Water heater timer

[laserblazer]

In our consumer unit, there's a timer for controlling power to the solar heater. I meant to take a note of the details so I could google for instructions but I forgot. I think it's a Hegler. Anyone any knowledge of such things?

[RichardHenshall]

Might it be a Hager timer?

http://waterheatertimer.org/How-to-prog ... timer.html

[laserblazer]

Hi Richard,

Thanks, it is Hagar. there's one similar on the link you sent but ours also has a switch. I think it has been set to be on all of the time. I've turned it off completely for the time being.

[laserblazer]

OK, I've worked out how to set it, now when to set it. Presumably, the solar panel is going to keep the water pretty hot during the day, so if I put it on for an hour or two in the early morning and again early evening, then that should do?

[RichardHenshall]

I'm not an expert but would consider the following matters (amongst others?):

When do you use the hot water?
Do you need to ensure hot water at all times (ie for rental clients) or are you happy if it runs out?
How much do you use each day compared to the size of the storage tank?
Are you prepared to wait until it has run out before manually boosting it?
Are you on a bi-horário tariff?
How well does the hot tank retain the heat through the night if it isn't topped-up with electric heating?

The solar heating will be most efficient when the 'hot water' is cold, so the target scenario is to start the daily solar heating process with a cold tank, having already used the previous day's solar-heated water ideally without electric top-up. If it's sunny enough the following day the tank will probably re-heat from cold but if the tank was already hot in the morning as a result of electric heating then the sun can only top-up the electrically heated water (and replace what is used during the day).

BTW, if you need to search elsewhere for your particular timer's manual it is Hager (not Hagar), despite the consistent misspelling in the link I posted initially.

[laserblazer]

Thanks Richard,

We do need to make sure clients have hot water is needed. I don't know what it takes to run out of hot. Maybe a solution would be for the timer to kick in at say 4am for a couple of hours and then cycle 1 hour on 1 hour off until 11pm and then off overnight. Presumably, if the sun is doing its job, then a thermostat turns off the electric heater.