New furnace\boiler options for our home

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  #41  
Old 02-18-14, 06:39 PM
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If I didn't know better I'd swear I wrote that.
 
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  #42  
Old 07-04-14, 07:48 PM
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Well, I'm back resurrecting this thread I started last winter.

To be brief, I've removed both furnaces, their flue pipes, and the old humidifiers.

(The free-standing basement furnace return plenum is sitting on the floor under the hot air plenum.)

I've decided to install one furnace (probably either a Goodman 46000/32000 BTU or 69000/48000 BTU high efficiency), link up the basement and main-level hot-air plenums and use balancing dampers to regulate which of the two gets the most hot air.

There are two options for where to route the new furnace's two, 2" plastic pipes.

First, there is easy access to a joist space that would lead the pipes to an exit as follows:


The second, much-easier option is to go up to the roof through a finsihed tunnel on the main level that presently only carries the 8" flue (which used to carry flue gas from the two furnaces and the hot water heater, but now only the water heater).


Regardless of what choice I make about routing the Ipex, the flue from the water heater has to be increased from 3" to 4". I already know how to easily accomplish that within the present 8"-diameter flue.

I'm looking for a way to route the flue gas from the water heater AND the two Ipex pipes up that tunnel to the roof, sort of the way our neighbor does it with his two furnaces and a high effieciecy water heater. (How's that for a nice nest of pipes?)



I realize that it's verboten to route a hot metal pipe up next to the Ipex, but, again, I'm looking for a way that this can be done legally, because the pipes from the furnace will only about 4 feet from a plumb line dropped from the center of the 8" flue. Installing Ipex up through there would be an absolute snap.

I'd like to keep the John Wood water heater for as long as possible and replace it with another natural-draft unit when Woody inevitably fails.

I'm thinking that a double-wall, insulated 4" flue-pipe might do the trick. Route that up through the tunnel and the Ipex will still be a few inches away from it.

Alternatively, I believe that there may be adequate room between the present 8" flue and the corner of the finished tunnel as follows:


It may also be possible to put a double-wall insulated flue up the present 8" pipe. Then there's flue gas, a layer of insulation AND an air space between the hot gas and the Ipex.

What do you think? Any way to do what I want?

Thanks.
 

Last edited by Darwin's Child; 07-04-14 at 08:42 PM.
  #43  
Old 07-05-14, 01:47 PM
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FWIW, this morning I used an infrared thermometer (point it at the object, press the trigger and you get a temperature) to measure the temerature of the 3" flue out of the water heater. Max was 133 F. Does this sound possible?

I thought that the flue gas exhaust out of a water heater was much much hotter than that, but at least higher than 212 F.

If the exhaust temperature is indeed 133F, I don't see much of a reason why the Ipex pipes could not be placed in the same tunnel up to the roof.
 
  #44  
Old 07-05-14, 02:09 PM
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If you have room to do it, I'd suggest B-Vent up thru the existing 8" & the PVC along side the B-Vent. You could fabricate your own top.
 
  #45  
Old 07-05-14, 02:26 PM
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That temp sounds awfully low. Your hand should certainly tell you if the temp is actually that low.
 
  #46  
Old 07-05-14, 03:21 PM
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Hi, Grady. Long time, no hear. Do you mean placing the plastic pipe between the wall of the 4" B-vent and the wall of the 8" flue, or do you mean installing the plastic outside the 8" flue, as shown in my diagram?

I was able to touch the exhaust pipe and hold it there a couple of seconds. I think it felt cooler than hot water out of the tap at 140, which is way too hot for me. (Regardless, we're definitely not even in the same ballpark as the temperature of a flue on a wood stove.)

As the burning gas makes its way up the central tube that transfers heat to the water, it must cool considerably. I think of it as a burning-gas cooler rather than a water heater. After all, if the burning gas did not give up the vast majority of its heat before it exits the water heater, what would be the point?

These things must have been designed to heat water AND have an exhaust gas temperature that would be adequate for the gas to rise up and out of the flue without allowing its water vapor to condense. I don't know what that design temperature is, but I'd like to.

This being the case, the design as shown in my above diagram is going to be more than adequate to keep the plastic plenty cool. An insulated 4" vent would be way overkill, IMO. With the 4" flue going up its center, I doubt if the 8" flue is even going to be warm to the touch. The only real question is if the inspector going to approve the installation.

To lessen the possibility of rejection, before installing the furnace and its plastic pipe, right off the bat I can install the 4" vent up the middle of the 8" vent, run the water heater and measure the temperature of the portion of the 8" vent that presently pokes into the basement. If the temperature is much less than it is now, I can then proceed with the proposed design. After the installation, I can direct the inspector to touch the 8" vent as I did. If it's cool or only warm, what else can he do except approve the installation? (Famous last worlds.)

I'd be curious to see what others who have natural draft hot water heaters measure for an exhaust-gas temperature.
 
  #47  
Old 07-05-14, 05:42 PM
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I was thinking of running both the plastic & the B-Vent inside the 8" if there is room & if Hector the Inspector will allow it.
 
  #48  
Old 07-06-14, 08:55 AM
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Yes, in the end, everthing is dependent on the inspector's approval.

Speaking of approval and meeting code, what do you think of the exit layout of the first option I mentioned?

For that first option, I'm considering two exterior pipe configurations from the Goodman installation manual.

1.


2.


With the window, dryer vent and fresh air supply locations as laid out in that detailed photo, what do you think?

PS, I actually forgot to mention something.

Notice the fresh air intake on the side of the house. On the inside of the house, that insulated 5" round duct makes its way to the main-level intake plenum. I'm going to cut that duct just before it enters the plenum, install a 90-degree elbow toward the basement floor and install an insulated, flexible 5" duct that will lead to a point along the wall just behind the water heater, terminating about 18" above the floor in one of those "buckets" that allows air to exit, but not pour out all over the floor.

The reason I mention this is that I'm wondering if I could route the combustion-air intake plastic pipe right near that bucket and let the furnace suck in its combustion air right there, or, even more conveniently, install no combustion air pipe at all and just leave open that hole on the furnace cabinet. After all, this is what the water heater will continue to do, and this is what the two grossly-oversized (180,000 BTU combined input) Lennox furnaces have been doing for 36 years. At least with the new furnace, room air will not continue to be sucked up the 8" vent after the furnace turns off.

Then all I'd have to do is route ONE plastic pipe to the outside of the house for the furnace exhaust.

Again, what do you think?

Thanks.

BTW, as I was examining where the 8" vent penetrates the main-level floor, the water heater started up, so I took that opportunity to again measure the 3" vent's temperature. The angle at which the infrared thermometer is held is critical in obtaining the correct temperature. The highest I saw today was 172 F right on the top of a section of flue running mostly horizontal. I could still touch it for a second, but that was it. I also touched the 8" vent and it was much cooler. Highest reading there was 125 F.
 

Last edited by Darwin's Child; 07-06-14 at 11:17 AM.
  #49  
Old 07-06-14, 06:54 PM
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I just plain don't like one pipe vent systems. I use either a two pipe or concentric, usually a concentric, when sidewall venting. If I have a choice, & it's not crazy difficult, I like a vent going out the roof. I simply refuse to install a single pipe vent system. You might be able to use 3" B-Vent up thru the 8" for the water heater. Without measurements, water heater burner capacity, & a copy of the Canadian fuel gas code, I can't say for sure.
 
  #50  
Old 09-10-14, 09:21 AM
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Continuing this saga, there have been some developments. First, after looking at a single-furnace option for some time, we have decided to get two of the smallest Goodman two-stage furnaces. The basement unit will operate in low-stage only. The main-level furnace fan speed will be reduced from maximum -- how much, I'm not yet sure.

I have increased the 3" vent on the water heater to 4" and reduced the B-vent to 4" by running a 4" single wall pipe up the old B vent.




I fabricated the 60-degree storm collar myself, the template of which took me an hour to calculate and draw.

I have put together a full-scale model of one of our identical furnaces, which will supposedly be arriving next week. I did this in order to start determining the location and directions of the pieces of plastic vent and combustion-air pipe, particularly the ones on the basement furnace -- the one on the left as you face the furnaces from the front.

Here's a front view of the model in the left position. As you can see, I've marked on it the location of all significant openings.


As you can see, the gas drop for that furnace is going to be pretty close to the left side of the furnace, but I believe that I will be able to get a nipple in the tee that will go back to a 90-degree elbow to connect to the nipple coming out of the furnace. If necessary, I can install a flex line from the tee to the elbow.

The reason I'm writing this is that the plastic pipes that are going to be connected to the top of the left furnace are going to be a bit squeezed to get in between the gas header and the front of the main-level furnace's return air plenum, as shown in the side-view photo below:


I know that I can re-route the plastic pipe around just about any obstacle using elbows, but I'd like to minimize the number of elbows because we will be using two concentric vent terminations, as shown below.



As the number of elbows increases, the total length of the pipe shortens significantly --far more so than using a traditional, two-pipe termination.

Here's the joist space where the four pipes from two furnaces will enter:


From there it's a 14-foot straight shot to the outside wall:

As you can see, I'm going to have to chop about 4 or 5 inches of concrete off the top of the concrete outer wall that has been poured up into the space between the joists. I'm going to drill a row of holes in the concrete and then use hammer-only mode to break up the concrete above the holes. Then I can drill two 4" holes in the outer header, sheathing and siding trough which the vents will pass.

Again back to the reason I'm writing -- the gas header.

What I'd like to do is move either the entire natural gas header back away from, and parallel to, it's present position, or only the portion of it that is in front of the left furnace. That will allow me move the left furnace out a few inches so that its plastic pipe will have almost a straight shot at that joist space using very few 45 and/or 22.5-degree elbows.

I can see several ways to do this, with varying degrees of disassembly required for each.

I don't have a clue on code requirements with respect to changing directions on a gas line, so I hope you can give me some advice here.

The red arrow in the photo below

points to an invisible (in this photo) 90-degree elbow that is connected to the end of a 1" pipe/nipple that runs horizontally back to a 1" tee above the water heater. The white arrow points to the tee above the water heater. That pipe between the red and white arrows could be removed and replaced with one that is say 4 or 5 inches shorter and this would bring everything back toward the water heater that distance. This would allow the furnace on the left to be moved out just a few inches and then the plastic pipes could run much more directly toward the joist space that the pipes must enter.

Alternatively, I could remove everything after the elbow pointed out by the yellow arrow, rotate the elbow toward the water heater, install a 4 or 5 inch nipple, then another 90 degree elbow to direct the header back parallel to, but 4 or 5 inches back away from, its original direction.

A third option is to separate the pipe at the TEE pointed out by the black arrow, install a very short ("close") nipple, then a 90 pointing toward the water heater, then a 4 or 5" nipple, then another 90 that directs the header back parallel to, but 4 or 5 inches away from, its original position. Using this option also would move the left furnace's gas drop a couple of inches to the left of where it is now, giving a bit more space for whatever fittings or flex.

What do you think? How would you move that header a few inches away from the front of the left furnace (or both furnaces)?

Thanks very much for your advice.
 
  #51  
Old 09-10-14, 05:13 PM
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I would do whatever required the least amount of ells. I'm sure you have ample gas capacity but each ell is roughly equal to 10 feet of straight pipe when calculating total pipe length.
 
  #52  
Old 09-10-14, 07:57 PM
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Thanks, Grady.

By your criteria, replacing the horizontal line between the white and red arrows would be the best way to go. The number of elbows would remain exactly the same while the total length of pipe would lessen by 4 or 5 inches.

Right now I would estimate the total length of 1" pipe from the outdoor meter to the end of the left gas drop to be approximately 26 to 30 feet.
 
  #53  
Old 09-11-14, 10:49 AM
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PLENTY of gas for your equipment. You could almost make the gas go 'round & 'round & still not have to worry about pressure drop. That being the case, I'd do whatever is easiest to accomplish what you want to do.
 
  #54  
Old 09-11-14, 12:45 PM
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Thanks, Grady!

FYI, the total gas demand will be 32,000 BTU from the left furnace (permanently in low stage), 46,000 from the right (main-level) furance when its in high stage, 36,000 from the water heater and 38,400 from the Rinnai (when it's operating in its highest mode, which it never has). Therefore, if all of those appliances are running full tilt boogy at the same time (and if my math is correct) this gives a total demand for gas of 152,400 BTU/hr.
 
  #55  
Old 09-13-14, 11:34 AM
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If I were to replace the 1" elbow (pointed out by the yellow arrow in the previous photo) with a reducing TEE of say 1" x 1/2" x 1/2", can a 1/2" line be used to supply a 46,000 BTU/hr furnace?

Thanks.
 
  #56  
Old 09-13-14, 04:40 PM
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As long as the run is <30 feet of 1/2".
 
  #57  
Old 09-13-14, 05:42 PM
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Therefore, if all of those appliances are running full tilt boogy at the same time (and if my math is correct) this gives a total demand for gas of 152,400 BTU/hr.
You have to show a diagram of your piping layout from the gas meter to all appliances to figure gas rates... I tried to follow these posts but many were too long...

What is the farthest appliance from the gas meter in pipe distance?

Can you draw a gas diagram with all pipe sizes and lengths? And appliances on each branch and where they tee off?
 
  #58  
Old 09-14-14, 07:36 AM
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Just now read your responses, Grady's and lawrosa. Thanks.

First off, I should say that the 1/2" line from the TEE to the furnaces would be Gastite CSST.

I'll make a piping diagram and post it in the very near future, but, for now, note that both the Rinnai (38,000 BTU) and water heater (36,000 BTU) are BETWEEN the gas meter and the (old/)new furnaces and are fed by 1" x 1/2" reducing TEEs. The TEE to the rinnai is maybe 7 feet from the meter and the water heater maybe 15.

Also note in my first post that the combined gas demand of the two old furances was 186,000 BTU/hr. They were fed by a 1" gas header maybe 6 feet long in front of the two old furnaces with a 1" diameter drop to each furnace.

The total demand of the new furnaces will be 32,000 + 46,000 = 78,000 BTU/hr, which is only 42% of 186,000 BTU/hr.

The distance from a downward-pointing valve at the above-mentioned tee to the right furnace's gas valve will be no more than two feet. The distance from a leftward pointing valve to the left furnace's gas valve will be no more than 5 feet.
 

Last edited by Darwin's Child; 09-14-14 at 08:18 AM.
  #59  
Old 09-14-14, 12:02 PM
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Here is a diagram that shows pipe lengths, turns and loads:


The 1" line is even shorter than I thought.
 
  #60  
Old 09-15-14, 09:58 AM
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I have a correction to the above drawing. The 1/2" line to the Rinnai is 31 feet, not 36.

I measured the length of that line in the basement, right up to the outside wall. The end of that furnace that accepts the gas line is actually located short of the outside wall by about 5 feet.

Sorry about that error.

Also, I have already decided to use 3/4" Gastite from the isolation valves to the two new furnaces, so this should eliminate any further question about whether 1/2" CSST can adequately feed those furnaces.
 
  #61  
Old 09-15-14, 10:03 AM
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Your fine with whats there............
 
  #62  
Old 09-15-14, 02:01 PM
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Thanks, lawrosa.

On to another issue I'm having to deal with -- how to arrange the piping to TWO concentric vents in ONE joist space.

We'll have a pair of these concentric vents soon. Dimension X on the drawing will be 6-1/8".


Below is an actual size, end-view drawing I made of the joist space where they must fit. For the moment, just ignore everything on it except the ends of the joists and the empty space between them.


Now imagine what an end-view diagram of the concentric vents would look like with the vents oriented as they are (rotated as they are) in the first diagram of this post with two pipes connected to the vent port and combustion air port of the right vent.


Everything fits fine, but assuming that the concentric vents must slope back toward the furnaces a minimum 1/4" per foot, and also assuming that the two pipes of each vent must remain parallel to each other during that journey, there is going to be trouble a few feet back toward the furnace. Specifically, the combustion air pipe is going to run into whatever is attached to the bottom of the joists.

Here is what I came up with to solve the drop problem.

To maximize the amount of "drop" that is available to the combustion air pipes, the vents are rotated to about a 03:30 position.

But there is still a problem. A portion of the left vent's combustion air pipe will remain underneath the right vent's exhaust/vent pipe right to the end of the joist space and this will limit the amount of "drop" that is available to at least that exhaust pipe and quite possibly the other exhaust/vent as well, if the pipes of the left vent MUST remain perfectly parallel all the way (to prevent possible cracking the "Y" where the combustion air pipe meets the exhaust/vent, no fudging or bend allowed in both pipes of the same vent).

Here's what I came up with to solve all problems.


A side view of what I've done.

As you can see, I've installed two 45-degree elbows to "jog" the combustion air pipes over and up so that they are virtually in line and parallel with the exhaust/vent pipes. From that point onward, both vents can slope back toward the furnaces and all of the pipes will exit the joist space at the same height, maximizing the drop for the vent/exhaust pipes.

But............... and there always seems to be a "but".............in order to do the above, you can see that the center-lines of combustion air pipes are going to have to rise upward for a very short distance before they slope downward again with the exhaust pipes.

So, finally to my reason for making yet another long, laborious post. Do combustion air pipes have to slope back toward the furnaces in the same way that the exhaust/vent pipes do? In short, can I do what I propose above?

Thanks for the advice. (And I really do realize that the diagrams that have been photographed for this post do indeed look pornographic at first glance. That's what my wife said, anyway.)
 
  #63  
Old 09-17-14, 10:44 AM
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I discussed that last combustion-air pipe issue with the local code authority this morning. Essentially, they said to follow the manufacturers recommendations. Of course there is no mention of a need for the combustion-air pipe to slope back toward the furnaces in either the furnace or vent installation instructions, so I'm going to try to contact Goodman to get something in writing about whether the combustion air pipe must slope or not.

But, unfortnately, the code people just happened to ask why I needed an HVAC permit, in addition to the gas permit, if I was going to only install transitions between the new furnaces and the old hot-air plenums. I told them (by that time there were 3 of them hovering around) that had needed to remove the two vents from the old furnaces and, because of that, install a 4" liner up the old B-vent.

They asked me how I did the lining, so I told them in great detail. The told me that they would not approve the installation because I was supposed to use either 4" B-vent or some corrugated aluminum stuff that is specific for this porpose.

I told them that two different code people, there in that office, had told me that a min. 28 gauge single-wall galvanized pipe would be OK for that purpose, but they insisted that I, and their own colleagues, were wrong.

As you can imagine, I'm pretty upset by this turn of events.

So, are these people right? Am I going to have to undo what I've done and install either a 4" B-vent or corrugated aluminum liner?

I'm particularly interested in what any of you who might be Canadians have to say, but I'd welcome all comments on this. Would what I've described earlier to line our water heater vent be according to code in the US?
 
  #64  
Old 09-17-14, 11:10 AM
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I was supposed to use either 4" B-vent or some corrugated aluminum stuff that is specific for this porpose.
Would what I've described earlier to line our water heater vent be according to code in the US?

Yes double wall pipe or corrugated steel liner... And needs to be sized correctly to match the BTU's....

how to arrange the piping to TWO concentric vents in ONE joist space.
Why use the concentric fitting? You can pipe seperate as those fittings are $$$$$$$$$$$$..

Ill have to look at the instructions.
 
  #65  
Old 09-17-14, 12:05 PM
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Hi, lawrosa.

I just called the place I've been using for vent material and he says that the corrugated pipe in the vent-liner it is some kind of coated aluminum, not steel, buy maybe he's mistaken on this.

Before I retired, I was a laboratory technician in various power plants, including nuclear. In short, I know a bit about chemistry of metals and how they are affected by weak and stong acids. If the corrugated stuff is indeed coated aluminum, how suitable the stuff is for this purpose depends entirely on the lining material -- the coating-- over the aluminum. If it were uncoated aluminum, for this purpose, galvanized steel would be a far better material. After all, our galvanized-steel B-vent has lasted 36 years and is still intact, although it has a bit of surface corrosion near the top.

How much better than that can coated aluminum be? I doubt it's any better, and if the new world of tools, appliances, cars, etc., etc. is any indication of the evolution of quality, long life and reliability, probably a lot worse.

Here are the instructions for the vent:
http://www.alpinehomeair.com/related...%202.20121.pdf

Here are the instructions for the furnace(s):
Alpine Home Air Products: Contractor-grade furnaces, heaters, air conditioners and indoor-air quality products at wholesale prices.

I was essentially forced to go with concentric vents because I am restricted to using one joist space and I could not squeeze four pipes in there and maintain the separation requirements spelled out in the installation manual.

If you do a search on the Alpine site for "concentric vent", you will see that their vents are quite inexpensive (by my standard, anyway).
 
  #66  
Old 09-17-14, 12:28 PM
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I have never seen aluminum liners.. Maybe canada is different of the sales people dont have a clue.

Flexible Chimney Liners at affordable DIY prices

You would think any condensate would leach the coating off of aluminum eh!!!


Do combustion air pipes have to slope back toward the furnaces in the same way that the exhaust/vent pipes do? In short, can I do what I propose above?
Call the manufacturer and ask.. I guess as an intake it would not matter but there are instances in US instructions that may indicate your making somewhat of a air trap.
 
  #67  
Old 09-17-14, 12:49 PM
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Thanks, lawrosa.

The liner being required here is definitely not stanless steel, not for a natural draft water heater.

I was, however required to use a stainless-steel liner for our wood/coal stove (whose photo you can see in my original post that started this thread).

I agree with you about any coating's ability to remain adhered to aluminium for year after year of exposure to exhaust gas. (Just look at all those aluminum wheels on the road after a few years.)

Aluminum is going to expand and contract every single time the water heater runs and stops. Is that coating going to expand and contract at the same rate (as galvanized-steel's coating apparently does)? Is that coating perfectly applied, so that no raw aluminum is exposed to any gas or condensate? If it isn't, a hole will appear in a very short period of time. Most important, is that new liner going to last 36 years? Do I even have to ask?

I'll try to get something in writing from Goodman about the combustion air pipe slope/no slop. I think that will be easier said than done.
 
  #68  
Old 09-17-14, 02:57 PM
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I've installed aluminum flex liners. They are made by Z-Flex & Metal-Fab.

I doubt your B-vent is galvanized inside & out. All the B-vent I've seen is galvanized outside & aluminum inside. Metal-Fab, Inc. - Residential Products for residential and light commercial venting applications
 
  #69  
Old 09-17-14, 03:11 PM
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I've installed aluminum flex liners.
Interesting grady!!!

I guess it depends on the catorgory of the appliance...Here in NJ we follow NFGC NFPA 54...


UL listed aluminum chimney liner kit for use with Category I natural draft gas fired heating equipment and gas fireplaces.

For Use with Natural Draft Appliances.

Not intended for use with Category II, III, or IV gas burning appliances as defined by the National Fuel Gas Code, NFPA 54, or other appliances that result in condensation or corrosive acids on the liner of the chimney, or that create positive pressures in the chimney system.
 
  #70  
Old 09-17-14, 03:34 PM
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It's been years since I've installed one but used to do quite a few, especially for orphaned water heaters.
 
  #71  
Old 09-17-14, 03:56 PM
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Because Edmonton's winter weather is having a brief warm spell and I've got to act fast, I decided to buy and the kit that is being sold around here as an adequate substitute for the far more appropriate liner that I've already installed and will now have to remove.

When I called to order the thing, I asked if the 25-foot kit could fit in an SUV. The guy laughed and said it sure could. After I bought the thing, I realized why he laughed. The kit comes in a box that is 22" x 22" x 12"!



Here's a link to the kit's specifications:
Aluminum Liner Kit - Chimney Liner Kits - Gas, Aluminum - Novaflex

On the above site, I took particular note of the following (my underline):

"UL listed aluminum chimney liner kit for use with Category I natural draft gas fired heating equipment and gas fireplaces.
For Use with Natural Draft Appliances.
Not intended for use with Category II, III, or IV gas burning appliances as defined by the National Fuel Gas Code, NFPA 54, or other appliances that result in condensation or corrosive acids on the liner of the chimney.............."


After I install this "stuff" and the inspector approves the installation, I am going to have a very strong urge to go back to the 26 gauge galvanized steel system that I've got in there now, because this "system" is, IMEO, not well suited for this purpose. There is no way on God's green earth that that aluminum is going to last as long as the galvanized steel liner that's right now in the chimney as I'm typing.

Edmonton has very cold, very long winters. Therefore, the atmosphere in our well-ventilated attic (that sits above a main-level ceiling that is very well-insulated) gets very cold, and the portion of the vent that goes up through the attic must get very cold, too. This means that the periods of time when the pilot flame is on, but the heater is not heating water (which is a considerable length of time in our two-person household), the gas from that flame, as it passes up through the cold vent inside the attic, is almost certainly going to cool enough to condense any water that is in it and that water will almost certainly be acidic. The aluminum tube that is not supposed to be used as a vent for "other appliances that result in condensation or corrosive acids on the liner of the chimney" is almost certainly going to be experiencing just that.

To quote the title of one of my all-time favorite comedic movies, "It's a Mad, Mad, Mad, Mad World" out there, folks, and it isn't just unnecessary wars that I'm referring to.
 
  #72  
Old 09-17-14, 04:06 PM
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I'm going to ask an off-topic question here.

How do you quote previous people's comments and get them into those "balloons"?

Thanks.
 
  #73  
Old 09-17-14, 04:36 PM
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Your worrying too much... Put the liner in then drink a few brewskys...

CATEGORY I: Operates with a neutral or negative vent static pressure (measured at the outlet of the appliance). Heating appliance operates with a vent gas temperature that avoids excessive condensate production in the vent. Flue gas temperatures at the outlet of the appliance do not exceed 550 degrees F. The appliance conforms to the requirements of the National Fuel Gas Code, NFPA 54, and UL 441.



How do you quote previous people's comments and get them into those "balloons"?

Highlight the text to quote, and click the quote icon near the icon you click to post pics....
 
  #74  
Old 09-17-14, 04:40 PM
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I think you wil find the aluminum will hold up much better than will galvanized.
 
  #75  
Old 09-17-14, 05:32 PM
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"Highlight the text to quote, and click the quote icon near the icon you click to post pics.... "

I don't see any quote icon, nor do I see any icon to post pics.

Are you talking about the "manage attachments" button?

Thanks.

Grady, I'm 64. I hope that the liner lasts longer than I do
 
  #76  
Old 09-17-14, 06:19 PM
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I don't see any quote icon, nor do I see any icon to post pics.

Well LOL... How did you post your pics????
 
  #77  
Old 09-17-14, 06:39 PM
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I post my pics using Photobucket IMG links.

I'll take this opportunity to ask a much more specific question. Is the above 4" aluminum vent a proper size for a 36,000 BTU/hr natural draft water heater like ours? The vertical part of the vent line above the tee below the B-vent is approximately 20 feet high/long.

Thanks again.
 
  #78  
Old 09-17-14, 06:52 PM
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Is the above 4" aluminum vent a proper size for a 36,000 BTU/hr natural draft water heater like ours? The vertical part of the vent line above the tee below the B-vent is approximately 20 feet high/long.

I dont think so.. I believe ts 3" for a stand alone. ( I have to look at specs....)
 
  #79  
Old 09-17-14, 07:32 PM
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Look at post number 50 above.

I was told by the local code people that I had to replace a 3" vent that USED to connect the tripod on top of the water heater to the 3" fitting below the B-vent, with a 4" vent that would connect to a 4" tee that would connect to a 4" liner.

As you can see, I installed the 4" vent between the water heater and TEE and installed a 4" liner up the 7" ID (8" OD) B-vent the way post 50 shows.

From the very beginnig of this furnace project, I have been consulting with a licensed person who originally told me that a 4" galvanized-steel liner would be fine, but he has now told me that a corrugated aluminum liner would have to be FIVE inches! This is why I asked the latest question about the proper size for a liner.

This water heater vent issue is really starting to wear on me because I want to get whatever is the proper-sized vent installed tomorrow and, even at this point, I STILL don't know with certainty what the proper size vent is.

I really don't care what size I have to install. All I want is that it be acceptable for the inspector so sign off on. I'm beginning to feel like Don Quixote here, on his never-ending quest for his impossible dream.
 
  #80  
Old 09-17-14, 07:57 PM
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Listen ... Install whatever the inspector wants.... This is a US based website... Codes are different here is all I can say...

Talk to whoever you need to.... IMO your wasting your time posting your concerns here as it stands from what I know.....

Follow your local authority...period!
 
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