Get a socket or ring spanner on the fitting and give a sharp tap with a hammer. Hold firm as to undo a bit in from end then hit out on end to assist the pulling pressure. Will have much more effect than just pulling. Don't put your finger between hammer and ring spanner as it will soften the hit, among other issues. Better with a larger hammer rather than a little tack hammer.
Thank you bazza. I cracked it and covered myself with crap. I guess I should have emptied the tank first . The anode was well and truly stuffed . Next time I will inspect it every 6 months like I was told to.
Thank you bazza. I cracked it and covered myself with crap. I guess I should have emptied the tank first . The anode was well and truly stuffed . Next time I will inspect it every 6 months like I was told to.
Don't forget to use white teflon thread tape on new anode, ensuring the tape is on all the thread, easier to get out that way.
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Why is it so? Professor Julius Sumner Miller, a profound influence on my life, who explained science to us on TV in the 60's.
I am sure you know that the anode support has to to have good electrical contact to the HW cistern shell
That is required for for sacrifical anode, cathodic protection to work.
It requires a closed circuit via the water
Th eanode's purpose is to protect any small defects/ holes in the liner ,from leading to corossion of the shell
It is also a very low voltage output, so Heavy taping of the thread COULD insulate the anode from the steel shell
IF the threads do not makeelectrical contact , how can the anode function ??
OR do you know something??
A small amount of tape on the last of the treads is usually ok
BUT always a good idea when using tape to insure there is metal to metal contact
PeterQ
-- Edited by oldtrack123 on Wednesday 19th of March 2014 06:43:13 PM
Having worked with cathodic protection systems for over 40 years, I'm satisfied that I have a passing knowledge of the principles of operation.
First point is that the anode nut and its female counterpart in the tank have tapered threads, this means that the further you screw them together, the tighter they become.
It is therefore nigh on impossible to tightly couple teflon taped tapered threads without the teflon being removed from the rear flanks of the threadform and deposited between the crests and the roots, and this is what the tape is intended to do and is where water will trek if possible.
As the nut tightens, the teflon will be removed from the trailing edges of the thread as this is where the load is applied, and this is where the electrical contact will be made.
Teflon also has lubricating properties which will make assembly and dis-assembly that much easier.
Second point is that the manufacturer of the tank tells us to use it, so who are we to argue?
The ONLY manufacturer of lined steel tanks that does not recommend the use of teflon tape on their anodes is Solahart, and that is because they employ a non-tapered thread with a dual O ring seal.
If you are really concerned about the contact, then put an Ohm meter across the nut and the tank shell immediately after inserting the anode before filling with water, if the reading is a bit high, give the nut another tweak.
Second point is that the manufacturer of the tank tells us to use it, so who are we to argue?
If you are really concerned about the contact, then put an Ohm meter across the nut and the tank shell immediately after inserting the anode before filling with water, if the reading is a bit high, give the nut another tweak.
HI Brian
[a]I am not arguing against the use of teflon tape but warning that excess use can lead to problems, especially IF the connections is only tightened to the non leaking stage
Of course the advantage of a tapered thread is it's inherent better sealing capablity, but it still often needs a little thread sealer
After all it is not a high pressure connection [30 to 40PSI in most cases]
YES
that was my point with"
"BUT always a good idea when using tape to insure there is metal to metal contact"
Much better than finding out too late, that the anode was not doing much in the way of protection
