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    Fireplace specialist contractor

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  1. Unless you take samples and have them analyzed by an accredited lab, you're just guessing. Open flame combustion causes a lot of funny things to happen resulting in some interesting things being formed, both gaseous and solid. White residue/ powder is a common occurrence in and around open flames. Since there aren't supposed to be any solid or liquid fuel open flame heating devices in the home, we notice it with gas. Yes, you can get it with those gelled alcohol "fireplace"/ illuminaires and candles, too. What I typically see the most often in the lab reports I get from samples for Black Particulate Matter (you call it 'soot'), is a witches brew ranging from minerals such as titanium dioxide pigment from white paint to salts to fly ash, skin cells and dust. I wouldn't taste it but that's my preference. I'm not familiar with how acids are supposed to be in powder form as so often quoted but I am familiar with the residues from the reduction of a material by acids. FYI, the trace levels of sulfur in most NG and LPG should not be a consideration in this. The more common carbonic acid and at high temps. oxides of nitrogen would be possibilities including a pinch of nitric acid but it varies. I'd recommend a rigorous cleaning of the house including wiping down walls. However, as long as you're burning an open flame inside a structure don't be surprised at getting funky residues. Regarding CO, any signs of CO poisoning are very late, last minute before you die. If a CO alarm listed to UL 2034 alerts, get all occupants to a hospital because the algorithms in those alarms are set to coincide with 10% COHb, which is the medical definition of CO poisoning. Pungent odors can be caused by aldehydes but not CO itself, which has no odor. Signs of venting problems, such as the melted grommets on the top of a scorched water heater should be red flags but never wait for a person to complain of symptoms before suspecting CO poisoning. Those crummy alarms don't protect you from poisoning--they are death alarms. Get an unlisted CO monitor per floor and within 15 ft of each sleeping room. HTH
  2. An Oxygen Depletion Sensor or ODS safety pilot is nothing more than a finely tuned pilot designed to dropout at 18.5% ambient O2. Basically, the low O2 slows the flame speed sufficient to advance the pilot flame past the thermocouple to the point it drops out. ODS pilots are not field serviceable except cleaning them. You cannot replace just the thermocouple or adjust the bracket. You cannot ream out the orifice since it is an industrial ruby shot with a laser such that it resembles a spider web or snowflake. Should a plumber insert a drill bit to "clean it out", the ruby will shatter ruining the pilot. I call these "lung vented" appliances. While the CPSC does not have a documented death from CO generated by an ODS equipped appliance, the can and do emit significant pollutants including para and acetylaldehyes, nitrogen oxides and odors. Stats are not kept on how many people get sick from these things. FYI, the ANSI std. allows a max. of 200 ppm air free from ventfree appliances. Most of these units are grossly oversized for the space and construction. They must be kept meticulously clean and logs in the exact correct position per mfr.
  3. When VF logs are installed into a fireplace, the log mfr. typically requires the Fp meet the building code or NFPA 211 in the absence of a local bldg code. That would take care of the hearth extension. In addition, VF have a markedly increased clearance requirement over the header since that's where most of the heat is. A mantel that meets clearance for wood burning typically requires a 4" canopy or hood to push the heat well away from the facing. On a listed VF enclosure with VF logs, you'll need to refer to both the log mfrs. instructions as well as the enclosure listing. These logs project a lot of radiant heat onto the floor. The listing allows for a max. temp. rise of 117F above ambient, which then determines the level of floor and mantel protection or clearances. The position of any gas logset can have a major impact on the radiant heat to the hearth extension. Too far forwards can overheat the HX as well as the header. HTH
  4. Re-read my first post. I said the IRC still allows it. This, however, is a contradiction because the code also says all positive pressure venting must be listed. They can't make their minds up. These appliance mfrs. say its ok to use this pipe but the pipe mfrs. and other agencies say don't do it. That's all. Fernco says don't use their neoprene couplings for combustion venting but sells them to water heater mfrs. for use on power vented models included with the unit. Go figure.
  5. CAT IV listed venting would be the proper choice but in reality everyone gonna continue to use PVC until the codes or CPSC pull it.
  6. No statute Bill. As I said, the mfrs. state do NOT use it for combustion venting and IAPMO said don't do it. It is NOT listed to UL 1738 so technically its just some building material that a group of mfr.s decided to use without permission or a listing. It would be the same as using terra cotta sewer pipe with mortar joints and calling that ok. There is no test protocol to ensure polymeric venting is intact unlike DWV pipe. One problem is the pipe mfrs. specifically forbid the use of pressurized gas including air in testing their pipes, even at low pressures. Nobody wants to do a water test because it will leave a lot of water in the pipes that you have to figure out how to drain. I'm working on a protocol but it is not an easy nut to crack. Meanwhile, there are listed products available.
  7. B-vent listed to UL 441 for CAT I appliances only. No positive vent pressure. Natural draft only. Positive vent pressure appliances must vent into pipe listed for positive vent pressure, which is UL 1738 or PMI, which is where the illegal use of PVC comes from. PVC has never been approved for venting in the US by UL nor by IAPMO nor any mfrs. I'm aware of. Still allowed though by IRC for now.
  8. Yep note on boilers they only require a pressure relief valve and not a temperature/ pressure relief valve. ASME provides some flexibility as to location but on commercial applications the insurance underwriter and state boiler inspector will probably be very strict applying CSD-1 to relief valves. Also, they should be tested per mfr. and replaced very few years even if they appear to be working properly. Some mfrs. used to state about every 5-7 yrs but some of that has changed. The relief must match the max. rating on the rating plate. Very tall buildings may use 50 psi instead of the typical 30 psi for hydronics. 5 psi is typical for residential steam boilers. Note a 50 psi system would require a higher rated automatic fill valve and backflow preventer, too.
  9. The gage glass often froze first. Yes, the nipple was a vent. Circulator pumps didn't come about until 1923 and the widespread conversion to oil fired burners. Prior to that hydronic heating was gravity as noted by the large diameter pipes. If the upstairs rooms don't get enough heat have a technician drain the system and inspect for an orifice plate used to force more hot water into lower floor rads by gravity. Often those orifices weren't removed once converted over to forced circulation.
  10. A pro certified in CO/combustion analysis should test and correct as needed. The vent connector should rise straight up as far as possible while still making room for the 1/4" per LF slope up to the vent. The vent connector should be supported at the offset and every four feet. The vent should be inspected for obstruction (level II). There could be a a flow obstruction such as damaged inner liner or the use of TEK screws pushing in the inner liner instead of piercing it and pulling the two single walls together. If the B-vent joints have any screws, this is a common defect. A worst case depressurization test should be conducted. There is either a flow obstruction or a depressurization issue WRT the CAZ. This is just another reason to remove draft hoods--they work just as designed. They are the most dangerous item in a home. An NCI pro knows how to make the repair to a bullhead tee with double acting barometric damper and spill switch. Backdraft must always be investigated and corrected or somebody could wake up dead.
  11. If they rain rebar down the inside corners, rust jacking can cause this. With a listed metallic vent or chimney you won't see temperatures significant to cause thermal expansion or thermal shock. The listing allows for a maximum interior surface rise of 90?F from ambient.
  12. I would add to Bill's post: In South Dakota, I would suspect this is below the anticipated snow line. Definitely not an approved vent termination.
  13. The 3-2-10 rule dates back nationally to at least 1927. This chimney and the supporting pics show what appear to be soft fired bricks but definitely not SW or Severe Weather grade bricks intended for exterior use directly exposed. Note the salmon colored "Easy Bake" bricks, which are like sponges. Now note the hard Portland cement-based mortar. This mortar is waay harder than these chalky bricks which causes the destruction of the bricks from differential expansion along with freeze-thaw damage. Rebuild the chimney from the attic-up meeting the code height. The flashing could then be properly executed with the counterflashing let into the mortar joints held with mortar-no nails or caulk but floating above the step flashing. This type of brick used on modern houses is often the result of builders being suckered into reusing old salvaged bricks. Such bricks should be laid in lime mortar and are suitable for interior use only. Once the chimney has been properly rebuilt, I would recommend treatment with ChimneySaver water repellent. It is the only one I know of which meets the BIA recommendation for 100% vapor permeable or not at all. Typical "water repellents" rely on solids to seal the pores much like varnish. CSS changes the electrostatic charge to like poles with the water droplets while allowing water vapor to pass. It protects small cracks. Used by most chimney sweeps around the country successfully since '87. Junk like Thompson's will ruin masonry by trapping water inside. HTH.
  14. BTW, this appears to be a Majestic termination. They have been bought out numerous times over the last several years but now are owned by their old nemesis, Hearth & Home Technologies, Inc.
  15. Look inside the fireplace for the rating plate. If you cannot find a rating plate noting the mfr., model and serial number then treat it as an unlisted appliance which must be removed. Otherwise, defer to a qualified hearth pro. The stated clearances vary by unit to unit and not just mfr. to mfr. so you can NEVER assume or try to apply general measurements. One may be shorter and another may be longer--you have to read the listed installation instructions-period. I can tell you that functionally, if direct vent terminations don't have sufficient free circulation of air, they often operate sporadically. I've investigated many units that met the listed instructions for clearances but due to local effect of air currents and eddies, the thing just didn't run right or suffered outages, sooting, etc. HTH
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