I believe Tom or Mark can answer this question for me. I have read that after April 2015 gas hot water tanks over 55 gallons will have to have a PVC flue instead of metal flue pipe. Do you know if there is any changes that effect 50 gallon or less hot water tanks in regards to flue pipe, since this will affect many single floor home or condo owners mostly that live in slab houses and if they would have to change to PVC, it would mean running a new PVC flue through the roof next to their, in most cases next to their metal chimney. I know supply houses in this area are buying up all the tanks with metal flues now that they can, so they will have them after the April 2015 change.
Thanks for any information you can give me. I realize most condos and single family homes use tanks that are smaller than 55 gallons, but I am interested in a instants where a bigger tank might have to be used.

Hi Puffmugs

I have not heard of this change, but that could be due to the state I live in... Massachusetts has its own state code, but it is one of the STRICTEST in the country, so would be surprised to hear that there is change happening across the country without us (or CA, NY) knowing about it!

In my area, we are now required to install a hard-wired CO detector with all new water heater installations, but I simply don't see how any state could require a homeowner to change out their entire venting system... doesn't make sense to me at all!

Further, to reduce the combustion gasses to a temperature that would work safely with PVC would require a fan-assisted setup and I don't see that happening as a requirement for small or large water heaters any time too soon!

I would suggest that you call your local plumbing inspector and ask him about this. I would be very interested to know what he has to say and what plumbing code you fall under.

Have a good day!

Mark

Thanks Mark, according to the plumbing inspector in this area this is a national government change to go into effect in April 2015 that all 55 gallon hot water tanks or larger have PVC power vents as part of a energy saving policy on a national level by the government to save energy. I fall under the Ohio plumbing code, but this is a national change. I did Google this also, and found this change to be correct. That is all the information I could come up with, if you have the time maybe you can find another aspect to this, as it seems this will cause many hardships on many people. Due to this change I understand that Bradford White has doubled the size of their hot water tank division to comply with this.

In California, some of the upgrades have been already implemented: larger Thermal Value Insulation, Pilot-less ignition and all Tankless hot waters heater are since Jan. 2014 condensing ones. Enclosing link from Bradford White Corp. explaining the new EF requirements...

http://www.bradfordwhite.com/sites/d...15-article.pdf

PVC pipe, and its use as a vent system for gas fired appliances, is under review, and, is destined to be banned for such use. While several boiler and water heater manufacturers specify PVC as a flue gas vent connector, NO PVC pipe manufacturer tests their pipe for use as a vent connector, and, NO pipe manufacturer approves it for venting gas appliances...

Mike 45, can you tell us where you got this info? We have been using PVC pipe to vent furnaces rated at 90 or higher for quite some time, per manufacturer instructions. http://www.rinnai.us/blog/entry/tank...r-venting-tips

Mike45plus: The latest tankless hot water heaters, as are Rinnai, Noritz, and Navien - all use 2" PVC vents... Also, high efficiency furnaces (HVAC) use 3" vents for many years...

Yes, Milo and ballengerb, you are correct, PVC is widely used to vent gas appliances, however, Carol Fey, a well recognized expert and trainer of hydronic control systems, has written a very informative article - " Risk of using PVC for boiler venting '' in a recent edition of Contractor Magazine.
I was involved in the Plex - vent / Ultravent recall fiasco in the 1990's, and, many believe PVC will follow the same path. I have first hand experience of PVC vent pipe playing a role in heat exchanger corrosion, especially, when combined with contaminated combustion air, lack of routine maintenance, and poor installation practices.

There are at least two approved products for venting gas appliances - stainless steel, and polypropylene pipe. In light of the fact that the manufacturers of pvc pipe do not test, rate, or, approve the use of their products for flue gas venting, we have stopped using it...............

Mike45plus, I have been using Schedule 40 PVC pipe for power vent hot water tanks for as long as power vent tanks have been on the market with no problems along with a condensation line on the power vent as per hot water tank manufactorers instructions and according to regulations per government new energy codes as of April 2015 and hot water tank manufactorers requirements, Schedule 40 PVC pipe vents will be required on hot water tanks 55 gallons or bigger.