Boiler Not Heating Water


  #41  
Old 02-22-15, 04:27 PM
H
Member
Join Date: Dec 2013
Location: USA
Posts: 228
Likes: 0
Received 0 Likes on 0 Posts
And since they say in Table 3 that they recommend 1" pipe for a 20F rise, that would seem to imply that W-M thinks it's OK to run 1" pipe at 12 GPM... right?

You don't see anything wrong with that picture?
12 GPM is 4.34 ft/sec. for 1in pipe. Waste of pump HP?.
 
  #42  
Old 02-22-15, 05:24 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,427
Received 127 Likes on 119 Posts
HW,
Weil McLain CGa 3,4,5 have 1" tappings, 6,7 have 1 1/4" and 8 has 1 1/2".
I don't have any data to quantitatively say that. I did mean to say that the stress would fall within a acceptable range qualitatively, for systems that are not rapidly chilled.
Have you been listening to Prof. Irwin Corey.
 
  #43  
Old 02-22-15, 05:36 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,538
Likes: 0
Received 8 Likes on 6 Posts
Weil McLain CGa 3,4,5 have 1" tappings,
That's not so Spott.

Read post #34.

The boiler TAPPINGS are 1-1/4. Look at the notes below table 3. But they recommend reducing to 1" for the 3,4,5 section.

12 GPM is 4.34 ft/sec. for 1in pipe.
Not in the chart I use...

4 ft/s = 9.7 GPM

5 ft/s = 12.1 GPM

Not THAT far off... but a little.

IMHO, for 12 GPM they should spec 1-1/4"
 
  #44  
Old 02-22-15, 05:40 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,427
Received 127 Likes on 119 Posts
Trooper,
Suuply house .com.
They have the boilers there with all the specs.
WM generally has larger tappings and I was surprised myself. They do make other boilers and all have larger tappings but according to the specs the CGa's are as stated.
 
  #45  
Old 02-22-15, 05:46 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,538
Likes: 0
Received 8 Likes on 6 Posts
OK, whatever... what I posted is right from the W-M manual for the boiler.

It's right there in b&w under table 3. Re-read it and you'll see what I mean.

I'm SURE they don't make different castings for the different number of sections. They have a front, a back, and middle casting and they pull the number of them that they need. It would make ZERO economic sense for a manufacturer to do otherwise.
 
  #46  
Old 02-22-15, 05:58 PM
S
Member
Join Date: Oct 2013
Location: United States
Posts: 3,427
Received 127 Likes on 119 Posts
Trooper,
I found what you saw. It doesn't seem to make any sense. Right above the box with what you said is another box that gives you the boiler with the tapings. WM proof reading is out the window or I'm missing something.
Troop, if look at a closeup of his boiler it comes right out of the boiler 1". No reducing coupling on there. Same on the return.
Confusing.
 
  #47  
Old 02-22-15, 09:56 PM
H
Member
Join Date: Dec 2013
Location: USA
Posts: 228
Likes: 0
Received 0 Likes on 0 Posts
Trooper
Not in the chart I use...

4 ft/s = 9.7 GPM

5 ft/s = 12.1 GPM
Type M 1.055" Inside Dia. .035" Wall Thickness

4.0 ft/sec 10.91 gpm
4.4 ft/sec 12.0 gpm
5.0 ft/sec 13.64 gpm
5.13 ft/sec 14.0 gpm

STANDARD WEIGHT STEEL - SCH. 40 1.049" Inside Diameter
4.0 ft/sec 10.77 gpm
4.45 ft/sec 12.0 gpm
5.13 ft/sec 14.0 gpm

VELOCITY CHART & FRICTION OF WATER
Grundfos HVAC Technical Data Booklet.qxd 10/2/2002

Same for Taco pump selection
Selecting Circulators TD10
 
  #48  
Old 02-23-15, 07:30 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,538
Likes: 0
Received 8 Likes on 6 Posts
This from the 'Copper Tubing Handbook' is interesting, is it not?

Water Velocity Limitations—

To avoid excessive system noise and
the possibility of erosion-corrosion, the
designer should not exceed flow
velocities of 8 feet per second for cold
water and 5 feet per second in hot water
up to approximately 140F. In systems
where water temperatures routinely
exceed 140F, lower flow velocities
such as 2 to 3 feet per second should not
be exceeded
.
 

Last edited by NJT; 02-23-15 at 03:59 PM.
  #49  
Old 02-23-15, 01:08 PM
H
Member
Join Date: Dec 2013
Location: USA
Posts: 228
Likes: 0
Received 0 Likes on 0 Posts
Does ASHRAE say anyting about copper pipe?

Depends on how aggressive the chemistry of the water is but
tell that to the Copper-tube boiler manufactures, they use 7.0 ft/sec.
for the turbulence, all the turns are in brass or CI though.
 
  #50  
Old 02-23-15, 04:04 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,538
Likes: 0
Received 8 Likes on 6 Posts
Dunno, hain't looked... yet...

That previous quote came from here:

http://www.copper.org/publications/p...e_handbook.pdf
 
  #51  
Old 02-23-15, 04:48 PM
H
Member
Join Date: Dec 2013
Location: USA
Posts: 228
Likes: 0
Received 0 Likes on 0 Posts
Well I looked at it for something, it opened to Table 3c.
 
  #52  
Old 02-23-15, 04:55 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,538
Likes: 0
Received 8 Likes on 6 Posts
What you mean? Too cryptic for me...
 
  #53  
Old 02-23-15, 06:44 PM
H
Member
Join Date: Dec 2013
Location: USA
Posts: 228
Likes: 0
Received 0 Likes on 0 Posts
It's the pdf readers way of telling me that I was looking at that document -- It bookmarks the page on close. Why I was looking at it before you posted the link . . .
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: