiler go down.

Thanks Kal

Boilerpro

Boilerpro_3

Also

> corrosion can ONLY take place with the presence

> of O2. If the system is free of O2 via purgers

> or chemical O2 scavangers, corrosin cannot, and

> will not occur. At least that's what corrosion

> experts tell me You could drop a small steel

> nail into that tank of water, deplete it of O2

> and keep it in that state, and the nail would not

> rust or corrode.

>

> Used to be a test bench at a

> major radiant manufacture nearby that had a row

> of glass jars with a copper wire and a steel nail

> twisted together and dropped into a water and

> various brands of glyclos. Amazing the

> difference between the "bargin" glycols and the

> corrosion effect on the copper to steel

> interface.

>

> This is exactly why the O2

> scavanger is a critical component in glycol and

> hydronic treatments. And this is why yearly

> testing and boosters, if depleted, are

> recommended.

>

> I still say the old copper and

> iron only systems lasted decades without

> corrosion problems. Wasn't until we went

> plastic, and rubber did we see corrosion

> problems. INCLUDINGD oxygen barrier products, a

> the DIN standard does not provide a complete stop

> of the ingress, it just slows it to a quote,

> unquote, managable level! although along these

> lines aluminum barriered tube makes more

> sense.

>

> I suppose getting, and keeping the

> system in an O2 free state is easier said than

> done. Many places for potential O2 ingress in a

> closed pumped system, again a statement form the

> experts.

>

> hot rod

>

> _A

> HREF="http://www.heatinghelp.com/getListed.cfm?id=

> 144&Step=30"_To Learn More About This

> Professional, Click Here to Visit Their Ad in

> "Find A Professional"_/A_

Boilerpro_3

Also

How could copper tube boilers possibly survive for years if this kind of corrosion is a problem.You have copper tubes rolled right into cast iron headers. Right?

Boilerpro

Boilerpro_3

Thanks for the good perspective

Not much pressure drop to worry about for most residential systems. I suppose on larger systems you could just take two tanks and pipe them reverse return for balanced flow.

Boilpro

hr

Stainless

certainly is not impervious to corrosion, I've seen dozens of failed ss indirect tanks, over the years A narrow chloride acceptance level. I know we all test for that in our fill water, right!

But if stainless does seem better to you, the HTP SuperStor folks have stainless steel electric water heaters in their catalog from 6- 80 gallon capacity.

Seems to me water heaters are more apt to develop cracks in the lining due to the extreme thermal stress they see in DHW use. 140° tank suddenly seeing 35 degree incoming water, yikes. I think in a hydronic application this shock potential is greatly reduced as we are talking more like a 20° delta tee operating range.

In your quest for another tap you can use a side T&P connection with a brass tee IF! you use an extended shank T&P valve to assure the probe is in the tank.



For the past 3 years every one of my hydronic systems has gotton a Rhomar treatment which handles all these corrosion issues and many other nice fluid side benefits.

So bring on the steel, iron, brass, stinless, disimilar mix, even cracks in the glass lining !

hot rod

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DaveGateway

Hey Dave

Unless your flow is that critical, I'm with HR on using the 3/4 tappings. Increase immediately and cV should be pretty low. Brass nipples have a slightly larger ID than sweat adapters. Use the drain tapping and dip tube material becomes a non issue.
Tell Bill Allen I said hello. I went to grade school with him at St. Mary's in Mokena. Is he still at the New Lenox branch or did they open one out by you? Munch's started out in an ancient brick and timber warehouse in Joliet and then BOOM... branches all over. Good people to do business with.

Tom Goebig

hr

Look down the throat

of the connections on a Munchkin. That's a hydro formed 3/4 x 1-1/4 nipple as I recall. I'd like to get my hands on some of those as they have a nice smooth tapered transition over about 4" or so of length. Much friendlier to flow than a straight faced bushing or adapter, less flow turbulance potential. More like a funnel as opposed to a dike

Most all of the small HX condensing boilers have very small tappings. I think most started life, in another country, as flash type DHW units.

My 90K MZ has 3/4" tube coming of the connections.

Where it gets you in trouble are those instantanous water heaters where the entire HX is 3/8" tube coils. Now thats pressure drop defined. They can call the BTU output whatever they want but rarely can the back that up with GPM figures, in a hydronic setting

hot rod

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Floyd_5

Sorry, BP

I took from your oringinal post that the #1 thing of importance was the size of the holes, #2 the cost, and #3 electric heating if possible. Being that I don't think you'll find all three in one unit, that ain't a big commercial thingy, I figured that low cost and big tappings was the best you could get.

You ain't blind yet... :-)

I just misunderstood your priorities....

Floyd

Boilerpro_3

Yep , they're good folks

I work with the Aurora branch and Morris when I'm working in Ottawa area. Bill and Marv head up the commercial department for the whole company and work out of New Lenox. We have a good time working together.

It's amazing how small the world really is!

Boilerpro

Boilerpro_3

But definitely getting older

hope that means better!

Thanks again

Boilerpro

Kal Row

being that you already have the whole show

in place, with pumps and all - focuse on the best indirect and holding tank, and just pipe and valve in, an inline electric tankless unit heater

if you are installing it on the boiler side - you can get a small one - since you can run it for a longer time to bring the tank up to temp - as opposed to the output side, where you would have to deliver at least 1.5-3gpm at 120 for a shower - on the boiler side, you can get a 1gpm unit, and exchange time for size

besides, in the manifold world - you logicaly group your heat sources together so that you can stage or choose any one

on the other hand on the output side, you can take down your whole manifold show for service, and still have hot water - especially if the electric tankless bypasses the storage tank from the freash water inlet to the hot water outlet - so you can completely isolate and disconnect the storage tank

decisions, decisions, decisions.....

DaveGateway

Yeah...

And the older we get, the smaller it gets. Kinda cool really. In truth, Bill was a year ahead of me in that tiny school. I think my class graduated about fifty from eighth grade. Used to be rural....now it's a suburb. Sound familiar? At least urban sprawl is along way from Amboy.

Boilerpro_3

Urban sprawl is starting

We are starting to get that mini mall look north of town. Running about 12 new homes a year in town with three subdivisions on the edge of town. About a year ago the town annexed thousands of acres of land bringing a town from about 1 mile across out about another 4 miles. Amboy is the edge of Chicago growth now. About 30 miles east of us traffic is very heavy on the rural routes during rush hour.

Long range planning commission has been started with a professional planner hired. I hope we don't end up looking like most of the suburbs where the only way to get anywhere is by car....ugh.

Talked to Bill this morning and he says "HI"! Definitely remembers you and that you did mostly sheetmetal.

The incredibly shrinking world!

Boilerpro