Options for replacing gas booster on solar hot water system

[snichols]

Hi all,

We have a Solarhart solar hot water system with a gas booster that's 10 years old. We have had a lot of problems with the gas booster failing over the years. Most of the parts have been replaced at some stage or another. The solar system works great. But the booster has now failed again so I'm wondering whether we should bite the bullet and replace it with something else. We had a quote a couple of years ago for a Bosch instantaneous unit to hook up to our existing solar tank as that plumber reckoned we would continue to have problems as the roof is a harsh environment for the booster - better to have a separate unit on the ground. But the reviews for the Bosch 21e are mostly terrible so I'm nervous. It was also very expensive - the quote was $2800 two years ago. Anyone got any suggestions about different options?

[Brad]

On the 2nd Solahart now since 1980, both had electric booster that apart from when I did early starts in winter has mostly been turned off, might not be a lot of help to you though.

[snichols]

Thanks Brad. Glad you've had no problems with yours. You must get more sunshine in winter than us. We really need the booster from this time of year onwards. 

I bit the bullet and got a Rheem 20 installed this morning. Couldn't put up with cold showers any more! The plumber says the Bosch I was originally quoted and the Rheem are both good but recommended the Rheem as its the same company as Solarhart and so warranty claims can be easier if there's ever a problem. I think its this one - https://www.bunnings.com.au/rheem-20l-natural-gas-60-c-continuous-flow-gas-hot-water-unit_p5103000 

I am surprised at how much installation costs. Took two plumbers about 3 hours to install, plus an electrician about an hour. 

[snichols]

Happy with the new system so far. Still smarting at the cost, but its good to have hot showers again! I'm also happy that there's not too much of a lag before the water is hot - which I had heard can be a problem with "instaneous" systems. Also hoping the gas bill will now be lower compared to the old booster which constantly kept the water in the solar hot water system tank on the roof hot rather than just heating water as needed. 

[krswarna]

Hi. I am having a similar issue. My gas booster has failed but solar unit is fine. I have a Chromagen unit. All the plumbers I contacted say they will decommission the solar heater. Did you also end up decommissioning it? Appreciate your reply.

[MitchellMc]

Welcome to the Bunnings Workshop community @krswarna. It's wonderful to have you join us, and many thanks for your question about solar heaters. 

This is a bit of an old discussion, but let me mention @snichols to see if they can provide an answer on their setup. @snichols went with an instantaneous/continuous hot water heater. I presume their existing solar tubes and system were decommissioned and removed or isolated from the new system. Were there any particular questions you had surrounding decommissioning an unused system? 

It might be a case where the replacement parts are not available to repair your current system. If you are unsure about what options are available to you, you should question the installer on why your system needs to be decommissioned.

Please let me know if you have any questions.

Mitchell

[snichols]

It wasn't decommissioned at the time @krswarna. It was run as a booster. So the Solarhart solar system warmed the water as much as possible, then the temp was boosted if necessary by the gas Rheem system. 

The problem with this set-up is we kept getting gunk in the Rheem as the Solarhart was aging. So last year we disconnected the Solarhart and removed it from the roof. 

I think a better bet is to have solar panels for electricity and an electric hot water system. 

[krswarna]

Thanks @snichols . Much appreciated. Even though I want to do my bit to be sustainable, looks like this is not an option and looks like I will have to decommission the solar unit anyway. 

[krswarna]

Thanks @MitchellMc . Would you recommend Dux instantaneous gas heater over Rinnai? Which one is better?

[EricL]

Hello @krswarna, 

It's great that you're considering using a gas heater. Gas heaters are considered continuous heaters. The heating element inside the gas heater takes a few seconds to reach operating temperature. The hot water will still need to travel the distance from the gas unit to the tap. So it will take a few moments before you get the hot water. But once it reaches its destination you'll get continuous hot water.

I've only ever used Dux, their reliability and aftermarket service is top-notch. You'll notice the gas heaters come in different sizes 17, 21, and 26. These numbers represent the number of litres of hot water it delivers per minute. The bigger the number the more taps it can service. So if someone is in the shower and the kitchen tap is turned on the gas heater will be able to cope with the added demand.

I recommend visiting your local store and asking about the installation of a continuous gas water heater. Dux is available in both LPG and Natural gas, so you can get the model that's most convenient to you. 

Here is a link to the Dux Brochure: Dux Water Heaters. 

If you have any other questions we can help with, please let us know.

Eric