upgrading water heater system for more capacity

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frodo

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That's correct, Series is to be used when the 2 heaters are not the same. BECAUSE they cannot be in parallel.
But 2 WH's that ARE THE SAME
CAN BE EITHER WAY. Think about . Why would they have to be different.

I won't even try to get it through to you any longer. If you don't get it now, you better call the the people that wrote it.

You keep using a lot of words but are not saying anything different. I can't even make myself read that stuff you're writing. If you don't understand the basic concept, no amount of incorrect examples is going to change anything. You seem to keep repeating stuff from the article you read but obviously don't get the basic concept.

Do us both a favor and please call the manufacturer. Peace!
It says parallel is to be used when the 2 heaters are the same. Series is to be used when the 2 heaters are not the same. The language is clear to me.
one system [parallel] draws from both heaters
one system [series] draws from one heater, and uses the largest heater as a tempering tank.
You can hook up the water heaters any way you wish, and they will work, These are just recommendations for getting the best efficiency out of the system
Do not understand the personal attack when what I said is that you can hook them up any way you wish.

the Reason, that the in series piping diagram shows the 2 to be of different sizes is for efficiency

that is a undisputed fact confirmed by the Ruud co.
 

Diehard

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Do not understand the personal attack when what I said is that you can hook them up any way you wish.

the Reason, that the in series piping diagram shows the 2 to be of different sizes is for efficiency

that is a undisputed fact confirmed by the Ruud co.
Man...you're something else! Now you just changed your tune since you spoke with Ruud, as I suggested. You hate to be wrong.

No personal attack, just a little frustrating when you originally disputed the fact that they can be used in series if they are the same size and BTU.
 

frodo

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look at post 19, look at the date look at the date and time it was posted.
the last edit was saturday a hour before you posted ruud is not open on weekends
so no, i did not change my mind after talking to ruud. They confirmed my point

my position has not changed, the manufacture recommends that the 2 heaters be of different sizes
the reason is...and i pointed this out Saturday.. because of efficiency



It says parallel is to be used when the 2 heaters are the same. Series is to be used when the 2 heaters are not the same. The language is clear to me.
one system [parallel] draws from both heaters
one system [series] draws from one heater, and uses the largest heater as a tempering tank.
You can hook up the water heaters any way you wish, and they will work, These are just recommendations for getting the best efficiency out of the system



INSTALLATION - SERIES AND PARALLEL

The installation drawings in this bulletin are typical. Check local code requirements for vacuum breaker devices and cold-water inlet check valves. If you install a check valve in any of these systems, you must install a thermal expansion tank. There are two methods of manifold installation: series and parallel. Manifold means to pipe together with several apertures that make multiple connections. That is what manifolding is all about. Think about the intake and exhaust manifolds on a car. The carburetor sprays gasoline into the intake manifold (think of this as the cold water supply line). After the fuel is ignited by the spark plugs, the hot combustion gases are pushed out of the engine through the exhaust manifold (think of this as the hot water supply line). The intake and exhaust manifold on a car is an example of a parallel design.

Parallel Installation Parallel is what i recommended in the first answer I gave

Parallel installation uses heaters that are identical in both BTU input and storage capacity. Normally, parallel installation is used when there is a demand for large quantities of hot water over a short period of time, such as filling a large garden tub or back to back showers. Equipment being equal, two or more heaters connected in parallel will deliver more hot water than the same heaters connected in series. In a parallel configuration, the hot water ........................

Series Installation

Series installation uses heaters that are not identical in both BTU input and storage capacity. An example might be when an expansion or addition is made in an application that will require additional hot water. For example, you add a new bathroom to your home .The existing system will not handle the demand and a new water heater must be installed. The new heater is not identical to the existing heater. In this example, series installation may be appropriate. When installing water heaters in series, the heater with the largest input (BTU or KW) should be the first heater in the series, at the cold-water inlet side of the system. Series installation draws hot water from one tank at a time. As hot water is drawn, it is taken from the last heater in the series. For every gallon of hot water drawn.............
 

Diehard

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Initially you kept responding with that same quote you copied from Ruud.
"Series installation uses heaters that are not identical in both BTU input and storage capacity."

Perhaps you should have just acknowledged then that identical units could be used in series, as I was saying.

After I talked about using (2) 50 gal units(that's what he has), in my comment #16, you came back in your comment #17, again with, "Series installation uses heaters that are not identical in both BTU input and storage capacity."

After awhile I just quit reading your post as they seem to repeat themselves and go on and on about things we already know. For example, how series and parallel set-ups are piped, etc., etc. So yes, I didn't bother reading post #19, where you apparently, indirectly acknowledged what I was saying.

Would have been much simpler if you had just acknowledged what I was saying early on. But you didn't. So I had no choice but to conclude that you were strictly going by what you were reading and not completely understanding it.

I mean we were trying to help someone with a situation where he had (2) water heaters of the same size but remotely located. An arrangement that would lend itself to a series arrangement. When you go off in tangents it gets a bit confusing for my little brain.
 

bikeboy

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OK; is it possible to just bring a 1/2" line from WH circuit#2 hot side , and T it into whirlpool tub spiket branch to add hot water to feed tub with WH#1 ? could I just T the two circuits, install a mini tank, or mixer to combine them @ tub's@hot side ?

HR...
 
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bikeboy

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OK; It's been a while. I haven't started on this project yet, because I know having already two 50 gal. HW htrs, there has to be a way to simply combine them by balancing the flow from both WH's. If a 3/4 HW line brought from WH2 to WH1 and either combine them using a pressure balancing valve, or fabricate a bypass loop using check valves, 2 flow meters and ball valves , and lowering the flow of the closer WH. to match the given lower flow from WH2; it be like a set and forget. Would it work, and be able to equally dray from both water heaters ?

Please reply,
TNX.
HR...
 
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