Help with a water heater issue

[plumbinghelp1]

Hi, I have a water heater, AO Smith, 3 years old. It is in my basement. 2 years ago, I had a kitchen remodel and the venting for the water heater was switched from running up two stories out the roof, to a PVC pipe venting out the first floor, on the side of the house. I noticed that the top of the water heater is very hot, where it is venting out. The plastic/rubber plugs that surround the hot and cold water connections are melting. Today I noticed there is a little bit of water around the cold water plug. Pictures of each plug attached. I called my contractor who did the remodel to get his plumber out here, but I wanted to tap this forum for input, as you have always been very helpful and this is concerning. Am I looking at a simple fix here? Thanks. BK

 

[Twowaxhack]

Take a pic showing the vent piping

 

[plumbinghelp1]

Take a pic showing the vent piping

Here are pics of the pipe. A straight section then a left towards the outside. The rest is hidden by the ceiling. Thank you for your time. BK

 

[Twowaxhack]

Ok, I can’t really say if your vent is improper from the pics but it’s certainly not ideal.

You need twice the vertical height as the vent goes horizontal. So how high is the vent outside compared to the water heater ? If you go 5’ horizontal then you need 10’ of vertical.

Ok, it also looks like it’s single wall and 4”. That’s not good. I’d rather see double wall vent and it be 3”.

Here’s why. 4” Single wall pipe takes longer to heat up and start the draft. It also cools quickly and produces more vent condensation that’s corrosive. The galvy steel will rust out, the 3” double wall has an aluminum inner pipe that will last a lot longer and produce less condensation.

The melting at the top of the heater is a result of diverter spillage. It’s not going to hurt the heater but it’s not ideal because that spillage contains carbon monoxide. They all experience some spillage when they first fire up until the vent heats up enough to start drafting/drawing.

 

[plumbinghelp1]

Ok, I can’t really say if your vent is improper from the pics but it’s certainly not ideal.

You need twice the vertical height as the vent goes horizontal. So how high is the vent outside compared to the water heater ? If you go 5’ horizontal then you need 10’ of vertical.

Ok, it also looks like it’s single wall and 4”. That’s not good. I’d rather see double wall vent and it be 3”.

Here’s why. 4” Single wall pipe takes longer to heat up and start the draft. It also cools quickly and produces more vent condensation that’s corrosive. The galvy steel will rust out, the 3” double wall has an aluminum inner pipe that will last a lot longer and produce less condensation.

The melting at the top of the heater is a result of diverter spillage. It’s not going to hurt the heater but it’s not ideal because that spillage contains carbon monoxide. They all experience some spillage when they first fire up until the vent heats up enough to start drafting/drawing.

Thanks for the info. I have a carbon monoxide detector in the room with the HVAC. Would that be going off if it was spilling out too much? Also, the melting on top and the water that I feel by the plastic stuff that surrounds the pipe connection - is that going to worsen and start shooting out water? There is a lot of corrosion or something on top of the water heater around the vent. My old water heater, venter through the roof was never like that. So, I guess that is an indication that there is definitely more spillage than before. My first concern is safety, second is water filling up my basement. Are either a real possibility? Thank you very much for your time. BK

 

[CT18]

Ok, I can’t really say if your vent is improper from the pics but it’s certainly not ideal.

You need twice the vertical height as the vent goes horizontal. So how high is the vent outside compared to the water heater ? If you go 5’ horizontal then you need 10’ of vertical.

Ok, it also looks like it’s single wall and 4”. That’s not good. I’d rather see double wall vent and it be 3”.

Here’s why. 4” Single wall pipe takes longer to heat up and start the draft. It also cools quickly and produces more vent condensation that’s corrosive. The galvy steel will rust out, the 3” double wall has an aluminum inner pipe that will last a lot longer and produce less condensation.

The melting at the top of the heater is a result of diverter spillage. It’s not going to hurt the heater but it’s not ideal because that spillage contains carbon monoxide. They all experience some spillage when they first fire up until the vent heats up enough to start drafting/drawing.

Two; A lot of cities in my area, Michigan, are mandating that the draft flue pipe be changed to 4" from 3" when switching out water heaters. I am by no means a residential plumber, currently drawing the plumbing for a huge GM plant. I am not sure what there reason was for the switch to 4". I put a water heater in for a friend in one of said cities and had to switch it too 4" as he told me that's what the city told him

 

[DFBonnett]

Same here in NJ regarding the flue pipe.

 

[Twowaxhack]

I don’t doubt what you guys are saying but in my area there are literally thousands of 3” double wall water heater vents that are in service for 38,000 btu water heaters and have been for more than 40 yrs. We all know the water heater drafts better as the vent gets hot and 3” gets hot quicker than 4”.

I encourage everyone to install what your local codes say they want.

 

[TomFOhio]

Take a match or lighter and see if it blows out at the diverter. Doesn't look like its venting properly. If its venting right it should
suck in the match towards the diverter.

 

[pasadena_commut]

Take a match or lighter and see if it blows out at the diverter. Doesn't look like its venting properly. If its venting right it should
suck in the match towards the diverter.

Some bamboo skewers produce a pretty good stream of dark smoke for 10 to 20 seconds if one end is lit and then the flame goes out. I discovered this lighting our water heater, where the dull end of a 12" (ish) skewer is lit with a match until it burns steadily, and then used to light the pilot. The skewers always go out on their own after a while, and if the flame dies on its own there is a period where the dark smoke is produced. I have used this smoke a few times to trace air flow. The end is hot, but not hot enough to keep the bamboo burning, so it shouldn't light other woody substances on fire either. Probably not a good idea to poke one into an area with a gas leak though!

 

[Mitchell-DIY-Guy]

…and the venting for the water heater was switched from running up two stories out the roof, to a PVC pipe venting out the first floor, on the side of the house…

Whoa… you have a conventional gas, water heater, not a power vent or direct vent, and you have changed your vent pipe from galvanized to PVC? I don’t think you can do that…

Was your kitchen remodeling, and all the work associated with it, including this done by permit and inspected? I would check with your town or city, HVAC, inspector, or plumbing inspector, whichever applies to this case. I don’t think you can mix these two vent materials on a conventional water heater.

 

[psomerville]

Whoa… you have a conventional gas, water heater, not a power vent or direct vent, and you have changed your vent pipe from galvanized to PVC? I don’t think you can do that…

Was your kitchen remodeling, and all the work associated with it, including this done by permit and inspected? I would check with your town or city, HVAC, inspector, or plumbing inspector, whichever applies to this case. I don’t think you can mix these two vent materials on a conventional water heater.

I wondered the same thing when I read the post, but I'm not a professional - just a homeowner. I have owned several homes with high efficiency gas furnaces that vented through the sidewall or roof with PVC pipe, but I understand that most of what is vented out is water vapor. I have never had a standard gas hot water heater that vented through PVC pipe - only metal.

 

[TomFOhio]

You are correct. Only power vent water heaters vent with pvc. His water heater is not venting. If he has pvc attacted to
the metal vent he better get it changed out soon.

 

[Rossando]

What's the termination look like? Usually a cap that allows air flow out and no water in is what this type if single wall sheet metal venting uses. Looks kinda like a traditional China hat. How we do it in California is this flue pipe can go to the side of the house but then once outside you add a tee and go straight up and terminate 18" above the roof line.