replacing very old (1938) style immersion heater

[dan_the_plumber]

Hello all

I've got to replace a leaking HWC

I'm fine about doing the job exept where you would normally find a burned out knackered electrical immersion heater there is an essembly that I've not come across before.



View larger image here: 1938 cylinder | Flickr - Photo Sharing!

It is basically 2 half inch pipes coming off what I think is CH circuit just beside the mid position valve and above the pump beside the tank.

These 2 pipes go down into the would be immersion hole.

I can only guess that they are looped and act as a secondary coil?

Since the cylinder is so old I've not come across this before......Has anyone?

Also if I am to reinstall this loop can I get a fitting which will seal the two pipes into the immersion hole?

Maybe I can just chop these two pipes back and cap

Then install a new immersion heater?

I would like to just chop these pipes back, cap and then blank off the immersion hole entirely, but then I'm guessing you'd only get hot water when the heating is on?

Any help greatly appreciated

Dan

 

[MattWeth]

Looks like a 'hot rod' - very old school - takes the place of a primary coil in the cylinder by pushing water from the heating circuit through a long thin heat exchanger that fits in an immersion heater tapping. I've only ever seen one - I didn't think there would be any still about!

A modern indirect cylinder would be much more efficient. As it doesn't look like there's a motorised valve on it, you'd have to convert the pipework and controls to S or Y plan when you fit the new cylinder.

 

[diamondgas]

Hi Dan, where does the hot water supply from the diverter go to? I'm presuming a coil in the cylinder yeh? If the pipes are off the heating circuit and you also have a hot water circuit I'd do as you sugest and cut them back no longer required.

 

[PlumbBobBob]

the tom plumb did a video about these hot rod things a while ago

 

[dancinplumba]

thats a hot rod as matt says, and looks like a direct cylinder, if you are installing new indirect cylinder these two pipes need to go to heating coil in the side of cylinder, you can blank immersion boss or put in an immersion heater
imo

 

[Shower Engineer]

That takes me back haven't seen one of those for ages.

We used to use lots of these to convert a direct cylinder to indirect. They were common around the erly to mid 70's. Never heard them called a hot rod before, we called them by the brand name Microversion. I guess they were called that because they were made up using several lengths of 10mm tube. They worked very well but of course you lost the use of the immersion heater.

All you need to do as others have said is to connect the two pipes to the new inderect coil.

Hope that helps.

 

[tamz]

There were a few names for them. The microversion one as you say with the lengths of 10mm, Salamander i think made the hot rod version. There were a couple of others with the spring metal around the tubes and one with small fins on the tubes. We just called them a blade.
I think i may have a couple of different types lying around. If i remember, i'll post a pic for the un-initiated later.

 

[dan_the_plumber]

Haha.....Glad I started that thread, seams to of bought up fond memories of times gone by.

I however knew nothing of them untill asking an old bloke at city plumbing.

Yeah seams pretty simple now actually, just tee those two pipes into the flow and return into the coil of the new indirect cylinder

I'll prob just blank off the immersion heater then

Thanks all....Regards....Dan

 

[dancinplumba]

good scrap value in old cylinders much thicker than new ones, bonus !!!

 

[tamz]

More so if it is a riveted one :wink:

 

[tamz]

Before i forget


The first one was not a good version. One of the cheapies.
The second one is a Salamander version. It was actually called a hot tube. That one is brand new (20 years old at least) and still in the box.
Great the stuff you keep just in case :lol:

 

[Billy Bob Bob]

ripped out many cylinders with microversions they were a cheap way to convert a direct to indirect

 

[dan_the_plumber]

Aigh

 

[dan_the_plumber]

agh thats what they look like....Useful, Thanks