Immersion heater in hot tank: Problem

rock22

I have a 10 yr old hot water tank with plug at top for fitting immersion heater. However I have had no luck removing the plug ( which seems stuck!).

My question . Can a plumber fit cut and tap anothe rart of the tank top for an immersion heater?
Or do I need to fit a new tank?

Thanks

ntpm

rock22 wrote: »

I have a 10 yr old hot water tank with plug at top for fitting immersion heater. However I have had no luck removing the plug ( which seems stuck!).

My question . Can a plumber fit cut and tap anothe rart of the tank top for an immersion heater?
Or do I need to fit a new tank?

Thanks

Couple tricks can be used to try and release the brass boss fitting.

1. Try and lightly hammer/tap the fitting gently while turning the spanner clockwise(to tighten) and then turn it anti-clockwise.
Lighlty hammering will crack some of the compound/sealing paste.

2. Apply a little heat on the brass boss fitting using a blow torch. Ensure the copper of the cylinder does not get too warm as it may split or warp when you try to loosen it.

Is your cylinder a pre insulated one... if not it may be worth replacing it at this stage.

aujopimur

If you keep the cyl. full of water it keeps it steady when you try to loosen the flange.

Joey the lips

The tricks above work great but be careful. The brass nut is stronger than the copper cylinder. I have seen the cylinder kink. The reason the nut is stuck is prob boss white so make sure you have some seal for afterwards. Plumbers thread lock works great for DIYERS. not that you are one but just in case.

rock22

Thanks for those ideas.
i have tried heating and tapping gently. Unfortunately without any movement and the dome of the tank is beginning to kink. i assume it is not possible to cut another opening for the heate?

thanks again for helpful replies

Sparkpea

why not just fit a willis type immersion on the outside of the tank and leave that plug alone?

Joey the lips

Sparkpea wrote: »

why not just fit a willis type immersion on the outside of the tank and leave that plug alone?

I was wondering about that myself... I cannot remember how that works...Is it a instant water heater or does it only heat whats in the tube

Sparkpea

internal immersion heats from the bottom of the tank up, so takes a good hour to have hot water at the tap

willis type is more instant like a kettle and heats from the top of the tank down. so say you have it on for 10mins you'll get enough water to wash some dishes and have a shave/wash etc.

if you want a bath then you need to leave it on for an hr or so anyway

most new cylinders come with a 1/2" boss so I would fit my willis type into that and tee off that pipe for a drain off, whereas I'm guessing you guys would put a drain or plug in it

if theres no boss then fitting an essex boss is easy enough

Joey the lips

Sparkpea wrote: »

internal immersion heats from the bottom of the tank up, so takes a good hour to have hot water at the tap

willis type is more instant like a kettle and heats from the top of the tank down. so say you have it on for 10mins you'll get enough water to wash some dishes and have a shave/wash etc.

if you want a bath then you need to leave it on for an hr or so anyway

most new cylinders come with a 1/2" boss so I would fit my willis type into that and tee off that pipe for a drain off, whereas I'm guessing you guys would put a drain or plug in it

if theres no boss then fitting an essex boss is easy enough

You can always use the sink part of a standard heating element to heat quicker...


Havin said that I know the willis heater to be good..


http://www.willis-renewables.com/immersion-how-it-works.htm

Sparkpea

what do you mean by the sink part?

handy site and diagram that. some installers actually pipe it into the cold feed as its coming into the tank but I hate that idea. Also the immersion tee should be about 16" above the top of the tank for best results incase anyone who reads this is thinking of doing it!

rock22

Thanks for the idea about this. In fact i have one fitted but it is fed from a tee off the cold feed to the tank.
The problem with that type of fed, is that when the hot tap is opened it takes feed from cold feed and from tank.

For the moment I think I will leave things as they are

thnaks again for all the information

aujopimur

You could have a problem with the location of coil if you try to use an alternative position for the immersion.By the way where are you located.

Sparkpea

^^^ if you use an essex flange then yes you will need to make sure its below the coil return.

I agree being fed from the cold feed can cause that problem of it drawing cold water than hot. I'd blank off that tee or fit a ballofix as a drain and use the essex flange, seen here

http://www.toolstation.com/images/library/stock/webbig/93835.jpg

you drill a hole in the tank which is smaller than the washers (all instructions included) and a washer and split locknut goes into the hole and held by the metal rod shown while u put the washer and lockout on the outside and tighten. If you already have a willis in place then its just a matter of altering the pipework to it so its even easier to do for you than when I first posted.

anyway good luck with whatever you decide