How to improve my roof top solar hot water system with gas booster?

Bindu1

Hi,

We do have Solar hot water system (tank is installed at the rooftop) with a gas booster which is more than 10 years old. Recently noticed a water leak from the roof top water pipe connected to the tank. It is a 270 litre Edward solar system with a  Rheem  integrity 20 lit/m gas booster connected to it. The gas pipe is 20 mm and the water line is 15 mm. We are not getting enough hot water, if we use 2 hot water taps or shower simultaneously. 

1. If I disconnect the solar system at the roof and replace the Rheem 20 lit with a Rheem 26 lit will solve the issue?

2. I have approached a trade person (a licenced plumber), suggested, he only can replace with the same 20 lit Rheem instantaneous in the system, as the gas line to not big enough for 26 lit. Again he said even he install a 26 lit , there wont be sufficient hot water if 2 taps or shower open simultaneously. Also to Isolate the existing solar tank & water connection and let the new instantaneous system to work, he need to replace new valve kit (for the same 20 li Rheem Gas system), the one I have replaced an year before. Said this new valve is required as this  independent from solar.

My questions are as follows

- Why can't they install a 26 lit instantaneous hot water system to my house?

- Why if they are installing the same Rheem 20 lit unit needed a new control valve installation?

- Other than water leaking at the roof tank, my hot water system working okay (one tap or shower at a time to get sufficient hot water). Is that okay, if I have get the roof top solar tank and panels isolated and dismantled and let the 20 lit Rheem booster, without changing the existing valve (tampering valve) controls?

Highly appreciated the answers..

Regards

Bindu

MitchellMc

Welcome to the Bunnings Workshop community @Bindu1. It's wonderful to have you join us, and many thanks for your question about hot water heaters.

Those sound like great questions to ask the plumber, as without knowing what influenced their recommendation, we could only assume they are correct. Perhaps you might like to get a quote from another installer to check that the information you were provided with is correct.

A 26L/min continuous flow hot water heater would typically be enough to run two hot water taps simultaneously. However, it is not just about how much water the unit can heat but also flow rates. If two outlets consume 9L/min each, but the 15mm water line can't deliver that much, then that's just as bad as a hot water unit that can't heat the water fast enough. So, in answer to your questions, although the 26/L unit has a higher capacity, it still might not solve your issue.

I'd recommend you either ask these questions of the installer or verify with another one. 

Please let me know if you have any questions.

Mitchell