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Phil23
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Joined: 27/03/2016
Location: Australia
Posts: 1664

Posted: 10:46am 17 Jun 2016

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Bit of Graphical progress on my Spa Controller.
Code is still fairly basic,
Uses routines from Geoff's Park Assist.

Display output.

Options Menu, need to get rid of the Zero near other options.
Any suggestions?

Second Options Page.

Additional 3rd Page I added.

The Relay Board, 4 for 240V, 2 channels for 12V.

Control Logic needs to advance a bit.
It turned cloudy yesterday afternoon & the logic said stop pumping.
There was still significant solar energy available though.

Thinking a Panel Temp Sensor might be the next addition to address that.

Code contains the final version of the 1-Wire temp read Function.

That might be worth adding to a Library somewhere.

Now, What to do today....

Cheers

Phil.

Flow meter with DS18B20 installed below.

3 for the planned 4 Solar Panels.
Black Coro, 25mm Garden irrigation pipe & clear Polycarb on top.

Butchered Garden light to monitor solar levels.

The Heat Pump at various stages.

This needs to be moved to the roof...
The Cat's going to offer to help...

Valves to manually control water flow.
To be replaced with motorised ones once it get to that point.

Little Green valve to the left is important.
Provides a return restriction to create a head in the solar panels.
Use a couple of stand pipes for that.
Needs to be fully open for Heat Pump operation.
Another Motorised on will do that job.

centrex

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Joined: 13/11/2011
Location: Australia
Posts: 320

Posted: 11:46am 17 Jun 2016

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Very impressive Phil.
Do you have any form of pressure relief on the solar panels if the water flow stops for any reason they could get very hot.
All pumped solar systems monitor the panel temperature.

Keep it up always interesting reading your posts.

What part of AUS is this all happening in?Edited by centrex 2016-06-18

Cliff

Phil23
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Joined: 27/03/2016
Location: Australia
Posts: 1664

Posted: 12:47pm 17 Jun 2016

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centrex said
Do you have any form of pressure relief on the solar panels if the water flow stops for any reason they could get very hot.
[/quote]

I don't actually have any pressure relief. Did experience a lot of pipes popping off in the first weeks though, in the really hot months.

What I have done to resolve that is added 2 open PVC hoses as "Stand Pipes", on the inlet & outlet lines, up on the roof, and a restriction on the return line at ground level.
So the panel are only under the pressure of about a 1200mm water head.

They drain back when the pump stops.
About 35 litres, would probably be raising the Spa level by about 1cm.

That was necessary to overcome the issue of the siphoning effect I discovered.
The circulation rate was 7 litres/min, but siphon flow back rate was over 70 l/m, effectively making the pressure in the pipes 4 Psi below air pressure & causing the pipes to flatten when hot.

[Quote]All pumped solar systems monitor the panel temperature.[/quote]

Suspected that was the case.

Currently have 1 Temp sensor in the Tub (30cm depth), 1 monitoring water as it leaves (drawn from the very bottom), another reading it when it returns.
I also for Ambient Air (Doing nothing at this stage).

Was thinking of slipping another Temp sensor down inside one of the panels, under the polycarb, beside one of the pipes...

All my measurements & calculations told me I'd need 4 panels, a fact I never disputed, just added them one at a time, each month.

[quote]What part of AUS is this all happening in?

Northern NSW, about 100k's South of the boarder, 200k's North of Tamworth.

Ultimate aim is to have it usable 24/7 all year round with an affordable energy bill.
Something to do with "Happy Wife, Happy Life".

Cheers

Phil.

PS, intended on attaching the code to my OP, but forgot....

2016-06-17_224724_Spa_Controller_V1.01.zip

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