The CORRECTED tank indicator project

Rodney Baxter

THIS HAS NOW BEEN CORRECTED
I am a student a Dundee University studying mechanical engineering and would like your help with one of my projects.

Most cylinder tanks for heating domestic water are kept in an inaccessible area such as the hotpress / airing cupboard. A person however does not know how much hot water is actually in the cylinder without being there to touch it. It would be inefficient for the tank to be full of hot water all the time and therefore it would be useful to have an indication of the hot contents in an accessible place such as the kitchen. Also there must be enough water for daily events.

My project is to propose a method of indicating to the householder/user remotely, the state of the hot tank contents eg.some sort of scale / reading device. Sketchs must also be shown where appropriate.

Please could you give me any information what so ever on this project or any simple solutions to this.

Your help is much appreicated

Rodney Baxter

John@Reliable

Rodney, I found it!
Check out National Magnetic Sensors @ Nationalmagnetic.com
this should help you. Good Luck

Dale

Interesting topic, some ideas to ponder

I was asked for something like this once by a Friend in the Canary Islands town near Las Palmas. Water cistern on the roof only filled a few times a week. Wanted to know how much was in the roof tank from the kitchen, Float with variable resistor was on thought, ended up using a Pressure transducer on a tee in the bottom drain that gave milliamps and then coverted to depth of water since it was a gravity system. To know how much water you could run a small nylon sensing tube to another room to a transducer or diaphragm switch. If you want to know how much HOT water is in the tank not just how much water I would think thermocouples along the tank wall should work, could set up a transistor switching or Zeiner diode knee that would light a vertical column or lights if the water under that thermocouple was hot enough. Stay with your education, we need the help.

Aidan (UK)

The 'cylinder tank for heating domestic water' (indirect water heater) will ALWAYS be full of water. The cold feed (from the storage tank in the loft) enters at the bottom of the cylinder and the hot water comes out the top. If the mains water fails and the storage tank is run dry, the cylinder will still be full of water. You can't empty it through the taps.

The only variables will be;

1) the temperature of the water in the cylinder, and

2) the water level in the cold water storage tank.

That's the way it works. You need to study that diagram, Rodney.

So, are we talking about a temperature indicator for the cylinder, or a level indicator for the cold water storage tank?

Rich

Corrected

O.K. Rodney you have made some corrections. Let me suggest something that I had done a few years back that worked wonderfully. It is so simple and maintenance free that you may not catch on... so bare with me. A company called fluidmaster makes a level control that is made out of plastic. Yes, it is used on toilet tanks in the USA, but it is still a level control. This "ballcock", is very sleek. Will fit in a 6 inch or possibly a 4 inch inside diameter pipe.The pipe can be installed on to your tank remotely. The Fluidmaster ballcock can then be installed inside the piping.The water level can be adjusted at the ballcock.You can draw off water and have water refilled at the ballcock at what ever level you desire depending on your piping arrangement. I did this at a old manufacturing plant using a Fluidmaster 400A ballcock.It worked great.Try it! It works. Go to www.fluidmaster.com. and best of luck to you.

Aidan (UK)

P.S.



I should explain that the pipework is designed like this
(so that the indirect water heater cylinder cannot be emptied) because the cylinders can be fitted with a secondary electric resistance heater, fitted in the top. This is similar to the heating element in an electric kettle. It would wreck the heating element if it were used without being immersed in water.