Wetback FAQ – advantages of North Solar systems over other evacuated “re-sellers”

I am looking at your NS300 hws and just have a couple of questions. I have installed a few of the **Brand** units and it looks like you are using a very similar tank/collector setup. Does your tank have any advantages/ differences over theirs?

Technology is the same however the configuration, engineering and material quality is different.
We design and manufacture our units with improvements in each run.
The quality of our materials is higher and the plumbing configuration is better. The lifespan of our units is longer and the plumbing quicker.

• From feedback, some other evacuated tube solar hot water resellers systems have a tendency of rattling when reaching high temperatures 90+ degrees
• North Solar systems don’t suffer this issue
• Plumbing of North Solar systems is designed to be simple and minimal, reducing installation time, cost, complexity and improving reliability
• North Solar frame is channeled aluminium giving it more strength and durability
• Wetback inputs are oversized (1 1/4”) allowing longer distances between wetback/system as well as permitting better capillary configurations for thermo-syphon properties
• Our systems are modular allowing addition of further non-pressurised solar collectors 
• North Solar provides accessories and parts for sale
• We stock extras including Sacrificial Anode Rods, Self regulated 12v circulating pump with dedicated 12v solar panels as well as installation kits
• We control the whole manufacture process for our systems

The header tank looks like a much better idea than the pv panel and solenoid. How does it cope with frost?

We tested the solar/solenoid configuration a few years ago and never implemented it in our systems as we found a high failure rate in the solenoids due to Australian conditions.
We regularly sell our header tanks to replace the solar/solenoid units.

No issue with frost. We have systems in Mansfield, Gisbourne, Lower Alpine regions of NSW.

Our design objective is for low/no no maintenance, we have supplied systems for 3 & 4 story townhouses and did not want to be going up there for repairs etc.

The the header tank consists of a float valve, insulation and standard BSP fittings, this configuration has proven very reliable with a long lifespan

And how much water would be lost as steam through the vent in the summer months?

The system will boil 4-6 times over summer, not necessarily on the hottest days but on days when the sun is ‘pumping’ the hardest. Normally the exhaust chimney will release steam for a few minutes (2-5mins) and may splutter some water from the header tank (100ml, if that). This is a normal process and most common on 35-45 degree angle – north facing installation. West and North West aren’t as prone, but do still occur.

We have engineered a fitting for the header tank to overcome the water splatter if it concerns you, it is available as an optional component. It is advisable to use this if you are using a non corrosive component in your wetback to avoid rainwater contamination.

From a loss of water scenario it is almost insignificant. I have a 300L test unit I have run for almost 18 months with no refill and it has lost perhaps 20mm-30mm.

And finally do you only have the one frame system or do you have one for steeper pitch roofs.

We have a 38 degree frame for a flat roof as well as a 22 degree frame for an angled roof. Your choice. We found that clients who want to be very specific in installation angles prefer to purchase the 38° frame and cut down the rear legs to have an exact angle requirement. We are happy to guide you in the process to achieve this if you have that need.

Looking forward to your reply, I am building my own house at the moment and will be running a wetback from the stove to hot water service. Your system is looking like it will do the job.

Yes, it is designed specifically with wet backs in mind.

We offer package discounts for install kits, anode rods and accessories for clients who purchase a full kit like the NS-300WB, NS-200WB or NS-SC20.

After Sale discounts also apply for replacement parts to North Solar clients in the need of parts further down the path.

$2299.99 – NS-300WB
http://northsolar.com.au/shop/index.php?rt=product/product&product_id=124

North Solar 300L wetback