Thread: black iron and galvanized pipes

hey all

did a job today. black iron and galvanized pipes connected all over basement. don't think that is allowed. there was not a service disconnect,but breaker box was ten feet away from furnace. 1925 house. no combustion air upper or lower.

city of denver said needed and zip permits pulled.

wrote all this up, what would you have done. of course owner came in at end and said OH KNOW ALL THAT IS GOOD.

said to him "check your hvac invoice, did contractor charge you for the permit he never pulled plus installation???

he roared off

later called me and said he was charged for permit

sometimes you feel like a hero in this job

but what about the disimmular metals

thanks

charlie

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Originally Posted by CHARLIE VAN FLEET

black iron and galvanized pipes

but what about the disimmular metals

Those are not dissimilar metals.

SO JERRY

is it ok to have so many sections different ? and what about the service disconnect a breaker?

charlie

Originally Posted by CHARLIE VAN FLEET

is it ok to have so many sections different ?

Nothing other than common sense says to use the same material ... guess they had certain lengths of pipe in their truck they needed to get rid of?

and what about the service disconnect a breaker?

Originally Posted by CHARLIE VAN FLEET

there was not a service disconnect,but breaker box was ten feet away from furnace.

I am presuming that you are referring to "there was not a service disconnect" for the furnace, right? And not that there was not a service disconnect for the electrical service, right?

If the breaker at the panel was within 50 feet, straight line sight, of the furnace, then it would be okay to use the breaker for that.

I've seen black iron used for plumbing by mistake. You get rust coming out of the faucets. All that rusting will lead to leaks, so it is wrong.
The big box stores sell black iron pipe in handy lengths, but AFAIK, it is intended for gas hookups, not plumbing.

Originally Posted by John Kogel

I've seen black iron used for plumbing by mistake. You get rust coming out of the faucets. All that rusting will lead to leaks, so it is wrong.
The big box stores sell black iron pipe in handy lengths, but AFAIK, it is intended for gas hookups, not plumbing.

John,

Being as that is being used for HVAC I am presuming gas, but you bring up a good point, it 'could be' plumbing serving hydronic heating systems??

did a job today. black iron and galvanized pipes connected all over basement. don't think that is allowed. there was not a service disconnect,but breaker box was ten feet away from furnace. 1925 house. no combustion air upper or lower.

Black iron and galvanized are both allowed here in MN (assuming gas piping). They are not dissimilar metals. The equipment disconnect isn't needed if the service panel is within eyesight of the furnace. Combustion air wasn't required here in MN until about 1984, so if the furnace is older than that it would not be required.

wrote all this up, what would you have done. of course owner came in at end and said OH KNOW ALL THAT IS GOOD.

said to him "check your hvac invoice, did contractor charge you for the permit he never pulled plus installation???

I wouldn't have discussed my findings with the seller.

Originally Posted by Ken Rowe

Black iron and galvanized are both allowed here in MN (assuming gas piping). They are not dissimilar metals. The equipment disconnect isn't needed if the service panel is within eyesight of the furnace. Combustion air wasn't required here in MN until about 1984, so if the furnace is older than that it would not be required.

I wouldn't have discussed my findings with the seller.

Just because both materials are covered with the same ASTM standard (A53) doesn't mean they are the same final product or will behave the same, they certainly don't have the same surface films, or necessarily by grade or that they were manufactured by the same process, (ERW, FbW, etc.), or that they will be the same on the galvanic scale, or that galvanic corrosion is the only factor to consider (other corrosion processes especially as the zinc coating is "sacraficed" to the acids in the environment and the now uncoated & exposed steel starts to corrode - i.e. rust, as we see in Charlie's picture). Independantly they might be permitted in some jurisdictions to be used indoors customer side for a residence (with exceptions to higher air/moisture environments, exposed in laundry areas (due to exposure to acidic environments & moisture), etc., but IMO the materials should not be mixed. Personally, am not a fan of using sch. 40 or 80 galv for customer side of the meter once indoors for residential NG piping, especially intermittantly.

Other factors influencing the rate and extent of corrosion potential also depend on electrical resistance of the joint between the metals (the pipe dope or tape sealant, which is normally applied to the threads further tends to increase the joint's electrical resistance further decreasing the corrosion potential), conductivity of the electrolyte, relative areas or masses of the anodic metal vs. the cathodic metal, the polarization of the anodic metal through the buildup of adherent surface films.

Sulfur/sour gas should not use galvy.

The zinc coating will sacrifice (more active or anodic) to the steel ;its coating deteriorated the galvanized steel pipe will corrode (rust), transfering its corrosion process to the lacquered black steel pipe, a.k.a. "black iron pipe". NG pipes are not oxygen free environments, nor are they "water free". NG in the pipeline is regularly mixed with "air" to adjust down when the mix is "too rich". Condensation in the "lines" is common. Exposed, the OD is subject to oxygen, moisture (especially moisture enriched indoor conditioned occupied spaces).

Black steel pipe (black iron pipe) has a lacquer coating IIRC from oil when the steel is hot. Similar to the "seasoning" coating one strives for/desires on "black iron" cookware (steel) [by heating cycles with oil or fat coatings develops a protective and naturally non-stick coating which appears black and improves over time/usage and functions until damaged by detergents, salts, soaking or cooking acid foods, scraping, or lack of use, etc. and then must be "re-seasoned"].

Steel "likes" slightly alkaline environment (negatively charged as it is) and will not corrode in pressence of fluid that is slightly alkaline unless oxygen is present or when dissimilar metals are connected with the carbon steel. Expose Steel to acid environment (positive charge) and water/oxygen and it will corrode much more rapidly.


Anodic end (most corrodible) to cathodic end (least corrodible)

Magnesium
Magnesium Alloys
Zinc
Galvanized Steel
Aluminum 5052H
Aluminum 3004
Aluminum 3003
Aluminum 1100
Aluminum 6053
Alcad Aluminum Alloys
Cadmium
Aluminum 2017
Aluminum 2024
Low-carbon Steel
Wrought Iron
Cast Iron
Ni-Resist
Type 410 Stainless Steel (active)
50Sn-50Pb Solder
Type 304 Stainless Steel (active)
Type 316 Stainless Steel (active)
Lead
Tin
Muntz Metal (C28000)
Manganese Bronze (C67500)
Naval Brass (C46400)
Nickel (active)
Inconel (active)
Cartridge Brass (C26000)
Admiralty Metal (C44300)
Aluminum Bronze (C61400)
Red Brass (C23000)
Copper (C11000)
Silicon Bronze (C65100)
Copper Nickel, 30% (C71500)
Nickel (passive)
Inconel (passive)
Monel
Type 304 Stainless Steel (passive)
Type 316 Stainless Steel (passive)
Brazing Filler Metals (silver-copper-zinc alloys)
Silver
Gold
Platinum
Cathodic End (least corrodible)


KR, I have NO idea why your recollection of when/if MN required combustion air for NG supplied HVAC equipment (much closer to SEA-LEVEL) would have any applicability to such equipment in Colorado. Especially since so much of the area is well above sea level (in fact much closer to 5,000 ft, than to MN's highest elevation and in many areas approaching near or above 7,000 ft. (where "thinner air" i.e. less available oxygen per cu. ft. of "space" makes availability of combustion air that much more important in Colorado), and since the history and choice of model code adoption and ammendments are specific to State and territory/region.

If you come across a situation/defect that presents what you believe to be potential danger it would be your duty to notify/warn the occupant of the condition/situation (ex. high CO readings; un-terminated, exposed "live" electrical conductor; etc.).

As far as the disconnect for the motor fan for the purpose of servicing - and location Colorado Springs area, it is my understanding that it would require two means of disconnect from the point of service. Since the interior panel is not a service even if conveniently located and/or able to be "locked out" and assuming the fan motor was on a dedicated circuit - it would still require a rated switch or motor disconnect within the control/view of the one servicing it (or a lock-out if not conveniently located in view/control of the one servicing it).

My understanding is only black pipe is to be used for N/G. galvanized is OK for N/G On the exterior but the Black pipe must be used on the interior.

If I see galvanized/Black pipe mix in the on the interior of a home I call it out.

Best

Ron

Originally Posted by H.G. Watson, Sr.

Just because both materials are covered with the same ASTM standard (A53) doesn't mean they are the same final product or will behave the same, they certainly don't have the same surface films, or necessarily by grade or that they were manufactured by the same process, (ERW, FbW, etc.), or that they will be the same on the galvanic scale, or that galvanic corrosion is the only factor to consider (other corrosion processes especially as the zinc coating is "sacraficed" to the acids in the environment and the now uncoated & exposed steel starts to corrode - i.e. rust, as we see in Charlie's picture). Independantly they might be permitted in some jurisdictions to be used indoors customer side for a residence (with exceptions to higher air/moisture environments, exposed in laundry areas (due to exposure to acidic environments & moisture), etc., but IMO the materials should not be mixed. Personally, am not a fan of using sch. 40 or 80 galv for customer side of the meter once indoors for residential NG piping, especially intermittantly.

Other factors influencing the rate and extent of corrosion potential also depend on electrical resistance of the joint between the metals (the pipe dope or tape sealant, which is normally applied to the threads further tends to increase the joint's electrical resistance further decreasing the corrosion potential), conductivity of the electrolyte, relative areas or masses of the anodic metal vs. the cathodic metal, the polarization of the anodic metal through the buildup of adherent surface films.

Sulfur/sour gas should not use galvy.

The zinc coating will sacrifice (more active or anodic) to the steel ;its coating deteriorated the galvanized steel pipe will corrode (rust), transfering its corrosion process to the lacquered black steel pipe, a.k.a. "black iron pipe". NG pipes are not oxygen free environments, nor are they "water free". NG in the pipeline is regularly mixed with "air" to adjust down when the mix is "too rich". Condensation in the "lines" is common. Exposed, the OD is subject to oxygen, moisture (especially moisture enriched indoor conditioned occupied spaces).

Black steel pipe (black iron pipe) has a lacquer coating IIRC from oil when the steel is hot. Similar to the "seasoning" coating one strives for/desires on "black iron" cookware (steel) [by heating cycles with oil or fat coatings develops a protective and naturally non-stick coating which appears black and improves over time/usage and functions until damaged by detergents, salts, soaking or cooking acid foods, scraping, or lack of use, etc. and then must be "re-seasoned"].

Steel "likes" slightly alkaline environment (negatively charged as it is) and will not corrode in pressence of fluid that is slightly alkaline unless oxygen is present or when dissimilar metals are connected with the carbon steel. Expose Steel to acid environment (positive charge) and water/oxygen and it will corrode much more rapidly.


Anodic end (most corrodible) to cathodic end (least corrodible)

Magnesium
Magnesium Alloys
Zinc
Galvanized Steel
Aluminum 5052H
Aluminum 3004
Aluminum 3003
Aluminum 1100
Aluminum 6053
Alcad Aluminum Alloys
Cadmium
Aluminum 2017
Aluminum 2024
Low-carbon Steel
Wrought Iron
Cast Iron
Ni-Resist
Type 410 Stainless Steel (active)
50Sn-50Pb Solder
Type 304 Stainless Steel (active)
Type 316 Stainless Steel (active)
Lead
Tin
Muntz Metal (C28000)
Manganese Bronze (C67500)
Naval Brass (C46400)
Nickel (active)
Inconel (active)
Cartridge Brass (C26000)
Admiralty Metal (C44300)
Aluminum Bronze (C61400)
Red Brass (C23000)
Copper (C11000)
Silicon Bronze (C65100)
Copper Nickel, 30% (C71500)
Nickel (passive)
Inconel (passive)
Monel
Type 304 Stainless Steel (passive)
Type 316 Stainless Steel (passive)
Brazing Filler Metals (silver-copper-zinc alloys)
Silver
Gold
Platinum
Cathodic End (least corrodible)

What is this, a filibuster? All that typing to agree with me that they are not dissimilar metals but in your opinion shouldn't be mixed?

Originally Posted by H.G. Watson, Sr.

KR, I have NO idea why your recollection of when/if MN required combustion air for NG supplied HVAC equipment (much closer to SEA-LEVEL) would have any applicability to such equipment in Colorado. Especially since so much of the area is well above sea level (in fact much closer to 5,000 ft, than to MN's highest elevation and in many areas approaching near or above 7,000 ft. (where "thinner air" i.e. less available oxygen per cu. ft. of "space" makes availability of combustion air that much more important in Colorado), and since the history and choice of model code adoption and ammendments are specific to State and territory/region.

You answered your own question. The reason I brought up the combustion air requirements in MN is because the code is state specific. I'm familiar with my state's requirements and the fact that it was not retroactive. The home is not required to meet current combustion air requirements if the furnace was installed prior to the code adoption. However, if the furnace is replaced it must then meet current requirements. Personally, I'll suggest adding it but it wouldn't make the summary of my report unless the furnace was newer than 1984.

Originally Posted by H.G. Watson, Sr.

If you come across a situation/defect that presents what you believe to be potential danger it would be your duty to notify/warn the occupant of the condition/situation (ex. high CO readings; un-terminated, exposed "live" electrical conductor; etc.).

If there is imminent danger I would tell the seller with my clients permission. High CO or gas leaks would qualify. Exposed "live" electrical conductors would not.

Originally Posted by H.G. Watson, Sr.

As far as the disconnect for the motor fan for the purpose of servicing - and location Colorado Springs area, it is my understanding that it would require two means of disconnect from the point of service. Since the interior panel is not a service even if conveniently located and/or able to be "locked out" and assuming the fan motor was on a dedicated circuit - it would still require a rated switch or motor disconnect within the control/view of the one servicing it (or a lock-out if not conveniently located in view/control of the one servicing it).

It sounds like you're talking about a blower door switch. We're talking about the equipment service switch for the furnace. Which can be the breaker in the service panel if it's within the line of sight of the furnace.

Quote:
Originally Posted by H.G. Watson, Sr.
If you come across a situation/defect that presents what you believe to be potential danger it would be your duty to notify/warn the occupant of the condition/situation (ex. high CO readings; un-terminated, exposed "live" electrical conductor; etc.).
If there is imminent danger I would tell the seller with my clients permission. High CO or gas leaks would qualify. Exposed "live" electrical conductors would not.


I find this discussion very interesting. First of all, with regards to determining the presence of an imminent danger, as defined by ANSI Standards, how do you determine this? Specifically, with regards to ambient CO levels, what method of sampling with what test instrumentation do you use? What is your action level based upon what standard? If you do find a "danger", what is your response?

Same for combustible gases.

Are you saying you don't have a problem with leaving a live exposed wire?

I'm just curious as you your response when someone enters after you and gets unjured or killed by a danger you had just identified but failed to warn or act upon.
Thx

Originally Posted by Bob Harper

I find this discussion very interesting. First of all, with regards to determining the presence of an imminent danger, as defined by ANSI Standards, how do you determine this? Specifically, with regards to ambient CO levels, what method of sampling with what test instrumentation do you use? What is your action level based upon what standard? If you do find a "danger", what is your response?

For CO I go by the EPA standard, tested inside flues, of 100 ppm. I'm less forgiving with ambient air, anything over 10 ppm. I use a Baccarach Monoxor III. I've got a form letter on my computer which I'll leave in the home if the owner isn't present.

Originally Posted by Bob Harper

Same for combustible gases.

I use a Tiff 8800A (I think). But, I have to be able to smell the gas leak also since the Tiff is very sensitive. I'll mark the leak with blue painter's tape and leave a form letter for the home owner.

Originally Posted by Bob Harper

Are you saying you don't have a problem with leaving a live exposed wire?

I'm just curious as you your response when someone enters after you and gets unjured or killed by a danger you had just identified but failed to warn or act upon.
Thx

With high CO or gas leaks the person living in the home can be injured or killed just by being present in the home. With exposed electrical wires, missing knock outs in a panel etc. a person has to perform an action to be injured or killed. In other words the person would need to touch the wires or stick their finger in the open knock out.

If I were to notify the homeowner on all hazards in the home I may as well just hand over every inspection report to the seller. Real estate laws, my inspection agreement and association standards of practice all protect me by saying the inspection report will only be provided to my client. Keep in mind I haven't "failed to warn or act upon" the hazards would be documented in my inspection report for my client. The current homeowner should already know of these hazards since they live there.

Originally Posted by Ken Rowe

What is this, a filibuster? All that typing to agree with me that they are not dissimilar metals but in your opinion shouldn't be mixed?

If you actually think that I agreed with your "they are not dissimilar metals" statement, you have some serious comprehension problems. I haven't had a need to review a version of the ASTM standard since prior to 01 but IIRC the standard outlines more than one "formula" for the steel pipes it covers. If you cannot grasp elementary level basics there is no point in expanding further .

Originally Posted by Ken Rowe

You answered your own question. The reason I brought up the combustion air requirements in MN is because the code is state specific. I'm familiar with my state's requirements and the fact that it was not retroactive. The home is not required to meet current combustion air requirements if the furnace was installed prior to the code adoption. However, if the furnace is replaced it must then meet current requirements. Personally, I'll suggest adding it but it wouldn't make the summary of my report unless the furnace was newer than 1984.

Again, you make no sense, nor does your MN specific justification. Don't care if the furnace was installed prior to 1984, not even if the home hasn't had any draft stopping/ insulation/window improvements or room area restrictions, If the fuel fired appliances are in an area which does not meet safe combustion air requirements (for example references by the manufacturer to ANSI standard, NFGC, etc.), sharing the space with other appliances, fans, etc.) it SHOULD be called out - period! If appears adequate and infiltration, etc. but you have called out insufficient insulation, excessive infiltration, poor quality windows, etc. IT SHOULD BE MENTIONED IN THE REPORT that such corrections as you have already pointed out would necessitate review of need for combustion air, and that changes in the requirements in MN have taken place since the furnace manufacture date.

Altitude adjustments (burner, etc.) and assuring sufficient oxygen supply (air) have been part of manufacturer's instructions, standards, and listing requirements for a long time. Again, your unlicensed status in MN, your unique "understanding" of what the plumbing, fuel gas, building, and mechanical codes in your area as demonstrated frequently here since your first appearance have been, "interesting" to say the least. Most especially your justification of unlicensed activity in Wisconsin, and your complete disregard for the former UPC based plumbing code and present codes in both MN and WI regarding clearance for a toilet.

Originally Posted by Ken Rowe

If there is imminent danger I would tell the seller with my clients permission. High CO or gas leaks would qualify. Exposed "live" electrical conductors would not.

Sad, that's all I can say.

Originally Posted by Ken Rowe

It sounds like you're talking about a blower door switch. We're talking about the equipment service switch for the furnace. Which can be the breaker in the service panel if it's within the line of sight of the furnace.

No, and considering the above, not surprising you cannot comprehend. Charlie said the panel present was NOT A SERVICE PANEL, that the SERVICE was not inside. As I read his contributions to this topic thread, the panel present did not have a main either. I was referring to the required second means of disconnect for the installed, not portable, heating/air handler appliance; i.e. the electrical supply to the Furnace appliance/equipment as a whole which includes the power to any/ALL fan motor(s) therein.

Many Residences in Denver, and certain suburbs (many of which ARE the electrical utility) do not have the "service" in or ON the residence. For example IIRC Longmont, CO (Boulder Co.) installs a combo Street light/electrical meter/SERVICE via lateral on the property at the easement, and a now customer owned (divested years back) feeder to a remote panel in or on the residence. GEC at this "ped" sent deep since the silica, intermittant but usual clay, salts, arid "Hardpan" surface soil is about as useless with a "driven" (you couldn't drive a rod if your life depended on it) 8' or 10' ground rod or MN "concrete encased electrode" as the Iraqi or Afganistan regions. Many of those older remote panels are SPLIT BUS as well.

Charlie said it was a 1925 residence with a breaker panel, he also indicated no service disconnect. JP covered possiblity of a panel MAIN and a dedicated circuit breaker acting as the second required disconnect, and if able to be locked out or in proximity and sight of the furnace: I covered the other, MORE LIKELY to the region possiblity - no service disconnect in or on the home, AND no remote panel MAIN and addressed THAT. Reasonable to infer the "breaker box" (upgrade possiblity from former fused panel - or might have been original "electrification!) might be DECADES OLD.

BTW here's another quick tip. The city limits of Denver have expanded over the years. County of Denver is now all within the city limits (annexation) of Denver. Didn't used to be that way. We have no way of knowing where in the city limits of Denver this 1925 structure is located, or when it was "electrified", OR connected to an electrical utility source.

Originally Posted by H.G. Watson, Sr.

If you actually think that I agreed with your "they are not dissimilar metals" statement, you have some serious comprehension problems. I haven't had a need to review a version of the ASTM standard since prior to 01 but IIRC the standard outlines more than one "formula" for the steel pipes it covers. If you cannot grasp elementary level basics there is no point in expanding further .

Maybe next time instead of copying and pasting 1000 words of text you'll just answer the question. For now, please cite the code that disallows galvanized gas pipe and black pipe from being joined together.

Originally Posted by H.G. Watson, Sr.

Again, you make no sense, nor does your MN specific justification. Don't care if the furnace was installed prior to 1984, not even if the home hasn't had any draft stopping/ insulation/window improvements or room area restrictions, If the fuel fired appliances are in an area which does not meet safe combustion air requirements (for example references by the manufacturer to ANSI standard, NFGC, etc.), sharing the space with other appliances, fans, etc.) it SHOULD be called out - period! If appears adequate and infiltration, etc. but you have called out insufficient insulation, excessive infiltration, poor quality windows, etc. IT SHOULD BE MENTIONED IN THE REPORT that such corrections as you have already pointed out would necessitate review of need for combustion air, and that changes in the requirements in MN have taken place since the furnace manufacture date.

Again, please cite the code or manufacturer's installation instructions that requires a combustion air source for the furnace installed prior to 1984. I previously stated that I would recommend the installation.

Originally Posted by H.G. Watson, Sr.

Altitude adjustments (burner, etc.) and assuring sufficient oxygen supply (air) have been part of manufacturer's instructions, standards, and listing requirements for a long time. Again, your unlicensed status in MN, your unique "understanding" of what the plumbing, fuel gas, building, and mechanical codes in your area as demonstrated frequently here since your first appearance have been, "interesting" to say the least. Most especially your justification of unlicensed activity in Wisconsin, and your complete disregard for the former UPC based plumbing code and present codes in both MN and WI regarding clearance for a toilet.

Sad, that's all I can say.

Interesting...how do I show a disregard to the UPC plumbing code or any code in MN or WI? I haven't done any plumbing work on any house (except my own) in the past 10 years. By the way, I've never inspected in WI, that's an assumption you made.

Originally Posted by H.G. Watson, Sr.;124155

No, and considering the above, not surprising you cannot comprehend. Charlie said the panel present was NOT A SERVICE PANEL, that the SERVICE was not inside. As I read his contributions to this topic thread, the panel present did not have a main either. I was referring to the required second means of disconnect for the installed, not portable, heating/air handler appliance; i.e. the electrical supply to the Furnace appliance/equipment as a whole which includes the power to any/ALL fan motor(s) therein.

Many Residences in Denver, and certain suburbs (many of which ARE the electrical utility) do not have the "service" in or ON the residence. For example IIRC Longmont, CO (Boulder Co.) installs a combo Street light/electrical meter/SERVICE via lateral on the property at the easement, and a now customer owned (divested years back) feeder to a remote panel in or on the residence. GEC at this "ped" sent deep since the silica, intermittant but usual clay, salts, arid "Hardpan" surface soil is about as useless with a "driven" (you couldn't drive a rod if your life depended on it) 8' or 10' ground rod or MN "concrete encased electrode" as the Iraqi or Afganistan regions. Many of those older remote panels are SPLIT BUS as well.

Charlie said it was a 1925 residence with a breaker panel, he also indicated no service disconnect. JP covered possiblity of a panel MAIN and a dedicated circuit breaker acting as the second required disconnect, and if able to be locked out or in proximity and sight of the furnace: I covered the other, MORE LIKELY to the region possiblity - no service disconnect in or on the home, AND no remote panel MAIN and addressed THAT. Reasonable to infer the "breaker box" (upgrade possiblity from former fused panel - or might have been original "electrification!) might be [U

DECADES[/u] OLD.

BTW here's another quick tip. The city limits of Denver have expanded over the years. County of Denver is now all within the city limits (annexation) of Denver. Didn't used to be that way. We have no way of knowing where in the city limits of Denver this 1925 structure is located, or when it was "electrified", OR connected to an electrical utility source.

No, Charlie said, "there was not a service disconnect,but breaker box was ten feet away from furnace". The context of the sentence shows "service disconnect" actually means appliance disconnect at the furnace, "But breaker box" means there was a breaker for the furnace in the electrical panel. I may be wrong, but I don't think so. Charlie will have to clarify his statement. Things aren't always black and white in this industry.

Ken wrote:"For CO I go by the EPA standard, tested inside flues, of 100 ppm. I'm less forgiving with ambient air, anything over 10 ppm. I use a Baccarach Monoxor III. I've got a form letter on my computer which I'll leave in the home if the owner isn't present.


Quote:
Originally Posted by Bob Harper
Same for combustible gases.
I use a Tiff 8800A (I think). But, I have to be able to smell the gas leak also since the Tiff is very sensitive. I'll mark the leak with blue painter's tape and leave a form letter for the home owner.
"

Ken, I think you confused the standards. The EPA does not publish stds. for flue gases but rather ambient room and outdoor air, which is 9ppm over 8 hrs TWA-PEL and 35ppm over 1 hr. TWA-PEL. The NCI recommended action level is 100ppm air free flue gas level. However, that is NOT a level that warrants immediate evacuation of the building. It does warrant investigation of the elevated levels by a qualified technician using a combustion analyzer. The NCI recommends the occupants exit voluntarily at 35ppm as read and immediate evacuation at 100ppm ambient as read (not TWA). If you instruct occupants to evacuate just because there is 100ppm in the flue with zero ppm ambient, you are fear mongering and being excessive.

The common evacuation level for combustible gases is 20% of the LEL. For NG, that is about 8,800ppm and 4,300 for LPG. Your TIFF 8800a cannot quantify gas levels. It only senses CH4 down to 500ppm, which is about 499ppm above the level most humans can detect with their noses (actually, the odorant gas added, which equates to this level of gas).

I qualified my post by referencing the ANSI Standard for alert words: caution, warning, and danger. Danger is used when there is an immediate threat to life or fire. An example is a significant leak of combustible gas or CO into an underventilated space. An ambient CO reading of 10ppm as read would probably warrant the use of the word "warning" and recommend followup with the appropriate agency or qualified technician. Similarly, getting a *hit* with a combustible gas sniffer would not warrant evacuation. Getting a reading of 20% of the LEL would warrant evacuation, shutting off then Tag Out/ Lock Out of the offending appliance.

The lack of proper MUA in an of itself should not trigger evacuation as that in an of itself cannot present a danger. However, the lack of MUA contributing to backdrafting with a resultant ambient CO level as read of 100ppm would trigger evacuation.......for the CO. The MUA issue should be reported to the client in terms of current codes and the hazard presented by not making adequate provision for it. Who cares what year MUA was first *required*. If it's lack presents a very real hazard to your client then it should be reported for repair regardless. If you find a pre-`1984 furnace that has inadequate MUA I would hope you are reporting two things: a) the furnace has outlived its useful life and even if it hasn't rotted through, is inefficient and should be replaced with modern higher efficiency equipment properly sized and installed and, b) provide MUA as needed. The furnace may have had adequate MUA when originally installed then later someone enclosed it into a mechanical closet and probably added a clothes dryer in that room, too.

If you find a loose hot wire sticking out where it is reasonable to believe someone could touch it and die and you fail to kill the power, flag it and notify the occupants and parties involved, then someone touches it, you could be found guilty of gross negligence and go to jail.

Copper doesn't rust so that's not the problem and generally speaking, only the super wealthy use copper drainage! You more than likely have old galvanized or cast iron which in either case and over time is a clogging nightmare! Your best option is plastic..........it's fairly cheap and will last pretty much forever so long as it is properly installed and water drains the way it should. Traps and flat lines where there's no heat in winter months with below 32F is going to be an issue. Some people will tell you septic lines won't freeze....................that's total BUBKUS! I've benn in the construction industry for over 35 years and have froze my tail feathers fixing them many times! SEWER LINES FREEZE!!