economizers

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Anne from Little Britan
Anne from Little Britan
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economizers

Post by csonics » Wed Nov 18, 2009 4:17 pm

Posted on behalf of farmerden:

armerden
Warming the Engine


Joined: 19 Apr 2008
Posts: 70
Location: Shawnigan Lake,B.C.
Posted: Wed Apr 15, 2009 7:14 pm Post subject: economizers
I'm thinking about adding an economizer to my boiler.What are the downsides? Am I going to have a noisy boiler feed pump ? Seems to me the positives outweigh the negatives. There's nothing worse than running neck and neck with another boat and having to add cold water to the boiler.Not that I'd ever consider racing steamboats but remember 2nd place is the first loser!!! Den
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87gn@tahoe
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Joined: 23 Feb 2009
Posts: 148
Location: South Lake Tahoe, CA
Posted: Thu Apr 16, 2009 11:29 pm Post subject:
Both mine and my father's boats have economizers... Both consist of a coil of copper tubing under the smoke hood. We both have shell & tube feedwater heaters as well.

There isn't really any disadvantages other than making things just a bit more complicated, and one more thing to potentially fail at the wong time..

You can avoid water hammer if you have a air chamber after your feedpump.

Make sure you have a way to completely bypass the economizer (i.e. a length of copper tubing, established valving and tubing, etc. ) just in case you sprig a leak in the economizer for whatever reason. And a simple way of testing for leaks; My father's boat had a leak in the shell & tube heater which caused us to be unable to make water in the boiler, but the hotwell was overflowing. We closed a valve between the heater and the boiler, then pressurized the heater with the hand feedpump.. We could hear the leak in the heater. We bypassed the heater, and problem solved

Not only is pre-heating the water good for economy (there will be a noticable increase in fuel economy for a given speed), but it can also prevent damage or undue strain on the boiler from pumping in cold water.

Remember, injectors heat up the water before entering the boiler also. BUT in my experience, injectors are inherently unreliable.

ALWAYS have at least 3 seperate means of getting water into your boiler (does not mean 3 hand feed pumps or 3 injectors), prefirrably with seperate plumbing from the water source to the device, and from the device into the boiler.

My ideal setup is an engine driven feedpump with economizer and/or shell and tube feed heater, a "reliable" (the term is relative) injector feeding directly into the boiler, and a hand feed pump feeding directly into the boiler but with provisions for feeding through the engine's feed pump system for troubleshooting purposes, amongst other things.


Sorry for the novel

wes
_________________
Wesley Harcourt
-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
-'64 Buick Riviera
-'65 Buick Special WAGON
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mcandrew1894
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Joined: 11 Oct 2007
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Posted: Thu May 07, 2009 4:03 am Post subject:
Wes,

We appear to have the same set ups!

Den,
Make sure the economizer stays drowned, meaning no check between it and the boiler, though a stop valve would be a good idea...per Wes's comments about isolation

Dave
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87gn@tahoe
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Joined: 23 Feb 2009
Posts: 148
Location: South Lake Tahoe, CA
Posted: Thu May 07, 2009 7:12 pm Post subject:
mcandrew1894 wrote:

Make sure the economizer stays drowned

yep

there's fine line between an economizer and a steam generator
_________________
Wesley Harcourt
-S.L. Wayward Belle (Mr. Grosjean was/is a genius.)
-S.L. George H. Sandin (Father's boat. Cut my teeth on that one.)
-'64 Buick Riviera
-'65 Buick Special WAGON
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farmerden
Warming the Engine


Joined: 19 Apr 2008
Posts: 70
Location: Shawnigan Lake,B.C.
Posted: Thu May 14, 2009 10:40 pm Post subject: economizers
Thanks you guys. As far as Injectors being unreliable,I had one It would lift,then the next time it wouldn't I'd pour cold water on it and it would work,on and on and on! The problem was the steam valve was leaking enough steam past to the injector and keeping it hot! So I talked to the sales rep for Red/White Valves [Also Toyo and whatever other companies they have acquired!] and he shipped me a new 3/8 shut off and the injector works like a dream-everytime! And yes I do have a boiler feed pump,injector,and hand pump [also perfect for hydro-testing the boiler every Spring!] Den
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mcandrew1894
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Joined: 11 Oct 2007
Posts: 149

Posted: Thu Jul 09, 2009 8:13 pm Post subject:
Just read an interesting fact from a US Navy Midshippmen's training course manual on water tube boilers dated 1950. Regarding economizers, they "usually" have check valves before and after the economizer to allow water to flow in only one direction. It stated to have a stop valve and check prior to the economizer inlet....

Dave
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barts
Lighting the Boiler


Joined: 02 May 2009
Posts: 32
Location: Menlo Park, CA
Posted: Mon Sep 28, 2009 9:39 pm Post subject:
mcandrew1894 wrote:
Just read an interesting fact from a US Navy Midshippmen's training course manual on water tube boilers dated 1950. Regarding economizers, they "usually" have check valves before and after the economizer to allow water to flow in only one direction. It stated to have a stop valve and check prior to the economizer inlet....

Dave


This is how our Otter is plumbed - a check before and after the economizer. With a float valve controlling the hotwell level, once the engine is running we're always pumping at least a little water through the economizer.

- Bart
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Bart Smaalders
S.L Otter
Menlo Park, CA
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