Gas Hot water system

gav89z · Apr 22, 2014 7:28 pm

Hi all,

Just looking into the Gas hot water systems, either can go into Continuous flow or Gas Storage i.e. Rheem Stellar http://www.rheem.com.au/Products/domestic/gas/mainspressurestorage/stellarreggas/rheemstellargasstoragewaterheater330360

Any thoughts? I went into Hardware General store in Sydney and the rep recommended Gas Storage Rheem Stellar over continuous flow, or recommended to install 2 x continuous flow units, one 26L and one smaller one i.e 20L for kitchen/laundry/powder room downstairs, to ensure enough supply of "hot" water...

Thanks!

bpratt · Apr 22, 2014 8:28 pm

If you go for gas storage, then I reckon you should be looking at solar hot water, that just uses the gas to boost if the tank isn't up to temperature.

Evacuated Tubes are the better type of solar hot water, particulary the further south you go, but flat plate solar is okay too.

grumblebum54 · Apr 23, 2014 4:14 pm

We installed a Rinnai Infinity 26 when we built in 2005 and hated it. In the bathroom towards the back of the house the shower always went cold even though we had the water controllers set at a reasonable temperature.

The temp in the unit was set at 50 degrees so when you had greasy washing up or wanted to wash the tiled floor you had to boil the kettle heaps of times to get enough really hot water.

I suppose the units are better nowadays but in our second build in 2011 I wasn’t prepared to take the risk and we have a Rheem Stellar storage heater, no solar and our last quarterly bill was $118 so quite happy with the product.

I think when you install gas boosted solar the booster is an instantaneous one.

gav89z · Apr 23, 2014 9:05 pm

Thanks all,

Just a quick one any feedback on this?

http://ledaaustralia.com.au/products/continuous-gas-hot-water/

6 star efficiency 26 capacity and around $280 cheaper than a Rheem 26, looking to get two installed so save around $560 over two units.

gav89z · Apr 24, 2014 6:56 pm

Looked at Rheem 27 unit 6 star efficiency $1000

Stewie D · May 12, 2014 12:11 pm

We have an older Rinnai Infinity 26 that was installed about twelve years ago and it is a great unit.
One thing they do need though is good plumbing between the unit and end tap. Most of our plumbing has been run in 20mm copper down to a minimal amount of 12mm and all the taps that come off that have piping hot water coming out. The only one that doesn't is our shower which has 2m of 12mm copper plus a flow restrictive shower head which is why sometimes the water goes cold. It is probably a combo of the pipe size and the shower head that is causing this.
I read somewhere that they need a minimum of 2L per minute to maintain the hot water level.
Some other facts from the Rinnai FAQ...
There are several possible solutions to minimum flow rate issues: lowering the temperature on the unit to a more comfortable temperature to avoid cutting in too much cold water; cleaning the inlet water filter on the cold water inlet of the unit (sediment buildup in the filter can decrease flow into the unit); cleaning or removing the aerators from showerheads or fixtures; or replacing low-flow showerheads or fixtures.

When you use the shower the water flowing through the Rinnai is usually quite low so the machine will switch between high and low flame to maintain the required temperature. If the low flame pressure has not been set correctly, the low flame may be too hot for the water flowing through and so the rinnai will have no choice but to shut the burner off momentarily or longer to prevent overheating. This is where the shower goes cool for a few seconds or a few minutes. Ask your installer to check the burner setting on low. This involves using a digital manometer and selecting the appropriate jumper switch on the PCB. Full instructions should be on the inside of the rinnai front cover...

Stewie

sceen7 · May 12, 2014 2:28 pm

We have had a Rinnai enviro 26 for over 2 years now and love it. We have controllers in the bathrooms set between 28 and 43 summer winter. We have water saving shower heads and have never had a problem with the unit switching off. Best of all it is astonishingly efficient. In summer our gas bill is a pleasant surprise rather than a shock. Don't be put off by a slightly higher price, it has paid off the extra bucks in just one year.