Anode Rod and Water Softener

[Sdsvtdriver]

Hi,

I put in a new water heater (AO Smith FCG 75 300) roughly 13 months ago. I have significant corrosion on the dip tube nipple on the cold water intake. AO Smith suggests checking and replacing the anode rod. I did not expect replacing the anode rod to be an annual service item, but I've learned that a water softener greatly accelerates anode rod deterioration. I do not have the option of a second anode rod in this water heater.

I've looked a bit online and I see some powered anode rod devices for this type of application (http://www.waterheaterrescue.com/Longevity/powered-anodes.html). My plumber isn't well versed in these items and the supply house wasn't either. They can order whatever we can use, but I'm unsure what will actually work in this WH.

Does anyone have any experience with powered anode rods? Replacing the anode rod myself is beyond my capabilities at this time and an annual service call will add up fast.

Thanks!

 

[Reach4]

I have the one with the coiled section of wire that you expand to the right length when you install. It is usually used for non-chlorinated water to prevent SRB from reacting with a sacrificial anode. I can see it being of use where your sacrificial anode is getting eaten up too soon. Not cheap.

 

[Sponsor]

 

[Jadnashua]

One contributor here is a big advocate of a powered anode rod...a little search should find it. I don't have any experience with them.

 

[Sdsvtdriver]

I have the one with the coiled section of wire that you expand to the right length when you install. It is usually used for non-chlorinated water to prevent SRB from reacting with a sacrificial anode. I can see it being of use where your sacrificial anode is getting eaten up too soon. Not cheap.

This one? http://www.waterheaterrescue.com/OrderPages/Power-Anode-Coupling.html

Annual anode rod service will cost more than my water heater after a decade, so while this has a higher upfront cost, it should be a one time cost.

I'll do a bit more searching.

 

[Reach4]

This one?

Yes. My WH has a separate anode port, so the tee was not needed.

 

[Sdsvtdriver]

Yes. My WH has a separate anode port, so the tee was not needed.

Can you share the part number? Curious how much power it uses amongst other things.

 

[Reach4]

I bought "SKU27".

There is a little plug-into-the-wall supply.

I don't know the power consumption.

There is a status LED that you should check now and then.

The factories typically torque these much more than needed. If you replace one yourself, you should use PTFE tape, and much less torque than it took to initially remove. Screwing in the anode will cut thru the PTFE enough to make good electrical contact. I suspect about 15 ft-pounds is plenty of torque. Another alternative for you, if access is good is to replace the anode yourself with a thicker anode. That could last a lot longer.

Another thing to consider is whether your anode was as depleted as you thought. To really know that, I think you would want to cut or scrape inside to see if there was magnesium left, but it was covered with white deposits, or if there was only a deposit left on the steel. If you have plenty of overhead access, changing out the anode is a pretty simple job once you have things loosened the first time.

 

[Sdsvtdriver]

Thanks. Any Ceranode part #? SKU27 appears to be a waterheaterrescue.com part number.

I don't have much clearance above the water heater, so a bendable anode would be needed. The whole exercise seems to be a bit more that I'm comfortable with, personally.

 

[Reach4]

Thanks. Any Ceranode part #? SKU27 appears to be a waterheaterrescue.com part number.

http://ceranode.com/index.php?page=domestic-water-header-anodes

Note the link.

The PDF there says

The power supply included is for 100 - 132 volt and requires less than 0.5 watts of power to operate.​

 

[Sdsvtdriver]

Thanks much!

 

[Jadnashua]

Some anodes are not as long as they could be, so you might be able to install a longer one which would last longer than the original.

 

[Sdsvtdriver]

Update: Installed (well, the plumber installed) the CerAnode from waterheaterrescue today. When the old one was removed, I was surprised to see the condition. It wasn't eaten away as I suspected it would be, but coated with a white substance - I'm guessing salt. The rod seemed to otherwise look ok.

https://imgur.com/a/4S19u

I surmise the water softener is set too aggressive. The Fleck 5810 was at 20 for hardness. I set it at 18 today after seeing the anode rod - the number the installer had it set at when it was put in. I likely bumped it to 20 after a water test earlier in the year. I decided to check the city's water report for what they report for hardness. They list 5 sources for water and the hardness is 16, 14, 16, 17, and 4 grains/gal. I grabbed my Hach 5B and did a test and 8-9 drops turned the water blue. Before I screw something up, I wanted to ask - does the Fleck 5810 also measure in grains/gal? I.e should I set the softener to something like 10?

I don't want the CerAnode to get coated with salt also - assuming it functions in the same way - maybe this is a non issue?

I'm a bit surprised at the variation in water hardness over the year but I guess that's to be expected with a source with low hardness nearby.

 

[Reach4]

I was surprised to see the condition. It wasn't eaten away as I suspected it would be, but coated with a white substance - I'm guessing salt. The rod seemed to otherwise look ok.

Take a knife to it. The white may be the remainder of the reaction. If there is still life in the anode, you will have softer shiny metal remaining outside of the center wire.

 

[Reach4]

Update: Installed (well, the plumber installed) the CerAnode from waterheaterrescue today. When the old one was removed, I was surprised to see the condition. It wasn't eaten away as I suspected it would be, but coated with a white substance - I'm guessing salt. The rod seemed to otherwise look ok.

https://imgur.com/a/4S19u

I surmise the water softener is set too aggressive. The Fleck 5810 was at 20 for hardness. I set it at 18 today after seeing the anode rod - the number the installer had it set at when it was put in. I likely bumped it to 20 after a water test earlier in the year. I decided to check the city's water report for what they report for hardness. They list 5 sources for water and the hardness is 16, 14, 16, 17, and 4 grains/gal. I grabbed my Hach 5B and did a test and 8-9 drops turned the water blue. Before I screw something up, I wanted to ask - does the Fleck 5810 also measure in grains/gal? I.e should I set the softener to something like 10?

I don't want the CerAnode to get coated with salt also - assuming it functions in the same way - maybe this is a non issue?

I'm a bit surprised at the variation in water hardness over the year but I guess that's to be expected with a source with low hardness nearby.

10 sounds good initially. If you identify your tank size and BLFC number, I can post the settings I might use. If you know the injector size, I could comment and maybe tune the numbers.

Don't worry about the 20 grain setting having being hard on the WH. The salt used during regen gets washed out, and the amount of sodium entering the water while in service is limited to the calcium and magnesium replaced in the water. However a 20 setting will cause you to regenerate twice as often as a 10 setting.

You can monitor the test point voltage now and then. With red test lead in red, and black into black, that voltage might be -2.5 volts. As I understand it, more negative means there is lower current needed to protect, and less negative would be more current is being used to protect. That might start less negative, and move slowly to more negative with time. Mine started at about -2, and is now -2.6xx. Most people don't monitor even once. They don't need to. I like to watch such things.

 

[Sdsvtdriver]

Take a knife to it. The white may be the remainder of the reaction. If there is still life in the anode, you will have softer shiny metal remaining outside of the center wire.

The knife wouldn't cut into anything. The rod is solid and thick. The white stuff (assuming salt) is now flaky and falls off.

 

[Sdsvtdriver]

10 sounds good initially. If you identify your tank size and BLFC number, I can post the settings I might use. If you know the injector size, I could comment and maybe tune the numbers.

Don't worry about the 20 grain setting having being hard on the WH. The salt used during regen gets washed out, and the amount of sodium entering the water while in service is limited to the calcium and magnesium replaced in the water. However a 20 setting will cause you to regenerate twice as often as a 10 setting.

You can monitor the test point voltage now and then. With red test lead in red, and black into black, that voltage might be -2.5 volts. As I understand it, more negative means there is lower current needed to protect, and less negative would be more current is being used to protect. That might start less negative, and move slowly to more negative with time. Mine started at about -2, and is now -2.6xx. Most people don't monitor even once. They don't need to. I like to watch such things.

I can look on the invoice for the tank size, but what is a BLFC number and where would I find it? Same with injector size. Thanks for explaining what changing the 20 to 10 will do. I'm running KCl so less regeneration saves a bit of money.

I'll pick up a meter and check the reading. I'm curious what it reads now.

 

[Reach4]

The knife wouldn't cut into anything. The rod is solid and thick. The white stuff (assuming salt) is now flaky and falls off.

So sounds like the aluminum+zinc alloy around the steel had not been consumed. The anode material forms aluminum+zinc compounds or magnesium compounds as it gets consumed. That material will of often cling to the steel center as a deposit.

I can look on the invoice for the tank size, but what is a BLFC number and where would I find it? Same with injector size.

Do you have a service manual? It tells where stuff is.

There may be a label. It is probably correct, but not always. You could look at the color of the injector if you want to know. The injector is easy to look at on the 5810. You don't have to pull it out to see the color IIRC, but you do have to take the little dome off by removing the clip while the pressure is released. Releasing the water pressure first is important.

When I put my little cap back, I very lightly lubed the O-ring with silicone grease. I have the grease, so that is not hard.