User-Programmable Timer


New Member
I did this project to control a water heater.

It has two schedules with two timing phases in each. A weekday schedule and weekend schedule can be programmed. The schedules are programmable by the end-user. The code can be altered to provide for individual schedules for each day of the week or year.

The timer can be adapted to control any load with the relay selection.

I hope to post the schematic and finish commenting the code shortly.
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New Member
Jon Henry,

I'd be very very curious to know how much this PICAXE based "programmable timer" project actually saves but not necessarily in dollars and cents. Having the water heater off for approx. half the day for a 5 day work week and periods over the weekend should save lots over a 2 or 3 month billing cycle? But that's just an assumption. Please post when you have some results. Not that I want to know how much your electric bill is, but possibly post a figure as a (%) percent in savings over a previous billing cycle. Cheers.

I don't actually pay for electric as I live in a company owned house in a small mining town in Outback Australia. But some day when I leave and face reality..... I'll have an electric bill.

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Michael 2727

Senior Member
HRA, I have one here (Bill) you can practice on if you like :)
Due to global warming, not much rain in our catchments VIC, OZ
and low Hydro Power outputs VIC Gov has to source Coal/Gas Fired
power from other states, and will increase our costs/charges by 13 to 18%.
I may have to invest in a timer myself :(


New Member
Michael 2727

Be glad its only 13% to 18%. In my area (Southern Louisiana,US) our electric bills have seen a 110% increase over the last 2 years. We have whats called the 'fuel surcharge' to thank for this. It is roughly 110% of the cost of the energy used that month. IE If the normal energy costs were $100 for 2200kwh, the fuel surcharge would be $110 bringing total costs for electricity that month to $210. Our normal rate is $.045/kwh and the fuel surcharge is $.0495/kwh.

The power companies justified this, with our states blessing, with the rise in fuel costs to run service vehicles.

This is what brought on the project.


I dont have actual numbers yet, that will take some time. I have done some research though. The average water heater in my area costs about $375 annually to operate. Given 2 full-heating operations a day (as opposed to the normal 'top-up' heating) and a 53% reduction in running time, my calculations say I should save about 40% of that annual cost saving about $150 annually. Costs to build the unit are about $70, so the unit in theory will pay for itself quickly.

Again these are calculations. I hope to report good news a couple months from now.
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