Removing Heat Trap Nipples - SURPRISE - SEE POST # 6

[TVL]

I am in the process of getting everything together to change out an old water heater. Based on what I have seen in the store, it appears most all water heaters now come standard with galvanized heat trap nipples already installed. I want to remove them and replace them with brass hardware, which will then connect to my homes copper piping.

From what I've read, it appears the heat trap nipples can be a big challenge to remove .................. that is unless the manufacturers have recently made improvements in this area. So, what is the best method to remove these nipples? I was hoping I could just put a pipe wrench on the nipple and simply unscrew it, but it doesn't look like it will be that easy.

Thanks for any suggestions!

Just as info: I'm looking to purchase an AO Smith water heater, but I've looked at the Rheem units as well. I will need a 38 gallon lowboy unit to properly fit the location as it is underneath the house.

 

[Jadnashua]

You may just need a bigger wrench, and to keep from just rotating the tank, maybe a means of keeping it from rotating. It is a threaded connection.

 

[Sponsor]

 

[Dj2]

A galvanized piece of pipe over the wrench handle will give you more torque. You may need a second person to hold the tank from rotating.

If you lay the WH on a blanket on the floor it will be somewhat easier. Here a 24" wrench can do the job. Be careful not to break the nipples.

 

[TVL]

Thanks for the replies thus far!

The reason for my post is that after some online research, I discovered that there were several individuals who have attempted to remove the heat trap nipples from new units, and in the process, the nipples were easily crushed. It then appeared things got worse from that point on. So, I was hoping someone on this forum had experienced this issue firsthand and had discovered a method for easily removing the nipples. I would have thought that removing a nipple from a NEW water heater would have been a very easy task .................... but, it doesn't appear so!

 

[Jadnashua]

The manufacturer does not expect you would ever remove or replace these, so they (probably) use a power tool to get them screwed in very tight to ensure there are no leaks - far more than you'd normally do if a real person was doing it. The pipe dope probably doesn't help, either. As a result, it can be a bear to remove. On say the sacrificial anode, you can put an impact wrench on it. Somebody may make an impact pipe wrench, but it's not something the average person would own. Usually, they'll last as long as the rest of the thing, so while preemptively replacing them now may help, it may not in the long run.

 

[TVL]

I took the time to write AO Smith and Rheem to get their opinions on how to easily remove the factory installed nipples, which also have the dielectric inserts and a rubber flapper "heat trap". And I've got to say, I'm very glad I did!!

AO Smith is the only one that has replied as of yet, but they actually took the time to contact me by phone so that we could discuss the matter in detail. Long story short, the dip tube used to direct water to the bottom of their tank is CONNECTED or PART OF the nipple. If you remove the nipple, you also remove the dip tube AND you just can't simply replace the dip tube and another nipple of choice as there isn't anything to hold the dip tube in place.

I am a little disappointed in what I learned, because I really wanted to replace the steel nipple with a brass unit. Because of what I've read on the internet, I feel this will be the weak point on the heater, but it appears I will now have to accept what comes installed on the heater.

Anyway, thanks for any replies!

 

[LLigetfa]

which also have the dialectric inserts and a rubber flapper "heat trap".

I have not heard anything bad about the rubber flapper type of heat trap and the dielectric should minimize mineral buildup. IMHO it is the floating/sinking ball type of heat trap that can be problematic. The ball type can purportedly be pulled out without removing the nipple.

 

[TVL]

IMHO it is the floating/sinking ball type of heat trap that can be problematic

Thanks LLigetfa!

1- You're very correct about the ball type heat traps being problematic ................... at least that is what I've read!

2- I really did not care about any type heat trap as my water lines are insulated. I will probably try to remove the "rubber flapper" if it's easily done.

3- Knowing the nipples are of steel construction, my main objective was to replace them with brass or stainless hardware. Anyway, that doesn't appear to be an option since the dip tube is part of their nipple!

4- You stated: "the dielectric should minimize mineral buildup" ............. are you indicating the dielectric insert inside the nipple will actually help reduce corrosion of the steel nipple? I do realize the primary purpose of a dielectric connection is to minimize galvanic corrosion of two dissimilar metals, but will the dielectric insert also help with corrosion when dissimilar metals aren't joined and this is not a concern?

 

[LLigetfa]

Don't confuse dielectric union with dielectric nipple. On the union, the intent is to keep the different metals from touching each other which forms a weak battery. On the nipple it is just so that minerals don't have an easy place to attach to and build up.

 

[TVL]

Don't confuse dielectric union with dielectric nipple. On the union, the intent is to keep the different metals from touching each other which forms a weak battery. On the nipple it is just so that minerals don't have an easy place to attach to and build up.

Thanks! I was thinking they were basically used for the same thing ............. to separate two dissimilar metals. So, maybe the pre-installed steel nipples won't corrode as quickly as I had thought. I guess time will tell!

 

[Reach4]

On the nipple it is just so that minerals don't have an easy place to attach to and build up.

I think it is more than that... make the ions in the water to have to travel a longer path through water to go between dissimilar metals.

The bottom of the nipple will be steel to steel. But the top of the nipple (on a top-mounted nipple) will be connected to a different metal. You don't run CPVC right to the nipple. You need 18 inches of metal.

I don't have a good picture in my head of how it all works. But remember Valveman has had very good corrosion-preventing results by wrapping good electrical tape around galvanized pipe connecting to other metals.

 

[LLigetfa]

The bottom of the nipple will be steel to steel. But the top of the nipple (on a top-mounted nipple) will be connected to a different metal. You don't run CPVC right to the nipple. You need 18 inches of metal.

Isn't that where the dielectric union would go? Steel-to-steel and brass-to-brass.

 

[Michael Cole]

TVL: The matter that your dip tube is connected to the cold water heat trap nipple does make it easy to change the dip tube but you would need a flexible hookup that allows clear space above the dip tube if it is a shgort enough water heater.

If your hot water pipes are insulated a hot water heat trap nipple is unnecessary. If you are using gravity or forced recirculation of hot water you should use a dedicated recirculation heat such as the American Standard CE-6-AS water heater which has both top and side connections. The traditional method of gravity hot water recirculation can allow cold water to back flow off of the the bottom of the main tank which is a problem that Friends of the Homeless in Columbus, Ohio has when 2 or more people are taking a shower. We would have to turn on an extra shower to intercept the backflowing cold water. I do not recommend the 2.5 gallon version because that does not have magnesium anode to prolong the life.

The top cold water inlet and the side hot water outlet of this midget heater should be equipped with boiler drains or other type of hose faucet to enable purging air from the tank. You might also need some hose faucets elsewhere to help purge when filling or refilling the system. Alternatively, the top cold water inlet can be equipped with both a hose faucet and a permanent valve from the cold water line to facilitate filling the midget heater and the hot water recirculation lines.

Also, do not forget an expansion tank for your main hot water tank.

What you would do with this auxiliary midget water is to use nipples e.g. brass that do not act as heat traps and connect the gravity or forced recirculation line to the side bottom "cold" inlet. You would connect the top hot water outlet of the midget heater to a tee that is just above the heat trap nipple of the main heater. You should downsize the heating element to 750 watt or 1,000 watts at 120 volts. You even downsize to 500 watts at 120 volts by putting in a 2,000 watt 240-volt element. This way you can replace your garbage disposer control switch with a motor rated 3-way switch. I have done this to put an InstaHot on the same circuit as the garbage disposer. Considering that garbage disposers are required now to be on a dual function GFCI + AFCI circuit breaker even though it runs for just a few minutes per day you might as well make the garbage disposer circuit a 20-amp circuit and use 20-amp or better yet 30-amp motor rated 3-way switch to allow something else to SHARE the same circuit when the garbage disposer is not running.

One reason for using all 20-amp wiring and 20-amp AFCI circuit breakers which are expensive enough that you might as well have the extra capacity of a 20-amp circuit. Also, 1/3rd HP garbage disposers are junk and nuisance trip their own overload relay too frequently. a 1/2 horsepower garbage disposer should be considered a varying duty motor that requires a motor circuit that is rated for 200% of motor full load current which is a National Electrical Code requirement for motors that are subject to deliberate overloads. A 20-amp 120-volt circuit will run any househgold garbage disposer up to 1 HP which has enough oomph that it just about will never overload unless jammed.

My Ohio electrical contractor license number is EL45,008. I am trained to do both electrical and plumbing i.e. I know how to do plumbing in general and electrical pipe is just a particular set of pipes and pipe fittings. I have actually used my rigid conduit bender to bend gas pipe - if it hurts the integrity of the pipe I would ot be allowed to bend explosionproof electrical pipe.

 

[Michael Cole]

Also, your hot water supply and return lines need to be insulated EXCEPT the top 4 feet or so of the return line for gravity recirculation to to work. Only the top end of the return line has to cool down to establish the greater weight of water in the return line.

Also, if a gravity hot water recirculation loop starts with a basement hot water tank and goes up to the second floor or higher the hot water supply and return lines at the elevation of the basement ceiling can have a 1-foot dip down and back up again and gravity recirculation will still work. You just need to have an automatic air vent where the horizontal return line goes back up from the dip to get ride of air bubbles same with hot water supply if there is no faucet that acts as an air vent. Caution: The air vent needs to be rated 60 PSI preferably 100 PSI. The usual kind of automatic vents for typical forced hot water heating do not enough pressure rating for potable water.

Going through homelessness is NOT the way to find a a Real World instance of cold water backflowing off of the bottom of the main hot water tank and through the hot water return line and into the hot water supply line!

Just my $2 ( inflation ) part on these subjects.