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Matthew Liang
08-16-2012, 10:24 PM
I am a new CAHPI(BC) candidate. I inspected my friend's home today as a practice. I found that the hot water supply pipe near the tank is red plastic. I remember that the hot water pipe has to be copper within 18' close to the tank. Is it okay to use this find of plastic pipe. Sorry that the picture is blurred.

Any comment is appreciated.

Tom Rees
08-17-2012, 07:05 AM
In my area it's not ok to have pex within 18" oy top of water heater (I'm assuming that's pex). Is that gray pipe you can see in the wall behind heater polybutylene?

John Kogel
08-17-2012, 07:17 AM
Red, blue or bright white flexible pipe is most likely to be PEX.
Instead of 'plastic' try to use the correct terms like poly or vinyl or PolyB or Pex or PVC.
The hard cream colored pipe is CPVC. You will find that occasionally, no longer used.

PEX can handle the heat of the water heater, and we see it used that way fairly often, such as if a new tank has been installed in an older house. It is incorrect by the rule.

Scott Patterson
08-17-2012, 07:31 AM
Yes, the PEX can handle the hot water but not the hot exhaust gas from the burner.... You need to see 18" of metal pipe and then the PEX.

Matthew Liang
08-17-2012, 08:18 AM
Thanks everybody for your comments.

Tom, the gray pipe is PolyB which is used for all the supply pipes.

So, I can conclude that the red pipe is PEX and it is too close to the heater.

Bryce Jeffrey
08-17-2012, 08:46 AM
Kitec Plumbing Systems Class Action | Products Liability Class Actions, Kitec Plumbing Systems Class Action Lawsuit - Class Action Canada (http://www.classaction.ca/actions/products-liability/current-actions/kitec-plumbing-systems.aspx)

Mark Fisher
08-17-2012, 08:58 AM
At minimum I always recommend that nothing that can melt or burn be within 6" of a flue pipe.

Scott Patterson
08-17-2012, 09:21 AM
Thanks everybody for your comments.

Tom, the gray pipe is PolyB which is used for all the supply pipes.

So, I can conclude that the red pipe is PEX and it is too close to the heater.

It is too close to the water heater exhaust, not the heater. You need to be specific with what you are trying to convey to your client.

Matthew Liang
08-17-2012, 09:36 AM
It is too close to the water heater exhaust, not the heater. You need to be specific with what you are trying to convey to your client.

Thank you so much, Scott.

Joe Hendrix
08-17-2012, 02:36 PM
I know that the post is about the PEX pipe being too close to the water heater so I might be amiss but there might also an issue with the class b gas venting. I have never seen class b gas vent crimped. From the picture it looks like it might have been hand crimped at that.

Jim Robinson
08-17-2012, 03:03 PM
I don't think that it B vent in the photo. The B vent probably (hopefully) starts above the photo. Probably single wall, hence the six inch space needed for the pex.

Matthew Liang
08-17-2012, 03:30 PM
I don't think that it B vent in the photo. The B vent probably (hopefully) starts above the photo. Probably single wall, hence the six inch space needed for the pex.

Hi Joe and Jim,
Thank you for your comment.

It is not B-vent. It goes up to join the former furnace vent, then to B-vent. See attached picture.

Actually I cannot figure out what the pipe is at the corner. It is goes up into the ceiling and down to the crawlspace.

Jerry Peck
08-17-2012, 04:44 PM
Actually I cannot figure out what the pipe is at the corner. It is goes up into the ceiling and down to the crawlspace.

Radon mitigation exhaust?

Matthew Liang
08-17-2012, 06:04 PM
Radon mitigation exhaust?

Hi Jerry,
I have no idea about Radon test. This is a house in Vancouver BC Canada close to US border.

Could someone shed a light on this?

Jerry Peck
08-17-2012, 06:31 PM
Hi Jerry,
I have no idea about Radon test. This is a house in Vancouver BC Canada close to US border.

Could someone shed a light on this?

Matthew,

Let's hope some of the people who do radon and know about radon mitigation respond - that is something I know little about.
But I think I know that sucking the radon out of the crawlspace and dumping it into the attic is not a good thing ... does that duct go outside or end in the attic? Heck *I* would not even want a radon duct 'going through the house' in case there was any leakage.

John Kogel
08-17-2012, 06:43 PM
There's no significant uranium in the ground so no radon threat in that part of the world.

Maybe it's a dryer vent. Can't tell without more info.

Bob Harper
08-17-2012, 06:46 PM
Unlisted firestop, improper support, no firestop for pipe in corner regardless of whatever it is. Yes, 6" clearance off single walled vent connector.

Radon mitigation is under positive vent pressure downstream of the inline blower so it should not be within the structure and discharge into the atmosphere-not attic. Radon mitigation is usually done with sch. 40 pvc cemented joints. INFILTEC Air Leakage Control - Radon Gas Mitigation & Blower Doors - test, testing (http://www.infiltec.com/)

HTH

Tom Rees
08-18-2012, 06:20 AM
Could that pipe in corner be bringing in combustion air from attic. Sorry, I just went back and looked at post, didn't see the part where it goes down into the crawl space. Is furnace in crawlspace?

Scott Patterson
08-18-2012, 07:09 AM
Report it as an unknown pipe in corner..... :)

Jerry Peck
08-18-2012, 10:55 AM
Report it as an unknown pipe in corner..... :)

We know the pipe ... its name of Fred, what we do not know is why Fred is there and why it goes from the crawlspace and up through the ceiling. :)

Matthew Liang
08-21-2012, 09:29 PM
Report it as an unknown pipe in corner..... :)

Thank you, everybody, for your comment. I came to the house again today and found out that the pipe is a hot air supply pipe from crawlspace to 2nd floor bathroom.

Garry Sorrells
08-22-2012, 03:57 AM
Radon mitigation needs a sealed conduit between the source and the exterior of the structure . PVC is used because it can be chemically bonded at the unions forming a continuous sealed conduit to remove the gas from under the basement slab.

H.G. Watson, Sr.
08-22-2012, 11:06 AM
There should be no combustible form of tubing or piping in the top zone of the Cat. I fuel-fired water heater. That area is all encompasing to its diameter and for a height determined by its listing/approval (instructions) and venting type.Clearance to front of water heater, burner plate, no safe pan or drainage for same, TPRV discharge too high from floor, floor unprotected from same, no conversion to drainage, no proper termination of same; no sed trap before gas valve of appiance, improper shut-off valve, etc. etc.temperature transfer to hvac duct, leakage/spillage to hvac return.There are critical issues regarding the double draft hood, tape, clearances (not just to combustibles but required air space, heat reflective materials, form, sizing, non-support, configuration and manner of vent connector to b-vent system, more tape, etc. and sizing/configuration of orphaned gas-fired appliance venting. Dissimilar metal connections, heat sink, exposed insulation facing, holes in gyp separation, and many other issues referenced in your two other discussion topics wherein you've sprinkled additional photos of the same cluster of defects.

Bruce Ramsey
04-21-2015, 02:37 PM
Who makes the rule that it cannot be plastic within the first 18 inches? Is it code or manufacturers installation instructions? Looking for a reference please.

Yes, I agree that it does not make good sense. Like to have a reference when challenged.

Jerry Peck
04-21-2015, 02:48 PM
Who makes the rule that it cannot be plastic within the first 18 inches? Is it code or manufacturers installation instructions? Looking for a reference please.

Yes, I agree that it does not make good sense. Like to have a reference when challenged.

Depends. Heat sources? Electric water heaters? Gas water heaters?

http://www.cbsupplies.ca/guides/VG_PEX_install_Guide.pdf (go to page 16 & 18)

Bruce Ramsey
04-21-2015, 03:06 PM
Ok. Good. Thank you. The PEX manufacturer says must be 6 inches from heat source for PEX.

Lots of CPVC in my area. Got a reference for other than PEX?

Jerry Peck
04-21-2015, 03:24 PM
The PEX manufacturer says must be 6 inches from heat source for PEX.

Are you referring to a specific manufacturer when you say "The PEX manufacturer says must be 6 inches" or to that link?

For CPVC: https://www.ppfahome.org/pdf/PPFA_CPVC_Installation_Manual_2006.pdf (go to page 6, Water Heater Connections)

Bruce Ramsey
04-21-2015, 04:11 PM
Are you referring to a specific manufacturer when you say "The PEX manufacturer says must be 6 inches" or to that link?

For CPVC: https://www.ppfahome.org/pdf/PPFA_CPVC_Installation_Manual_2006.pdf (go to page 6, Water Heater Connections)

I was referring to the link you provided. Thank you for the two links.

Jerry Peck
04-21-2015, 04:18 PM
The PEX manufacturer says must be 6 inches from heat source for PEX.


I was referring to the link you provided. Thank you for the two links.

That's not what that link says.

Page 16 says a minimum of 12" above, and a minimum of 6" horizontally from, a high heat producing element such as recessed lights, vents, etc.

However, on page 18 it says that a minimum of the first 18" above a gas water heater needs to be metal ... not withstanding that the 6" horizontally shown on page 16 still applies to the PEX beyond that first 18" of metal pipe.