Steps to replace water heater inlet?

tondar · 12-22-2008, 08:40 PM

The inlet to my water heater has looked like this for a long time. I know I should have fixed this long ago but I didn't. I noticed today there was a little drop of water on the outside of the corrosion. I need to replace this now, not sure exactly what caused this though.

So I am relatively mechanically inclined but I haven't had to replace any metal piping yet. I don't even recognize how this pipe is attached to the heater inlet. Do I turn the big nut to break the connection while holding the nut below it? Will I have enough room to get the piece of pipe under the shutoff valve out of there?

I would greatly appreciate any help with how to get started on this.

Thanx

**Termite** · 12-23-2008, 02:01 AM

The big nut you're referring to is called a union. Yes, you turn the big part while holding the smaller part. The union will come apart when the big part is unscrewed, allowing you to remove pipes. The union goes back together with no pipe dope. Use pipe dope or teflon tape (a few wraps) to connect the pipes to the union.

Now...I see a problem here. Those are normal pipe unions. That's great for an installation somewhere else in the house or on a gasline, but they're no good for water heater installations. Those unions should be dielectric unions, not regular unions. There should be an 8 gauge copper wire jumping from hot to cold above the unions to ensure electrical continuity of your home's grounding system.

The pipe that threads into the top of the heater is a 3/4" pipe nipple, and that joins to the union. I doubt that removal of that 3/4" nipple will be easy at all.

The minerals in the water and electrolysis will attack metals in the water heater and supply plumbing. The water heater has/had a metal anode rod that serves as a sacrificial hunk of metal for them to eat instead of eating the tank itself or the associated metal parts. Depending on the water in your area the anode rod might last a year, it might last 14 years. When that anode rod is gone, start kissing the rest of the system goodbye. From the looks of things, I'd bet yours is gone.

Your water heater looks very old and it might be worth considering a total replacement. Transitioning from your pipes to a new water heater would be an easy task.

majakdragon · 12-23-2008, 11:09 AM

Looks like you may need to replace the union and the nipple above it going into the valve. Use two wrenches to prevent stress while disconnecting. Take any suspect parts with you when shopping for replacements. I disagree with kctermite on the dielectric union. You have all galvanized water lines so you are not changing material, to copper or brass, and there would be no electrolosis occuring. (this is the reason for installing dielectric fittings) Not sure if your waterlines are serving as a ground for your electrical service, but may well be true. This would be a reason for a jumper.

tondar · 12-23-2008, 12:43 PM

where is this metal anode rod? I take it this is something I can replace?

thanks

majakdragon · 12-23-2008, 01:09 PM

Most anode rods are located in the top of the water heater. Looks like a plug. Turn off the cold water inlet and turn the control valve to the off position. Drain about 3 gallons of water out of the tank. Now comes the hard part. Unscrewing this plug can be a pain in the butt. Seems manufacturers like to make sure they will never leak. You will need the make and model number of your unit to purchase a replacement. Use teflon tape on the threads when installing the new anode rod.

47_47 · 12-23-2008, 02:38 PM

I would also change the dip tube when you fix the supply. A dip tube is a plastic tube in the inlet of the water heater, which sends the incoming cold water to the bottom of the tank to be heated.

12-22-2008, 08:40 PM	#1
tondar Newbie Join Date: Dec 2008 Posts: 13	Steps to replace water heater inlet? The inlet to my water heater has looked like this for a long time. I know I should have fixed this long ago but I didn't. I noticed today there was a little drop of water on the outside of the corrosion. I need to replace this now, not sure exactly what caused this though. So I am relatively mechanically inclined but I haven't had to replace any metal piping yet. I don't even recognize how this pipe is attached to the heater inlet. Do I turn the big nut to break the connection while holding the nut below it? Will I have enough room to get the piece of pipe under the shutoff valve out of there? I would greatly appreciate any help with how to get started on this. Thanx Attached Thumbnails

12-23-2008, 02:01 AM	#2
Termite Moderator Join Date: Apr 2008 Posts: 6,520	Steps to replace water heater inlet? The big nut you're referring to is called a union. Yes, you turn the big part while holding the smaller part. The union will come apart when the big part is unscrewed, allowing you to remove pipes. The union goes back together with no pipe dope. Use pipe dope or teflon tape (a few wraps) to connect the pipes to the union. Now...I see a problem here. Those are normal pipe unions. That's great for an installation somewhere else in the house or on a gasline, but they're no good for water heater installations. Those unions should be dielectric unions, not regular unions. There should be an 8 gauge copper wire jumping from hot to cold above the unions to ensure electrical continuity of your home's grounding system. The pipe that threads into the top of the heater is a 3/4" pipe nipple, and that joins to the union. I doubt that removal of that 3/4" nipple will be easy at all. The minerals in the water and electrolysis will attack metals in the water heater and supply plumbing. The water heater has/had a metal anode rod that serves as a sacrificial hunk of metal for them to eat instead of eating the tank itself or the associated metal parts. Depending on the water in your area the anode rod might last a year, it might last 14 years. When that anode rod is gone, start kissing the rest of the system goodbye. From the looks of things, I'd bet yours is gone. Your water heater looks very old and it might be worth considering a total replacement. Transitioning from your pipes to a new water heater would be an easy task.

12-23-2008, 11:09 AM	#3
majakdragon Member Join Date: Sep 2006 Posts: 1,670	Steps to replace water heater inlet? Looks like you may need to replace the union and the nipple above it going into the valve. Use two wrenches to prevent stress while disconnecting. Take any suspect parts with you when shopping for replacements. I disagree with kctermite on the dielectric union. You have all galvanized water lines so you are not changing material, to copper or brass, and there would be no electrolosis occuring. (this is the reason for installing dielectric fittings) Not sure if your waterlines are serving as a ground for your electrical service, but may well be true. This would be a reason for a jumper. __________________ If you have never made a mistake, you haven't done much.

12-23-2008, 12:43 PM	#4
tondar Newbie Join Date: Dec 2008 Posts: 13	Steps to replace water heater inlet? where is this metal anode rod? I take it this is something I can replace? thanks

12-23-2008, 01:09 PM	#5
majakdragon Member Join Date: Sep 2006 Posts: 1,670	Steps to replace water heater inlet? Most anode rods are located in the top of the water heater. Looks like a plug. Turn off the cold water inlet and turn the control valve to the off position. Drain about 3 gallons of water out of the tank. Now comes the hard part. Unscrewing this plug can be a pain in the butt. Seems manufacturers like to make sure they will never leak. You will need the make and model number of your unit to purchase a replacement. Use teflon tape on the threads when installing the new anode rod. __________________ If you have never made a mistake, you haven't done much.

Steps to replace water heater inlet?