Telford Indirect 135L Combination Cylinder Backing Up

[Daniel Howden]

When the immersion heater is on I get some backing up in the cylinder - the hot water pushes up to the cold section of the tank. Is this a normal thing, as in the hot water will expand and rise or do I have a problem?

I did adjust the ball valve so there is less cold in the top section giving room for the hot water when it flows through.

Thanks, Daniel.

 

[townfanjon]

Yes it will expand a small amount , as long as the header tank has enough water in it to top up the cylinder its ok .

 

[John.g]

There must at least 10/15 litres of cold water below the immersion element level so say 125 litres of cold water heated to 60C would expand ~ 2 litres back through the cold feed and as this water is cold/lukewarm in the bottom of the HW cylinder then you would think that it would hardly be noticeable in the cold feed tank above it except that this cold feed tank has a very small capacity. I would just check that the immersion is cutting out at its set point and check that no hot water is coming out of the vent pipe.