Hard Water / Water Heater

[terptide]

Question for the happy homeowners out there. In a VM home approx 5 years old. The intake copper pipes feeding into the water heater have seemed to excessively corrode just over the past 6 months. Heavy corrosion that is green and white right on the joint above the heater.
My guess is that it is dielectric corrosion - does any body out there have theirs grounded>?

Thanks in advance for any input

[Dwarflord]

Im not real sure about the problem being dielectric corrosion, but my experience has shown this to be a problem on 2 accounts.
1) The temperature of the water heater is too high. Usually most electric water heaters have 2 elements in them. When one starts to go bad, it usually doesnt cycle to the "off" state and the water temperature almost reaches boiling.
2) The copper joint may not be soldered correctly - maybe a very very small leak. Add this with the possibility of the high temperature and and you have a small steam leak.
Our water in this area is very hard, which means it has a lot of calcium and magnesium ions in it. When these ions precipitate (come out of solution) they tend to be of a white hard crystalline nature, which may be what you are seeing.
This is what I would recommend to check. Check both your heating elements in your hot water heater to make sure they are operating correctly. If not, they are very easy to replace and inexpensive. In my last home I had electric water heater and myself and some other neighbors had to replace elements around the 6 year mark, you may have a similar situation.
Other points Ill add too, I recommend to purge your water heater at least 1 time every 2 years, prefer once a year. Make sure you turn off the electric to the water heater before you drain your tank, otherwise youll burn them up. This keeps the buildup of iron sludge, magnesium and calcium (along with other nutrients) from building up in the bottom of the tank and causing the osmotic pressure to build. As the osmotic pressure builds, it takes more energy (entropy) to heat the water, thus premature burnout on your heating elements.
I may have given too much info, but I hope it helps and at least gives you something to go looking into to fix the problem. Let us know what happens.

DwArFlOrD

[WesGurney]

We had this exact same problem, except it started showing up about 6 months after we had moved in. It was also slightly wet near the joint of the intake valve on the hot water heater. The fix was to replace the intake joint (the piece that screws into the hot water heater valve and is the soldered to water supply). After they replaced the joint the problem went away. I never really got an exact answer as to what the cause was, but my guess is that its either a leak in the joint or it wasn't screwed in tight enough into the water heater and water could slowly leak out.

One last piece of advice is to make sure that when you replace the joint, the threads are wrapped with this white tape (not sure what the exact name of the tape is). It is supposed to make the seal extra tight so no water can escape.

Good luck!

[sunnydog]

the white tape is plumbers tape.
we had a similar problem on our washing machine and once it was cleaned and resealed with thredded tape we were good to go.

[TigerFan]

I've never drained or purged my gas water heater. Would someone post instructions on how to do this. Maybe another idea for a new topic would be "maintenance for the novice homeowner" for eveything else I should be doing to my appliances.

[Dwarflord]

quote:Originally posted by sunnydog

the white tape is plumbers tape.
we had a similar problem on our washing machine and once it was cleaned and resealed with thredded tape we were good to go.



Its also called Teflon tape. Very inexpensive, but works for almost all threaded piping for water or gas.

DwArFlOrD

[terptide]

quote:Originally posted by Dwarflord

Im not real sure about the problem being dielectric corrosion, but my experience has shown this to be a problem on 2 accounts.
1) The temperature of the water heater is too high. Usually most electric water heaters have 2 elements in them. When one starts to go bad, it usually doesnt cycle to the "off" state and the water temperature almost reaches boiling.
2) The copper joint may not be soldered correctly - maybe a very very small leak. Add this with the possibility of the high temperature and and you have a small steam leak.
Our water in this area is very hard, which means it has a lot of calcium and magnesium ions in it. When these ions precipitate (come out of solution) they tend to be of a white hard crystalline nature, which may be what you are seeing.
This is what I would recommend to check. Check both your heating elements in your hot water heater to make sure they are operating correctly. If not, they are very easy to replace and inexpensive. In my last home I had electric water heater and myself and some other neighbors had to replace elements around the 6 year mark, you may have a similar situation.
Other points Ill add too, I recommend to purge your water heater at least 1 time every 2 years, prefer once a year. Make sure you turn off the electric to the water heater before you drain your tank, otherwise youll burn them up. This keeps the buildup of iron sludge, magnesium and calcium (along with other nutrients) from building up in the bottom of the tank and causing the osmotic pressure to build. As the osmotic pressure builds, it takes more energy (entropy) to heat the water, thus premature burnout on your heating elements.
I may have given too much info, but I hope it helps and at least gives you something to go looking into to fix the problem. Let us know what happens.

DwArFlOrD

[neilz]

quote:Originally posted by TigerFan

I've never drained or purged my gas water heater. Would someone post instructions on how to do this. Maybe another idea for a new topic would be "maintenance for the novice homeowner" for eveything else I should be doing to my appliances.


OK ...

1. Get garden hose.
2. Attach female end of hose from step 1 to hose bib located at bottom of water heater.
3. Put male end of hose in house sump or direct out basement window or door.
4. Open hose bib from step 2, allow water to run for 5 minutes or so to flush sediment from tank.
5. Close valve and remove and put away hose.


I know they are very simplistic, but as you can see, there's really nothing to it. :D

Neil Z.
Resident since 1999

[afgm]

You've broken it down well Neilz. Of note, if you dump the water into your sump pump be cognizant of where the water goes. It is very hot water, and if the water is expelled onto the lawn, it can kill the grass, due to the heat of the water.

Also, remember to turn the water heater off before beginning the process.

quote:Originally posted by neilz

quote:Originally posted by TigerFan

I've never drained or purged my gas water heater. Would someone post instructions on how to do this. Maybe another idea for a new topic would be "maintenance for the novice homeowner" for eveything else I should be doing to my appliances.


OK ...

1. Get garden hose.
2. Attach female end of hose from step 1 to hose bib located at bottom of water heater.
3. Put male end of hose in house sump or direct out basement window or door.
4. Open hose bib from step 2, allow water to run for 5 minutes or so to flush sediment from tank.
5. Close valve and remove and put away hose.


I know they are very simplistic, but as you can see, there's really nothing to it. :D

Neil Z.
Resident since 1999

[TigerFan]

Thanks