Will changing to 4" piping be worth it?

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gbreda

gbreda

Minister of Fire
Aug 3, 2009
1,255
Lakes Region, NH
My stove was installed by the dealer who used 3" ICC Excel pipe and a Harman wall thimble with OAK.

I have had to tape the seams due to a little leaking at startup. I have also had soot formed using softwood pellets on any feed rate above 3.5 (I know that the manual says to leave it at 4 and forget it). My ash is a darker color, almost black, and not grey.

I have read the following values are used to figure out EVL: 90 deg = 5, 1 ft horiz = 1, 1 ft vert = .5.

If the above is correct, ny EVL is 16.05 with the following: 2 90's, 65" rise and 41" horizontal.

I can do the changeover myself as I am now much more comfortable in the workings of a pellet stove. The question is this, is it worth the money to change? Am I losing more than the obvious listed above? I am leaning towards doing this over the summer.

I could always sell the 3" pipe to help the cost.

Any insight either way is appreciated.

Thanks

Geno
 

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usually, you should be going to 4" pipe with an EVL over 15' or so.......so, youre marginal there.....if you change over, you will no longer be able to use the wall thimble, since they are only 3", so you'll need a different thimble (haman doesnt make a 4" intake thimble), as well as new pipe......

I see you have a venturi end cap on that thing.....my first suggestion, before you go and buy new pipe, would be to yank that thing off of there and run for a bit without it.....see if it changes at all for you. If you do this, make sure you cover the pipe when you get done burning, so critters dont make a home in the pipe!

my 2 cents!
 
I will try removing the venturi end cap. I think that I have already tried removing the OAK pipe.
 
anyone else using the ICC pellet pipe that notices leaks. A rep came into our shop showing this pipe off. I liked the way it went together and seemed like it would not have a leak issue. How bout some feedback?
 
Most here that use it, swear by it. My problem may very well be that it is too small and should be 4". Even still, the leak would stop after the fire got going.

A friend of mine has 4" pipe on a direct vent set-up on an XXV with no issues at all. She had to go direct vent due to a garrison roofing set up.
 
I have the ICC Excel Pellet vent and haven't had any issues, but it is like anything else, someone not paying attention can damage it so it doesn't seal properly.
 
I used Excel Pellet pipe in my install and so far no problems or leaks. I like the pipe and I used 3 inch myself. Might have a couple of questions soon about how my stove is working shortly though.
 
I have the 4" excel and have not had any problems. I think that if you get smoke out of the joints the install might be wrong and the gaskets either got cut or were pulled out of there respective slots. Can there be that much presser that it can come out of the joints? I bought the excel because of the silicon gaskets.
 
It may not be necessary to use a 4" vent , but I would feel more comfortable with one... My installer used a 3" vent on my Castile insert, and says it's adequate, and it does work well, it has a good draft, however, Im thinking of changing it this summer and using 4" inch, it just seems to me that a slightly larger diameter will help the efficiency of the stove a little. Thats my 2 cents..
 
From your manual...

Venting
A combustion blower is used to extract the combustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as possible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the interior diameter should be increased from 3" to 4" because a larger pipe causes less flow resistance.
Click to expand...

I don't believe that the manual is talking about EVL... What I take from this paragraph is that total length of pipe should be less than 15 feet which you easily satisfy amd less than 48" horizontal which you also satisfy...

I agree that 4" pipe is better and I am glad that I have 4" but if I was in your situation I wouldn't spend the money to change it.

Perhaps in the off season you could take the stove outside and put a real short pipe on it to test for differences ?
 
cncpro said:
From your manual...

Venting
A combustion blower is used to extract the combustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as possible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the interior diameter should be increased from 3" to 4" because a larger pipe causes less flow resistance.
Click to expand...

I don't believe that the manual is talking about EVL... What I take from this paragraph is that total length of pipe should be less than 15 feet which you easily satisfy amd less than 48" horizontal which you also satisfy...

I agree that 4" pipe is better and I am glad that I have 4" but if I was in your situation I wouldn't spend the money to change it.

Perhaps in the off season you could take the stove outside and put a real short pipe on it to test for differences ?
Click to expand...

The manual was where I found the 15' mention and EVL is the question. Maybe why LW mentioned that my set up is marginal?

The manual does mention the use of elbows, so that should factor into the equation....and does. Unless you are direct venting straight out of a stove, all setups would have elbows if using rigid piping.
 
cncpro said:
From your manual...

Venting
A combustion blower is used to extract the combustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as possible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the interior diameter should be increased from 3" to 4" because a larger pipe causes less flow resistance.
Click to expand...

I don't believe that the manual is talking about EVL... What I take from this paragraph is that total length of pipe should be less than 15 feet which you easily satisfy amd less than 48" horizontal which you also satisfy...

I agree that 4" pipe is better and I am glad that I have 4" but if I was in your situation I wouldn't spend the money to change it.

Perhaps in the off season you could take the stove outside and put a real short pipe on it to test for differences ?
Click to expand...

I guess your manual is open to interpretation....and, the interpreters would be the inspector and installer. I DO believe the 15' is EVL, its kind of a standard in the industry, and when you are dealing with a big investment (the stove AND the home), the welfare of the family within, I would think to err on the side of caution......I said its marginal because it is close to the 15' EVL mathematics of your install.....ive seen many of these work like yours, which is why i said to simply take the end cap off, see if it makes a difference.....costs you nothing.
 
Lousyweather said:
cncpro said:
From your manual...

Venting
A combustion blower is used to extract the combustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as possible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the interior diameter should be increased from 3" to 4" because a larger pipe causes less flow resistance.
Click to expand...

I don't believe that the manual is talking about EVL... What I take from this paragraph is that total length of pipe should be less than 15 feet which you easily satisfy amd less than 48" horizontal which you also satisfy...

I agree that 4" pipe is better and I am glad that I have 4" but if I was in your situation I wouldn't spend the money to change it.

Perhaps in the off season you could take the stove outside and put a real short pipe on it to test for differences ?
Click to expand...

I guess your manual is open to interpretation....and, the interpreters would be the inspector and installer. I DO believe the 15' is EVL, its kind of a standard in the industry, and when you are dealing with a big investment (the stove AND the home), the welfare of the family within, I would think to err on the side of caution......I said its marginal because it is close to the 15' EVL mathematics of your install.....ive seen many of these work like yours, which is why i said to simply take the end cap off, see if it makes a difference.....costs you nothing.
Click to expand...

Hi LW, that what I thought on the EVL, thanks for clearing it up for me. I was home too late last night and will be taking the end cap off tonight. Should I be concerned about the end not having a screen (probably not) and also being less than 18" from the housing while I test?
 
Lousyweather said:
cncpro said:
From your manual...

Venting
A combustion blower is used to extract the combustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as possible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the interior diameter should be increased from 3" to 4" because a larger pipe causes less flow resistance.
Click to expand...

I don't believe that the manual is talking about EVL... What I take from this paragraph is that total length of pipe should be less than 15 feet which you easily satisfy amd less than 48" horizontal which you also satisfy...

I agree that 4" pipe is better and I am glad that I have 4" but if I was in your situation I wouldn't spend the money to change it.

Perhaps in the off season you could take the stove outside and put a real short pipe on it to test for differences ?
Click to expand...

I guess your manual is open to interpretation....and, the interpreters would be the inspector and installer. I DO believe the 15' is EVL, its kind of a standard in the industry, and when you are dealing with a big investment (the stove AND the home), the welfare of the family within, I would think to err on the side of caution......I said its marginal because it is close to the 15' EVL mathematics of your install.....ive seen many of these work like yours, which is why i said to simply take the end cap off, see if it makes a difference.....costs you nothing.
Click to expand...

You can verify what that manual is talking about by having your dealer call Harman and ask the direct question of them. I'll lay odds it is indeed talking about EVL since that is what venting is all about when you are using a forced draft.
 
I'm no installer and I have no training in this field but just reading the info in the manual leaves me wondering...

If they were talking about EVL why would they need to go into details like "minimal number of elbows" or "48 inches horizontal" ?

Also where EVL is discussed wouldn't there be some mention of altitude to go along with it ?

To me it looks like they tried to dumb it down for us average joes...

I agree that the best way to go about it would be to ask Harman directly.

I don't mean to be argumentative or beat a dead horse here so I'll leave it be now.
 
gbreda said:
Lousyweather said:
cncpro said:
From your manual...

Venting
A combustion blower is used to extract the combustion gases from the firebox. This causes a negative pressure in the firebox and a positive pressure in the venting system as shown in Fig. 7. The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Because of these facts we recommend using as few elbows as possible and 15 feet or less of vent pipe. The maximum horizontal run should not exceed 48". If more than 15 feet of pipe is needed, the interior diameter should be increased from 3" to 4" because a larger pipe causes less flow resistance.
Click to expand...

I don't believe that the manual is talking about EVL... What I take from this paragraph is that total length of pipe should be less than 15 feet which you easily satisfy amd less than 48" horizontal which you also satisfy...

I agree that 4" pipe is better and I am glad that I have 4" but if I was in your situation I wouldn't spend the money to change it.

Perhaps in the off season you could take the stove outside and put a real short pipe on it to test for differences ?
Click to expand...

I guess your manual is open to interpretation....and, the interpreters would be the inspector and installer. I DO believe the 15' is EVL, its kind of a standard in the industry, and when you are dealing with a big investment (the stove AND the home), the welfare of the family within, I would think to err on the side of caution......I said its marginal because it is close to the 15' EVL mathematics of your install.....ive seen many of these work like yours, which is why i said to simply take the end cap off, see if it makes a difference.....costs you nothing.
Click to expand...

Hi LW, that what I thought on the EVL, thanks for clearing it up for me. I was home too late last night and will be taking the end cap off tonight. Should I be concerned about the end not having a screen (probably not) and also being less than 18" from the housing while I test?
Click to expand...

I wouldnt worry about it not having a screen at this time of year, but, when you are done with the stove, make sure you cap it with something...a bag and elastic band, ball of tin foil, etc....birds and bee issue when the stove is off....Im NOT a fan of a screens, as they can plug....

As far as distance, you can always extend the pipe, but for testing, I'd leave it alone...I think you'll find you dont need to extend
 
gbreda said:
Most here that use it, swear by it. My problem may very well be that it is too small and should be 4". Even still, the leak would stop after the fire got going.

A friend of mine has 4" pipe on a direct vent set-up on an XXV with no issues at all. She had to go direct vent due to a garrison roofing set up.
Click to expand...

I have used the Excel pipe on two installs, and, yes would swear by it. I have no tape, nowhere, nohow. I used silicone only on the stove adapters.

I've used 3" with a Jamestown J-1000, in my Sun room hooked to a 7" wood stove chimney that provided almost automatic drafting.

I used 3" with my Englander's basement install, which has a 2.5 rise-to-run ratio, 2-90s, 1-45, a T and jet cap. I had so many problems with the Duravent PelletVent leaking that I switched to Excel and have had no leaks whatsoever. I almost thought I would need to go to 4" but the stove burns great the way it is.

From your pics, I can almost guarantee my basement install is way more complex than yours. So if you are having to tape the seams I think there is something wrong. Excel's 1/2" removable orange gaskets, laser welded seams virtually guarantee no leaks. Even Excel will tell you tape is not needed.

Are you sure the pipe is leaking? Did you mention your leaks to the installer (whom I'm sure use this product because they don't want to deal with leaks)? Have you pulled the pipe apart and inspected the seals and pipe (maybe a seal got pinched or dislodged since they are removeable)?

You paid top dollar for that pipe. You should not have any leaks.
 
Why do you need OAK on such a short pipe?, just a 3" plain exhaust would do fine, the room the stove is in with those unfinished windows looks like you'll have plenty of air to feed the stove.....talk about OVERKILL!! and a big waste of $$$$$
 
Sorry Pellet-King does not approve of an OAK, but I prefer to use one. Not a big added cost on this 16.05 EVL set up. Not huge length, but not short either.

Regarding the leak (which is not an issue at this time-I resolved that myself), it happened only on startup and went away after the fire got going. I took the whole system apart and checked the seals...they looked ok. The dealer in Chichester NH was going to take 3 weeks to come and check it out. Funny they took my money real quick. I did replace a leaking 90 deg and the person I spoke with on a Sunday at the shop gave the appearance of being very concerned and surprised that HE did not know about my issue....but did nothing to attempt to resolve it except give me a different 90 to install myself. He did not even offer me his name or position there if I needed further asisstance or quicker response. In restrospect, the shop there has decent feedeback here, but I have been dealing with Home and Hearth in Hampton since and they have been much more helpful with advice on a few issues.

I searched for info on Chichester and Hampton here before buying, but real life lesson learned. I have no actual experience with the service dept there and hopefully will not need to find out. They do not use servise for installs or leaks after install-found this out only after the install was done that they were not service techs. I tend to be loyal to a company that is helpful and knows what they are doing. I guided my girlfriend to Home and Hearth when she purchased a XXV in December.

Sorry for the rant. Not trying to start any negative dealer thing on this, just needed to vent a little.

Thank you LW and all for your input on this, it's much appreciated and helpful...I will keep it posted on any changes.
 
the best way to find leaks is to start the stove, turn the lights off, and use a flashlight
 
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