On Wed, 08 Jun 2016 23:06:36 +0100, Capitol wrote:

F wrote:
On 08/06/2016 21:36, Chris Hogg wrote:
On Wed, 8 Jun 2016 21:21:16 +0100, F news@nowhere wrote:

On 08/06/2016 20:51, wrote:
On Wednesday, 8 June 2016 20:14:48 UTC+1, F wrote:
I'm looking to put our immersion heater on a timer. It's protected
by a
16 amp fuse so I assume the timer needs to be rated the same. Many of
the timers I've found so far seem to be 13 amp, even though some
claim
16 amp in the headline description.

Domestic immersion heaters are 3 kW maximum so a good quality 13
amp timer will be adequate.

The immersion heater must have a thermostat and all new ones should
have a secondary safety cutout with a manual reset. The thermostat
will be inside the cover of the immersion and usually slides into a
pocket so it can be replaced without draining down the cylinder.

Thanks.

The immersion heater in question is at least 38 years old and will boil
the tank if it's left on!

The immersion heater in my late mother's hot water tank has a
thermostat, and it dates from 1960. It may just be that your
thermostat was never set properly, or the setting has drifted over the
years.

I'll investigate once I've plucked up enough courage to disturb the
huge amount of 'stuff' in the cupboard!

Meanwhile, anyone got a recommendation for a digital timer? Or do I
use a spare I have that is rated 13 amps and which I use for switching
lighting when we're away?

I would need to replace the present immersion heater switch with a 13
amp socket and put a plug on the heater lead to plug it into the
timer. Any problems there?

Use a mechanical timer. IME digital timers are a pain.

I disagree completely. Mechanical timers make a noise and don't keep accurate time. Digital timers are silent and are as accurate as a digital watch. I can see no reason you'd have anything against a digital timer.

--
The only intuitive user interface is the nipple.