# What's wrong with this schematic



## ILPlumber (Jun 17, 2008)

Had this on my desk. Thought I would toss it up here for discussion.


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## Wethead (Oct 13, 2008)

Its too small for me to read.....Do you have a bigger copy?


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## ILPlumber (Jun 17, 2008)

Sorry *******. It was a fax I recieved a while back. I never shrunk it down after the scan. I dunno how to make it bigger. 

I did a search in windows on my computer and found "magnifier". Works pretty well.


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## Wethead (Oct 13, 2008)

ILPlumber said:


> Sorry *******. It was a fax I recieved a while back. I never shrunk it down after the scan. I dunno how to make it bigger.
> 
> I did a search in windows on my computer and found "magnifier". Works pretty well.


OH yea, I could just download it and then just zoom 

Sorry, I forgot that , its Saturday


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## 22rifle (Jun 14, 2008)

If you have firefox you can hold down the control key while scrolling with your mouse wheel to blow it up bigger.


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## Wethead (Oct 13, 2008)

22rifle said:


> If you have firefox you can hold down the control key while scrolling with your mouse wheel to blow it up bigger.



Oh nice, I do have FF, going to try that now, and see if I can find whats wrong


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## 22rifle (Jun 14, 2008)

I am really confused by this one. I honestly don't understand what is going on.

You have the cold water coming in, and the hot water recirc line return coming in, but then you have a hot water going out to the fixtures and a separate hot water line for the recirc "supply".

Maybe I am just making a big fool out of myself by posting this. 

But unless what I just described is the cluster $%#& I think it is, then I guess I am just a confused dude on this.


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## Ron (Jun 12, 2008)

All water heaters need seismic strapping. Thats one thing wrong.


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## ILPlumber (Jun 17, 2008)

22rifle said:


> I am really confused by this one. I honestly don't understand what is going on.
> 
> You have the cold water coming in, and the hot water recirc line return coming in, but then you have a hot water going out to the fixtures and a separate hot water line for the recirc "supply".
> 
> ...


Is the line you think is the "recirc supply" the natural gas. I have multiple problems with this drawing. I'll let you guys discuss for a while until I post up mine. I've gotta go prep for my dad's suprise 60th birthday party. Nothing like shooting garbage bags full of oxy/acetylene with flaming arrows:yes: Yup, we're ********.


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## ILPlumber (Jun 17, 2008)

Ron The Plumber said:


> All water heaters need seismic strapping. Thats one thing wrong.


WH 3 shows typical seismic strapping. We do it around here too. We did have a 5.4 here in July.


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## A Good Plumber (Jun 18, 2008)

As I see it, these water heaters would work more efficiently if they were in series and not parallel piped.

But piped as they are,the 2" cold water supply needs a check valve.


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## Tankless (Jun 12, 2008)

Hmmm, The recirc line buggs me. THe way it is now heater #3 will be doing most of the reheating. It's not ballanced, the return should be closer to the 2" cold main to distribute the recirculated water. The main should be checked aswell.

2" cold water supply, 2 1/2" hot water distrobution piping..... But the gas looks good!!


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## muck (Oct 10, 2008)

Here the cold needs to be feed from a high above the water heaters. The inlet can be at the bottom but the supply must come down from a height higher than the water heater


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## Proud Plumber (Sep 15, 2008)

..........


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## JCsPlumbing (Jul 1, 2008)

Need a loop & vacuum break on bottom feeding. Thermostatic Valve. Feed the H/W return into the 2" feed with check valve. 

The H/W takeoff out of the top-side of the heater? What's up with that?

J.C.


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## pzmember (Sep 20, 2008)

i agree w/ tankless. the re-circ should tie in before the first tee on the cold feed, w/ a check on the main. and i havent seen an a.o. smith that gets its fuel feed on the top of the heater.


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## DUNBAR PLUMBING (Sep 11, 2008)

ILPlumber said:


> Is the line you think is the "recirc supply" the natural gas. I have multiple problems with this drawing. I'll let you guys discuss for a while until I post up mine. I've gotta go prep for my dad's suprise 60th birthday party. Nothing like shooting garbage bags full of oxy/acetylene with flaming arrows:yes: Yup, we're ********.


 

Get some video of that....I bet that's interesting.


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## ILPlumber (Jun 17, 2008)

Here's the problems I have with it.

1. No check on the cold feed.

2. Bottom feed WH needs a vacuum relief valve.

3.We can't have valving between the thermal exo tanks and the heater. Each heater would be required to have it's own with no valves between it and the heater.

4. Return line only goes back to the cold feed of the WH. So, if it;s pushing to the WH what is the only thing that can be pumped out to the loop? 140 degree water. The return also need piped to the hot feed of the tempering valve bypassing the WH. That way you let the tempering valve decide when it needs to add a littlle hot. 


^^^ That is a prolem I constantly follow behind other plumbers fixing. Tenants usually complain of scalding hot water at night. 

5. Pump away from the expansion tank(s). Recirc pump is immediately above it.


6.Hot outlet pipe needs a heat trap.


That's all I see off the top of my head. Feel free to add your opinion.


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## Plumberman (Jul 7, 2008)

ILPlumber said:


> Nothing like shooting garbage bags full of oxy/acetylene with flaming arrows:yes: Yup, we're ********.


Dude. thats an excellant idea. Solid,:yes: getting tired of shooting propane bottles with .22 magnums


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## ILPlumber (Jun 17, 2008)

We light the cutting torch to get the mixture just right. Snuff it out on a piece of steel leaving the valves open the same. Fill the trash bag and tie it off.

Put the trash bag on a stump. 

Shooting bale behind it. 

Shoot thru with a rag with lighter fluid on it. Don't get the rag too big.= heavy.

I go 40 yards. It is VERY loud. You feel the concussion in your chest when she goes.

Don't use your good arrows. They do disappear from time to time to be found with the bush-hog.:laughing:

I reiterate, It is LOUD. Louder than anything you ever heard. Some of the folks wear shooters muffs. I'd say it could break close windows.

You can make about anything disappear by filling it with oxy/acetylene.:yes:
It's magic I tell ya.:thumbsup:


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## Plumberman (Jul 7, 2008)

The concussion from propane bottles is loud too. Good idea:thumbup:


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## Redwood (Sep 8, 2008)

You can get a good bang out of snuffing a properly set cutting torch...

I had a 5' long piece of axle tube that I welded a cap on the end of...
I bored a 3/8" hole on the tube just above the cap...
I then put a piece of muffler pipe that had a perforated cap on the end that fit snug inside the axle tube and extended 3 1/2' inside and welded it in place....

Push a tight fitting potato down tube to the perforated cap then set the cutting torch to a good flame and snuff it...

Hold the torch in the 3/8 hole for a minute to fill the tube then take it away, light it and touch it to the hole...

Yep that was the best potato cannon I ever made...
I thing it was louder than my 300 magnum and I never did see the potato land... It left the area!:thumbup:


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## M5Plumb (Oct 2, 2008)

I don't see a check valve on the main supply line to all three W/H's...Am I missing something??


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## Hyper Piper (Nov 29, 2008)

I think the HWR should return to the cold header before it splits to supply the individual heaters, Also there should be a check valve installed in the cold header upstream of that connection. Should there be a heat trap loop into the cold supply as well? Depends on pipe configuration.
The method of tempering the 140 down to 120 is not clear to me in the posted pic. There may be issues with that.
This is a hip shot-Don't beat me up too badly!


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## LIVBMI (Sep 12, 2008)

There Is No Ball Valve Or Check Valve On The Supply Line.
I Never Seen Gas Connection On The Top Of A Heater And No Vent Pipe
If You Are Only Serving Fixtures What Is The Point Of The Mixing Valve.
Hard To Install The Expantion Tank At That Point
I Cant Read The Spec On The Heater But I Gess It Is Not Correct Either.


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## ILPlumber (Jun 17, 2008)

LIVBMI said:


> There Is No Ball Valve Or Check Valve On The Supply Line.
> I Never Seen Gas Connection On The Top Of A Heater And No Vent Pipe
> If You Are Only Serving Fixtures What Is The Point Of The Mixing Valve.
> Hard To Install The Expantion Tank At That Point
> I Cant Read The Spec On The Heater But I Gess It Is Not Correct Either.


 
High efficiency condensing WH's generally have the gas fed from the top. As well as the flame. Vent outlet is on the bottom. Not shown in the drawing prolly for clarity.

Thermostatic mixing valves are required on WH's serving the public here in IL. Run the tank at 140 and temper the loop down to 115. A WH thermostat is not a safe way to control temperature. Also, keeping the tank at 140 keeps bacteria from being at it's happy growing temperature.


Before long it will be required to circulate the loop @ 140 with a tempering valve at each fixture to keep the loop from "growing"


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## Tankless (Jun 12, 2008)

ILPlumber said:


> High efficiency condensing WH's generally have the gas fed from the top. As well as the flame. Vent outlet is on the bottom. Not shown in the drawing prolly for clarity.
> 
> Thermostatic mixing valves are required on WH's serving the public here in IL. Run the tank at 140 and temper the loop down to 115. A WH thermostat is not a safe way to control temperature. Also, keeping the tank at 140 keeps bacteria from being at it's happy growing temperature.
> 
> ...


 
Don't even say it...just get that thought right out of your head Mister....

Do you know what a temp rise to 140 on my tankless heaters does to the efficiency scale? ...right down the bowl with all the other crap.


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## plumber1a (Jan 3, 2009)

Did the Oxy/ acc thing a few times, once the static electricty from the bag set it off, threw me 20 feet into a wall, don't do that anymore. The heater diagrams don't indicate vent flews.


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## gladerunner (Jan 24, 2009)

no supply water


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