My post about a water heater installation

[CHRISM]

I posted an answer - from a U.K. Registered Gas Engineers point of view - as to whether [from photos] a Gas Water Heater installation was `O.K.` ? - I believe that it is under the `Water Heater` section - I would be VERY INTERESTED in comments from U.S. Plumbers who are Qualified for Gas OR from Gas Engineers - relating to my `observations` on that Water Heater - specifically on the `Gas Vent` [we call it a `Flue`] - and I would be interested in what form[s] of `Testing` the Gas Vent would have to `PASS`??

I believe my post was entitled - Water Heater Installation - Legal ?? [or similar]

I would be very pleased to have comments regarding this - from Qualified persons - I want to find out `Definitive Procedures` regarding what can be a Lethal Situation - if installation AND Testing is not carried out correctly.

[Reedwalker]

I use a very simple test on smoke/flue vents. A simple match. When the appliance is firing light the match, then blow it out when its next to the damper. The smoke should be sucked up the flue. If it is not then you have a venting issue. In my experience its generally a squirrel or birds nest.

The lethality of CO is fierce. One of the symptoms is drowsiness. If you're already asleep.......

Is this what you were getting at ChrisM?

[CHRISM]

My post was asking Professional Plumbers and Gas Engineers - and `others` to view my Post about the Installation concerned - in conjunction with the Photos supplied by the `Original Questioner`/ `Poster.

Yes I was refering to `Spillage` of Combustion Products - AND the dangers of Incorrectly installed and Ventilated Appliances producing Carbon Monoxide.

The `Smoke Match` test that you refer to is just the `First Indication` that there MAY BE a `PULL` to the Gas Vent [Flue]

In the example [Photos] that I wrote a `lengthy` post about - the VITAL point is - that with ALL APPLIANCES running at the same time - the Gas Vent [Flue] is Safe and Capable to `evacuate` the products of combustion out of the building to a correct [High Level] Termination Point which is to `Code` - Regulations.
The Testing of the Appiances and the Gas Vent - MUST be carried out with ALL appliances that are connected to the Gas Vent [Flue] running at the same time.

I also made the point that in the U.K. - England - where I am based - the Horizontal Gas Vent [Flue] - wich is `obviously` `FANNED` - would HAVE TO include an Electrical `Interlock` which would PREVENT ANY of the Gas Appliances from being operated in the event of `Fan Failure`.
If Gas Appliances operated when the FAN was not working - the `Products of Combustion` COULD NOT be evacuated from the Building - they WOULD NOT evacuate along a Horizontal Gas Vent [Flue] - not even if there were a `slight rise`!!

Ventilation is also a VITAL area of a Gas Installation - and HAS TO be CALCULATED EXACTLY to the requirements of the Appliance and Site of the Appliance - OR the Combustion Process WILL be `compromised`.

Imagine this `Scenario`:

The FAN within the Gas Vent Installation FAILS.

The Gas Appliances `Fire Up` and the Combustion Process has started.

Because the FAN is not working - the `Products of Combustion` are NOT evacuated from the Building - and start `SPILLING` into the areas where the Appliaces are sited.

The `Products of Combustion` - mainly Carbon Dioxide and Water Vapour are NOW starting to `Vitiate` the AIR within the area of the Appliance sites -
ALTERING the `make up` of the AIR - removing OXYGEN from the AIR.

As OXYGEN is VITAL for Combustion - what then happens is `INCOMPLETE COMBUSTION` - THIS is a `process` which now produces CARBON MONOXIDE !! - THE KILLER !!

As you can see from my description - what is REQUIRED in this situation is MORE than an `initial investigation` with a `Smoke Match`

I am still hoping to get comments from Gas Engineers and Professional Plumbers who are `Expert` on GAS.

[Mr_David]

Sorry I'm not an engineer or an expert in this matter but it is a very interesting scenario. I'm not sure but I'm thinking a Horizontal fan assisted Gas Vent [Flue] for multiple appliances would not be allowed.
I haven't yet looked at the original post. Time permitting I'll try to go find it.

Fan assisted vents that I'm familiar with are designated for one appliance.

Have you found any good help with this. I am interested in what you found.

[Mr_David]

Found and read your comment

Originally Posted by Mr_David

Hi ChrisM,
I found your comment on post in question.
I doubt that it is a fan assisted vent.
This would most likely be a gravity vent.
You are probably right about the clearance from combustible material.
It's 1" for double walled vent pipe and 6" for single wall vent pipe.
From what I can see in the photos a horizontal vent such as that pictured maybe okay and acceptable according to the Uniform Plumbing Code.
The total horizontal run of a vent, plus the vent connector , shall not be greater than 75% of the vertical height of the vent.
The other vent from the another appliance is probably a forced air heating unit. The horizontal run would be considered the vent connector.
and shall have a continuous rise of not less than 1/4 inch per foot.

Floor furnaces with gravity vents are very common in some of the older homes here. I've seen and replaced horizontal vents that ran some 20 + feet before it went up the outside of the the house.

It seems that In the UK they require a lot of certifications. Here in San Diego the Contractor is responsible for proper installation. Unfortunately there is a lot of work done by untrained and unqualified people.
The local building Dept only inspects work when permits are pulled and a lot of work gets done with out permits.


And yes your posts are some what lengthy, but that's Okay. More info is better than not enough. I'm impressed by your thoroughness in a subject.
I apologize for my writing skills , Not one of my stronger skills.
Took me awhile just to compose this.

[CHRISM]

"Hi MrDavid" Thanks again for Your reply - You write WELL - I don`t know why YOU don`t think so ??

I can only reiterate that Horizontal `Natural Draft` Gas Vents [Flues] are NOT ALLOWED here in the U.K. - They are used in a `FANNED DRAFT` Installation - BUT then ONLY with an Electrical Interlock which would PREVENT the Gas Appliance from Operating IF the FAN were to `Fail`/ Not Operate.

To US - because our Gas Utilisation Organisations have Tested ALL types of Gas Installations that could be Installed - or even `Imagined`- We have Regulations which have been `Formed` from Rigourous Testing - THOUSANDS of Pages when viewed in Printed Form - In the case of THESE Horizontal Gas Vent [Flue] Installations - They are `Deemed` as `Completely Unacceptable`/ `IMMEDIATELY DANGEROUS` / `DEADLY` !!!

THIS is WHY I cannot believe that these `Installations` are `Perfectly Allowable` in the United States - WE are NOT `Wrong` about THIS - I personally have `Tested` `Mock Up` Installations where there is a section of the Vent [Flue] that is `Too Close` to the Horizontal Plane` - The Full Flow Test was `Unsuccessful` - NOT able to `Evacucuate Products of Combustion` - INSTALLATION CONDEMED !! - `IMMEDIATELY DANGEROUS`!!

To remain a `Legally Allowed` - Fully Qualified and Registered Gas Engineer here in the U.K. one has to take Assessment Exams every 5 Years - these Exams are VERY Detailed and include Testing on `Mock Up` Gas Installations - Some that are Perfectly `Sound`/ Correct - some that have `Problems` for the Gas Engineer to `Diagnose`/ Find.
The Testing of Gas Vents[Flues] is PART of these Exams /Assessments - AND Further `Scenarios`are often available to `View` / `Test` at the Examination & Training Establishments.

We HAVE TO keep `Up to Date` with changing Regulations & Practices on a VERY regular basis and we have Publications - Monthly - which are Dedicated to `Gas Utilisation`- one of these is sent to Gas Engineers as part of their Registration with the MANDATORY National `Governing Body that ALL Gas Engineers MUST be Registered with to `Operate / Work LEGALLY` - if NOT Registered it is ILLEGAL to Work as a Gas Engineer / Gas Installer.

That Installation was NOWHERE NEAR as Horizontal as `SMALL` a `Rise` of 1/4" of an Inch per Foot - it was more like a 20 Degree `Rise`!! - AND the Length was NOWHERE NEAR the 20 Feet that has been stated as `Not Unusual` on here !! - more like 6 Feet.

"Thanks again" for Your reply.


"Regards" CHRISM.

[LiQuId]

The match test is a good indicator that you have sufficiant draft..

Code...

Minimum effective vent hight 5 feet.

termination above a roof 2 feet ( chiminy 3 feet )

Can NOT terminate.
within 6 feet of a mechanical air supply to ANY building
-within 3 feet of any regulator/meter assemblly
-less than 1 foot above grade

..... these are the usual ones that come across.. that and window openings, which depend on the input rating for the appliances, feel free to ask away.

there are specific clearances required for Special venting systems as the products of combustion are acidic condensate that will erode pipe venting material, and damage appliances..

Feel free to ask Questions.

my qualifications are
-Red seal Plumber
-B class gasfitter.

And i agree that gasfitters should be required to re test to remain certified, but who is to pay for the re-certification ? I already paid. I think that if one can demonstrate that they have done qualified work in the field indicated that they should remain certified as to re-certify just by testing is to assume that because somebodys read the book, they can do the job... it takes a little of both IMO.

[CHRISM]

"Hello" LiQuId",

My comments here and in my Original Post about THIS Gas Appliance and its `Vent` / `Flue` are those of a U.K. Qualified & Licenced Gas Engineer - I don`t know if You have read my Original Post - which I think describes the Qualifications / Exams / Registration / Licencing of U.K. Gas Engineers ?

We would `Take One Look` at this Installation and `CONDEMN IT` - As `Not Installed Correctly` - regarding the `Vent` / `Flue` RISE [lack of it] - And the other `Defects` that I mentioned - It would be considered `IMMEDIATELY DANGEROUS`.

We would ONLY `Test` the `Vent`/ `Flue` to confirm that the Appliance is `IMMEDIATELY DANGEROUS` - The Appliance would either be `Disconnected` and the Gas Supply `Capped Off` - with `Permission` from the Owner / `Responsible Person` - OR - IF `Permission` was NOT forthcoming - We would contact the Gas Supplier - give details of the `Dangerous Installation` then THEY would go to the Address - Inspect what We had described and then `Disconnect & Cap Off` - OR - IF they could not `Gain Entry` they would `Disconnect & Cap Off` the Gas Meter - If located `Externally` - OR - If the Meter was located `Internally` [many in U.K. are] - The Gas Supplier has `Powers of Entry` which they WOULD USE to Enter the premises to `Disconnect & Cap Off` either the Appliance - Or possibly the Meter - depending on what they see on the Gas Installation.



The Smoke Match Test IS an `Indicator` that there is A `Draught` - IF used before the Gas Appliance is `Commissioned` - BUT the Smoke `Rising Up` the `Vent` / `Flue`/ Chimney does NOT Indicate that the `Vent` / `Flue`/ Chimney WILL allow ALL the VOLUME of the `Products of Combustion` to be Removed from the Appliance - when it is `Operating`.

A `Spillage Test` of the `Products of Combustion` has to be carried out when the Gas Appliance is FIRST `Commissioned` - OR `Serviced` - OR `Safety Checked` - IF more than one Appliance is connected to the `Vent` / `Flue` then these HAVE TO be `On` & `Firing` at the same time as the other Appliance - with BOTH being `Tested` for `Spillage` of the `Combustion Products`- the Appliances MUST be `Set` on MAXIMUM.

IF there were more than ONE Gas Appliance connected to a `Near Horizontal` Vent / Flue in the U.K. - The `Main Vent` would be `Fan Assisted` - There would be an `Electrical Interlock` between the Vent Fan Unit and ALL Appliances - IF the Vent Fan Unit `Failed` then the Electrical Interlock would PREVENT ANY of the Gas Appliances from `Working` - Meaning that there could NEVER be `Products of Combustion` entering the Vent / Flue that could NOT be Evacuated to Outside Air.

These `Spillage Tests` MUST be carried out by simulating the `WORST` possible conditions that may occur when the Appliance's are Operating - For example ALL Doors and Windows in the Appliance Locations are to be CLOSED - ANY Fans / Extractors/ Air Conditioners / Gas Fires / Gas Cookers etc. in the Area where the Gas Appliances are located are to be TURNED ON - to MAXIMUM Settings - An exception in the U.K. is a Cooker where there is a `Set` number of Burners that is regarded as the `Optimum setting` - Explaining this would be `Unnecessary` [for this point] - Any `Open Fires` should also be `Lit` and `Roaring` as they would be when used in Winter Weather - These Fires cause Large Volume Air Changes AND can cause a `Down Draught` within a Gas Appliance Vent / Flue Pipe - Or ANY Type of `Open` `Flue`/`Vent`. - This causes ALL of the `Products of Combustion` to `SPILL OUT` from the Gas Appliance !!


ANYTHING - that could `Influence` the `Evacuation` of the `Products of Combustion` should be `Operating`/ In Use - Creating the `Worst Possible Scenario` for the `Testing`.


A `Spillage Test` is to check that NONE of the `Products of Combustion` are `SPILLING OUT` from the Appliance - Into the Appliance Location - A Result of `Spillage` can be to `vitiate` the AIR within the Appliance Location / HOME - causing the Oxygen levels to `Fall` - this in turn causes the `Combustion Air` [Air for Combustion] to have less Oxygen than is `REQUIRED` for the `Combustion Process` - THIS causes `Incomplete Combustion` - which then results in the Production of CARBON MONOXIDE !! - At the same time the `Evacuation` of the `Products of Combustion` has `Slowed Down` EVEN MORE - Allowing MOST of the Carbon Monoxide to `SPILL` into the HOME / Appliance Location.

CARBON MONOXIDE is as We All know `The Silent Killer` !!

Some of these Appliances will probably NOT be encountered `ADJACENT`/ located in the same `Air Space` to Boilers / Furnaces / Warm Air Heaters etc. in the U.S. - As I believe that it is `Usual` for these to be Located in the `Basement Area` - BUT as I cannot `Rule Out` Appliances being located in the same area as `other` Appliances - I had to mention these regarding the `Spillage Testing`.

At the `Initial Inspection` stage - The Appliance [s] could either have a `Spillage Test` done to check that the `Products of Combustion` are being Evacuated from the Appliance / Building - Or a `Full Flow Flue [Vent] Test` could be performed FIRST - THIS is MY preference - The `Spillage Test` is a `MUST DO` when wanting to `Commission` the Appliance OR when `Testing` for `Safe Operation`.

I would use a Smoke Match to Check that there WAS a `Draft` PRIOR to carrying out a `Full Flow` Flue [U.K.] `Vent` Test - To establish that there was a chance that the `Vent` / `Flue`/ Chimney would `Evacuate` the `Products of Combustion` - Rather than light a Smoke Pellet first - only to find out that the Smoke Filled the area that the Appliance was located in.

I would then carry out a `Full Flow `Vent` / `Flue` Test` using an appropriately sized Smoke Pellet for the Vent / Flue Pipe / Appliance - this would be done without the Gas Appliance working - As an `Indication` that the `Vent` / `Flue` Pipe is `Sized` and `Routed` in such a way to allow the VOLUME of the `Products of Combustion` to be Evacuated from the Appliance / Building - Sometimes it is necessary to `Warm` the `Air Column`within the `Vent` / `Flue` Pipe to `Start` the `Updraft` - as would happen when the Gas Appliance `Fired Up`.

AFTER THIS I would then carry out a `Spillage Test` to Check if the `Products of Combustion` were being Evacuated from the Appliance / Building - Using a Smoke Match at the appropriate position on the Appliance -with the Appliance `Operating` on MAXIMUM and after approximately 5 - 10 Minutes of `Firing`.


From the Photos I would be fairly certain that this Appliance `Vent`/ `Flue` would NOT `Evacuate` the Products of Combustion correctly !


Unless I misunderstood You - You will see that the Use of a Smoke Match in the way previously mentioned is NOT a `SAFE` way to determine that the `Vent` Pipe is going to be `O.K.`


I HOPE THAT NO-ONE WILL DIE FROM THE RESULT OF THIS TYPE OF GAS APPLIANCE AND INCORRECTLY INSTALLED `VENTS` / `FLUES` !! - ALTHOUGH IT MUST BE HAPPENING - IF THIS INSTALLATION IS `PERFECTLY ALLOWABLE` - AND `CARRIED OUT` BY ANYONE WHO `KNOWS A BIT ABOUT GAS INSTALLATION` !


An Installation that I would `Class` as `IMMEDIATELY DANGEROUS` cannot be `O.K.` / `Fairly Standard` in the U.S. !


WHY would U.S. Gas Codes / Safety Regulations Allow `Dangerous Installations` ??


NO INSULT IS INTENDED HERE: It `Must Be` that We have had NO U.S. `Gas Engineers` on here - who are `Experts` in `Gas Utilisation` and U.S. Gas Codes - ??

I do NOT want this in order to `Validate` what I have been Writing on here - although it would be `Reassuring` regarding the `Safety` of the U.S. `Man in the Street` - I would like to KNOW that a `Professionally Installed` Gas Installation in the U.S. would be as `SAFE` as one installed here in the U.K. - ?? - Although that would STILL leave the Installations done by people that do NOT Know / Follow the correct Installation Procedures & Codes !


I am `Really Disappointed` that there have been no `Gas Engineers` on this Forum - I thought that as an `Associated Profession` [To Plumbing] that there MIGHT have been `Someone` who could `Verify` what I have described regarding THIS Gas Appliance and its `Vent` / `Flue` Pipe.


LiQuId - "Please" don`t take that comment as an `Insult` - I see that You ARE `Certified` to work on Gas - Are there `Limits` to what Gas Work that You can do with your present `Certification` ? - Are you able to Design & Calculate Gas Installations for `Various Appliances` ?


I have returned to this Subject` - after seeing that You `Posted` some comments on it - I have NOT written this Post as a `Put Down` - I feel so `Strongly` about `Gas Safety` that IF I were in the U.S. - I would have tried to contact the Questioner - to TRY and `Advise in the Strongest Terms` that He get a Gas Engineer to `Inspect and Test` this Gas Installation !

I HOPE that My Original Post gave Him some `Doubts` about the Installation - And that He MAY have had it `Checked` by a `Gas Engineer` OR his `Local Authority Building Engineering Department` - BUT - I Doubt that - As there were a couple of `Posts` that stated there was `Nothing Much Wrong` with it - Words to that Effect.


Again I cannot imagine that the U.S. `Gas Codes` can allow Installations such as this to `Exist` - What `seems` to be happening is that Gas Installations are NOT REGULATED enough - `Virtually ANYONE` can Install them and Installations are Not `Inspected` / `Tested` / `Certified` / `Passed` by Local Authority Gas Inspectors !


"Sorry Everyone" - About my `Rant` - But I really am `Vehement` regarding `Gas Safety`.


Again - the `Wall of Text` !


Regards,


CHRISM.

[Caduceus]

Very interesting read, guys. I looked at the initial post and would have to say that there are a number of issues that come up when looking at the photo. Quality of workmanship is the first to catch my eye. A 5" x 3" connection is legal if it terminates into a chimney, shaft or chase that exits to the open air and is designed for that specific use. Of course as homes are updated they are removed and replaced with double wall or better. It is a gravity vent and drafting as well as convection is a very reliable way to vent the harmful gases. The paneling is too close and I'm sure there are several more safety issues if an on site inspection were to be performed. Sealants as well as UL listed tapes are recommended or required.
Chris, don't use this as an example of an acceptable or normal piping arrangement. Like I said, poor workmanship. Power vented or appliances with air induction motors and vents can terminate horizontally outside of a home and must do so individually. They are all designed with safety sensors to shut down if any possible scenario presents itself. Specific guidelines are in place for materials, use of fittings, distances between termination outlets and air inlets. Most of these rules are not followed and the work is commonly done without inspection. I regularly recommend repipes of vents when installing hot water tanks because of sloppy work and if the situation is too dangerous and the homeowner doesn't want to pay for the additional work, I will not do the job.
I let you in on a little secret, just don't tell anybody.
Almost everything a plumber needs to know about proper venting of an appliance is in the installation manual.
You can probably download a manual from any manufacturer and see exactly how we should be doing here in the US. I love manuals...yes, it is sick, but I love em'.
Bradford White and AO Smith usually have some good info on venting their appliances.

[CHRISM]

"Hello Caduceus", Thanks for Your reply.

I KNOW that You were `Joking` when You said `Don`t tell anyone` BUT I look at Gas Installations Primarily from a Safety Point of view - NOT just to `criticise` the `Workmanship` - Incorrect Gas `Vents` / `Flues` can and DO Kill People.

The `Non - Evacuation` of `Products of Combustion` does Kill a number of People here in the `U.K. every Year - And We in the `Gas Installation` Sector are Highly Regulated / Registered & Licenced to carry out Gas Installations - ONLY Persons who are Registered and Licenced are Legally Allowed to Work with Gas - But of course there ARE `Illegal Workers`!

I know by looking at the Photos of the Original Post that this `Vent`/ `Flue` Pipe would NOT `Pass` a `Spillage Test` - Therefor it is VERY LIKELY to be `Spilling` Products of Combustion into the Dwelling - Hopefully NOT ENOUGH to `Vitiate` the Air in the Appliance Location - Lowering the Oxygen Level.

So it is `Likely` that the amount of `Products of Combustion` ARE `Spilling Out` - just - at present - NOT Enough to `Impair` the `Combustion Air` - Possibly because of `Adventitious Ventilation` [Draughts] - Because IF they DO Start to `Change` the Oxygen Level in the `Combustion Air` - THAT WILL BE THE START OF A `DEADLY PROCESS` !! - THE START OF `INCOMPLETE COMBUSTION`!! - THE START OF PRODUCTION OF CARBON MONOXIDE !!


Caduceus - THAT is WHY I am `Vociferous` on this matter - And WHY I have referred to this `Original Post` several times here on this Forum.


I realise that a `Plumbing Forum` cannot be `Expected` to produce Answers to My Specific Points about `Gas Installation` - As I AM a Qualified / Registered / Licenced Gas Engineer [One of my Qualifications] - But I thought that People would Either KNOW what they are writing about - OR - NOT Write about a subject as `Dangerous` to be `Wrong about` as GAS.


I am NOT referring to Your `Post` - I mention this to prevent the paragraph above from seeming to refer to You - I compliment You on your comments / knowledge.


IF I seem `Fanatical` about the subject of `Gas Safety` - I probably AM.


It is RARE that a mistake or `Bad Installation` in Plumbing Kills People.

Although I know of a recent Death that was caused by the Incorrect Installation of a Cold Water Storage Tank / Tank Base - When the Immersion Heater Thermostat failed on the Hot Water Cylinder [Tank] - The Hot Water Open Vent Pipe directed the Expanded Hot Water into the Cold Water Storage Tank - It `Cycled` back to the Hot Water Cylinder - Expanded back to the CWS Tank - Back Down to the Hot Water Cylinder etc. - This `Cycle` of almost Boiling Water caused the `Poly` Cold Water Tank to `SAG` - The Base for the Tank was NOT Large enough - It was almost the size of the Tank - This enabled the `Sagging` Tank to Completely `De-Shape` - Spilling the approximately 50 Gallons of almost Boiling Water onto & Down Through the Ceiling - Directly onto a Woman who was Sleeping in Bed below the Tank - She DIED from the `Massive Burns` !!

I believe that the `Plasterboard`/ `Drywall` Ceiling just `Disintegrated` from the Heat & Weight of the Water.

The almost Boiling Water - Although caused by a `Faulty Immersion Heater Thermostat` - would NOT have Killed Her IF the Tank Base had been constructed to the Regulation size - supplying the `Correct Support` to the Cold Water Storage Tank - The `Poly` Tanks here in the U.K. ARE Designed and Manufactured to be able to withstand `Many Hours` of this scenario - almost Boiling Water `Cycling` in & out of the Tank - BUT on this occasion the Tank was NOT correctly supported - and `Deflected` Sideways & Down` - Pouring Out the almost Boiling Water.


This Death caused the U.K. `Standards Authority` to set a Regulation that ALL Thermostats for Immersion Heaters MUST now have `High Limit` Thermostats - as well as the Water Temperature Thermostat - To prevent this type of `Dangerous Situation`.


So Caduceus - If I do seem to be VERY `Safety` Obsessed - ?? regarding `Gas Installations` [and other safety issues] - I cannot `Apologise` for being that way.


Regards,


CHRISM.