Solar Hot Water systems from Ebay, anyone have experience with them?

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Solar Hot Water systems from Ebay, anyone have experience with them?

(13 posts) (5 voices)

Started 11 months ago by mick_queensland
Latest reply from mick_queensland

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solar hot water

mick_queensland
Member

Hi All,

I am looking for a solar Hot Water System to replace my electric HWS. I have had a lot of quotes from many different companies on various types of systems. Each has their pros and cons, but I must say that the cost seems to be rather high for what you get.

Then I had a look on EBAY at the systems there (easy to find them, just search for "Solar Hot Water System" and there they are for around $1300 excluding delivery of course. Of course these systems do not garner the Government rebates so you pay that and that's it.

Oddly, and I am not certain, it seems these systems have many of the pros and few of the cons of the other systems. Firstly, then have no pumps or controllers, which is a big bonus, just look at the posts on this forum for examples. Secondly, since the water is heated via heat exchanger you don't need to worry about bacteria growing in low temperature water. Thirdly, since the system is not mains pressurised you don't need to worry about airlocks, problems with cracking welds and leaking joints is reduced, and no water overflow every day from overheating manifolds. Fourth, installation is simplified, allowing most of the system to be installed yourself, and the final connection can be done by your plumber and sparky.
The main con is the weight on the system on your roof (same con as any other tank on the roof system) The other con is what quality of Stainless Steel is used in the construction of the tank.

So, the question is, has anyone got one? If you do how is its performance?

Cheers, Mick

Posted Sunday 29 May 2011 @ 5:17:06 am from IP #
sun2steam
Member

Mick,
I agree with you.
The only additional potential negatives I can see are:
a) Safety. When a glass tube breaks, the whole tank content may rush out, overflowing the gutter and potentially hurting somebody standing underneath. risk=low; potential of damage=high
b) as with any heat exchanger system, the temperature will depend on the flow rate.
c) make sure you pick up the system or that the supplier carries the risk of transport.
d) ask for a spare tube in case something goes wrong.

Use lubricant (dish washing liquid is good) for easy installation of the tubes.

Posted Sunday 29 May 2011 @ 8:09:00 am from IP #
amun-ra
Member

mick remember cyclone rated system tie down for your area you will have to have it enginered to comply (apricus does) no mains pressure means gravity feed or pressure pump to your house =extra cost or the waf wont be very high, keep looking sure you will find
a suitable system soon mick

Posted Sunday 29 May 2011 @ 12:13:08 pm from IP #
mick_queensland
Member

Hi guys,

@ sun2steam: The system tank is sealed and the Evac Tubes plug into it like any other ET manifold. So, if a ET breaks there can be no leak from the tank, just like other ET systems. Yes there are welds here but they are only under the pressure of the tank water, not Mains. Agree with your other points though. You would have to pay for insurance on the transport.

@ amun-ra: I did note the frames are quite flimsy. That's fine for down south but as you say, up here I need something substantial. I questioned this with one of the suppliers by email and their reply was to call their Rep in Melbourne for advice. I haven't done that (yet) Still, it would not take a lot to mount the system up to Cat 4 or even Cat 5 and it could be done yourself if you are a handyman.
The hot water is mains pressure, it flows through a heat exchanger copper tube inside the stainless tank on the roof.
Yes, the WAF.... well she seems to be coming around and now sees that soon it is going to be common to see these types of installations. It has taken nearly 12 months for her to start to change her mind on the aesthetics though. Personally, I wouldn't mind a nice shiny stainless tank and some glittery tubes on the roof. Yes the search goes on.

Back to my main points:
Has anyone used one of these systems?
The cost of "approved" systems seems inordinately high to me, comments?

Cheers, Mick

Posted Sunday 29 May 2011 @ 11:24:11 pm from IP #
sun2steam
Member

Mick,
I wanted to go through the certification process, but I gave up as the total cost was around $50000. No wonder the very few companies with approval are using their oligopoly to get good prices.

Without this nonsensical extra certification to Australian standards for systems that already have all European and sometimes US certification the system price could be about half.

About safety. There are various systems. If the system does not have heat pipes but heat exchangers, it is most likely a direct contact system, meaning the glass tubes are filled with water and the tank is not sealed. Maybe you can show a link.

Posted Monday 30 May 2011 @ 12:25:59 am from IP #
mick_queensland
Member

Hi sun2steam,

have a look at this one as an example, it is not the only one there that works on this principle. http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=110691733919&fromMakeTrack=true

See what you think.
cheers, Mick

Posted Monday 30 May 2011 @ 12:58:41 am from IP #
mick_queensland
Member

Here is another one, this one has some good pics and diagrams. Note than none of them provide any real data though. I have requested some info from them.

http://www.ebay.com.au/itm/30-Tube-Solar-Hot-Water-System-250L-vacuum-tubes-/260669336844?pt=AU_HotWaterSystems&hash=item3cb11a6d0c

Posted Monday 30 May 2011 @ 1:02:18 am from IP #
sun2steam
Member

OK, that is what I thought. These systems have hot water in the tank AND in the glass tubes. If one glass tube breaks, the whole tank will run empty. No a major disaster if you make sure that nobody will be hurt.

Posted Monday 30 May 2011 @ 1:38:56 am from IP #
franks
Member

With STCs/RECS tanking in price, you can pick up a solar retro kit for a electric HWS
can get a kit on eBay for $1200-1400, im looking at converting a HWS tank to Solar, heaps cheapoer than get a approved system+install ect to get back $1000 in rebates, your still payed $2500+ for approved Solar HWS.

Posted Monday 30 May 2011 @ 1:50:01 am from IP #
mick_queensland
Member

Hi sun2steam,

interesting, I did not ask that question about the tubes. I assumed that they were standard ETs and fitted into sleeves in the tank. I am still trying to find the link where I saw the system I am thinking of, but it could be a mains pressure tank.
Anyway, how did you find out about the tubes being filled with water?

@ franks: got a link to that, I dont see a retro fit kit. I agree that the approval process is not the best system as it keeps out the small players & lower end of the market, which reduces innovation. The approval process does however mean that if you buy an approved system it will work and last for a minimum time (provided it is installed correctly)

Cheers, Mick

Posted Monday 30 May 2011 @ 2:50:10 am from IP #
sun2steam
Member

Mick it was simple, I did sell some.

Posted Monday 30 May 2011 @ 3:50:49 am from IP #
Ueee
Member

Mick,
Try FX Larkin for retro kits, although its a long way to freight for you. You could also try run on sun, they are further north but are a bit more expensive. I decided to build flat plate collectors and put them on my NW wall so overheating won't be a problem in summer. Am still finishing them i'll let you know how it goes. I picked up a 150l stainless tank today for extra storage-cost? free its amazing what people will throw away, its a gas unit only 4 years old- the people replaced it with a Rinnai Infinity and threw the old tank to the curb.

Posted Monday 30 May 2011 @ 11:04:36 am from IP #
mick_queensland
Member

Hi Guys,

just thought I would freshen up the thread a bit with the latest on my hunt.
After a chat with a solar installer, I contacted the engineers that did the specs for my house and it will cost at least $300 for a structural certificate for a tank on the roof system, plus whatever extra work is needed too. The engineer I spoke too seemed to think that even though north queensland houses are super strong, there would be more bracing needed. Hmmmm
So, back to a split system.....
Cheers
Mick

Posted Thursday 21 Jul 2011 @ 7:41:20 am from IP #

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