Solar Thermal From Scrap...AGAIN!

[dpmiller]

https://www.ebay.co.uk/itm/DC-12V-3M-Solar-Water-Pump-Circulation-Pump-Brushless-Motor-Hot-Cooling-New/263758894915?hash=item3d69415743:g:PqsAAOSwjodaJLB2

 

I'm using one of these on my solartwin stylee system. can vouch for their capabilities.

[Onoff]

9 hours ago, dpmiller said:

https://www.ebay.co.uk/itm/DC-12V-3M-Solar-Water-Pump-Circulation-Pump-Brushless-Motor-Hot-Cooling-New/263758894915?hash=item3d69415743:g:PqsAAOSwjodaJLB2

 

I'm using one of these on my solartwin stylee system. can vouch for their capabilities.

 

That looks like it'll do the job! What 12V panel do you use as in wattage? Cheers

Edited September 16, 2019 by Onoff

[Ed Davies]

1 hour ago, Onoff said:

Filled the panel with water from the hose and stuck one end of another short hose connected to the panel top right, in the hot tub hoping it would thermosyphon, sucking water up from the tub and pushing it out hot the other side. Nothing happened.

 

Was the panel manifold below the level of the water surface in the hot tub? Seems unlikely. If not a thermosyphon won't work.

[dpmiller]

I've a foot square panel that does about 10W, but have a 6v wallwart in parallel to ensure it starts in low-ish light. All through the solartwin differental controller

[Onoff]

19 minutes ago, Ed Davies said:

 

Was the panel manifold below the level of the water surface in the hot tub? Seems unlikely. If not a thermosyphon won't work.

 

No the panel inlet & outlet (same heights) were well above the tub water level.

[Gone West]

5 hours ago, Onoff said:

Anyone know where I can get a solar powered in-line pump with a small pv panel?

I've got a roof slate PV panel. Never been used that you can have to play around with if it's of any use. Output details:-

Pmpp 14.0W

Impp 4.89A

Vmpp 2.96V

Isc 5.07A Max

Voc 3.70V Max

[Onoff]

55 minutes ago, PeterStarck said:

I've got a roof slate PV panel. Never been used that you can have to play around with if it's of any use. Output details:-

Pmpp 14.0W

Impp 4.89A

Vmpp 2.96V

Isc 5.07A Max

Voc 3.70V Max

 

Thanks for the offer.....wouldn't be any good though would it to run the 12V pump direct?

[SteamyTea]

Following on from what @Ed Davies said about needing a height difference to get theromsyphoning going, and rather than having a largish tank of water above the panel or tubes, could one fit a heat exchanger above them.

Might even be possible to fit that in the loft and not use water as the transfer medium.

[Gone West]

1 hour ago, Onoff said:

wouldn't be any good though would it to run the 12V pump direct?

Sorry didn't realise you already had a pump.

[SteamyTea]

Could use that module to charge 10 cells and run the pump from that.

Or put a fat resistor on the wires and drop it direct into the hot tub.

[Jeremy Harris]

1 hour ago, Onoff said:

 

Thanks for the offer.....wouldn't be any good though would it to run the 12V pump direct?

 

 

Just connect it to a boost regulator.  One like this: https://www.ebay.co.uk/itm/MT3608-DC-DC-Voltage-Step-Up-Adjustable-Boost-Converter-Module-2A-in-UK-FAST/163769024236?hash=item262164feec:m:mUxc03WpRU3Xg2hZo256t8A would accept the variable voltage input from the panel and could be set to give a fixed 12 V out. 

 

 

[Onoff]

1 hour ago, JSHarris said:

 

 

Just connect it to a boost regulator.  One like this: https://www.ebay.co.uk/itm/MT3608-DC-DC-Voltage-Step-Up-Adjustable-Boost-Converter-Module-2A-in-UK-FAST/163769024236?hash=item262164feec:m:mUxc03WpRU3Xg2hZo256t8A would accept the variable voltage input from the panel and could be set to give a fixed 12 V out. 

 

 

 

Just the thing. Just been looking at DC to DC converters on ESR Electronics but this fits the bill much better.

[Onoff]

1 hour ago, PeterStarck said:

Sorry didn't realise you already had a pump.

 

I haven't got it as yet but have ordered the one @dpmiller linked.

 

It'd be nice to see you again but I'd probably do the cost of a panel off eBay in petrol!

 

If the car makes it...

[Gone West]

14 hours ago, Onoff said:

 

I haven't got it as yet but have ordered the one @dpmiller linked.

 

It'd be nice to see you again but I'd probably do the cost of a panel off eBay in petrol!

 

If the car makes it...

No problem. I was going to use the panel with one of these https://www.ebay.co.uk/itm/253475165592 and one of these https://www.ebay.co.uk/itm/233215849621 to power a water feature in the garden. I had an old slate water feature and drain gully which was to be the underground sump. I realised that it was a pointless waste of time and gave the various bits away on Freegle, which is where the panel will end up.

 

[Onoff]

22 minutes ago, PeterStarck said:

No problem. I was going to use the panel with one of these https://www.ebay.co.uk/itm/253475165592 and one of these https://www.ebay.co.uk/itm/233215849621 to power a water feature in the garden. I had an old slate water feature and drain gully which was to be the underground sump. I realised that it was a pointless waste of time and gave the various bits away on Freegle, which is where the panel will end up.

 

 

 

Bugger! So you actually had ALL bits I needed!

 

Would have been worth the trip. No doubt SWMBO and the youngest would have insisted on another trip to Wingham!

[SteamyTea]

1 hour ago, Onoff said:

Wingham

I went to school with a bloke that lived at Wingham Court.

Now if my memory serves me well, his name was.

Robert Conan Windham Lesley Maude.

There may, or may not, be initials, other than mister, before his name now.

[Onoff]

Holy thread resurrection!

 

A big thanks to @Marvinwho visited me yesterday, kindly bringing replacement evacuated tubes to replace my damaged ones. Top man. Had a nice chat too.

 

The plan is then x3 12 tube panels.

 

I've also just scored this tank, controller and pump combo. Bought off Gumtree (for £50) but in Edinburgh! Someone's gone and gotten and is holding it for me. Got a mate visiting rellies up there in July who can bring it back down South.

 

Just hope it works with these panels!

 

 

 

 

 

 

Next step is some scaffold up and strip off some tiles. I'm going to renew the felt under where the panels are going. Then stainless steel brackets and some Unistrut to affix the panels to. 

 

I need to find a couple of these roof pipe entries cheap or make something similar:

 

[Radian]

10 minutes ago, Onoff said:

I need to find a couple of these roof pipe entries cheap or make something similar:

Scrap copper HW tank & tin snips? 

[Onoff]

50 minutes ago, Radian said:

Scrap copper HW tank & tin snips? 

 

Copper would be maybe no good if you meant soldering to make watertight? Temperatures can get too high. More of an issue on the pipe joints I guess if a pressurised system where they can soften and burst.

[SteamyTea]

You got scaffolding?

My scaffold tower is currently in Bucks for the foreseeable. Pretty close to yours.

 

[Onoff]

9 minutes ago, SteamyTea said:

You got scaffolding?

My scaffold tower is currently in Bucks for the foreseeable. Pretty close to yours.

 

 

Think I'm sorted thanks.

[ProDave]

1 hour ago, Onoff said:

I've also just scored this tank, controller and pump combo. Bought off Gumtree (for £50)

That's not a "tank" but an expansion vessel.

[joe90]

35 minutes ago, Onoff said:

soldering to make watertight?

Silver soldering, brazing or compressions???

[Onoff]

4 minutes ago, ProDave said:

That's not a "tank" but an expansion vessel.

 

Sorry, that's what I meant. Thinking to invest in a decent big heat store. Options for heat sources etc.

[Onoff]

2 minutes ago, joe90 said:

Silver soldering, brazing or compressions???

 

It's all compressions on the panels I have here.