Solar hot water heats water directly using collectors on the roof, stores it in a tank, and uses a booster to cover the shortfall when the sun has not done enough. RCM's own reviews include solar diagnostic work, and it is a system type we know well.
Roof orientation and shading vary enormously across the Sunshine Coast, from open coastal blocks to heavily treed hinterland properties, and that difference matters more to the outcome than the brand on the collectors.
This page carries no savings figures. The claims on our current site quote annual savings and emissions reductions without stating the system, the household, the energy price or the date, and the brief for this rebuild is explicit that those should not be carried over. What follows instead is the set of things that genuinely determine whether solar works at your place.
How the system is put together
Collectors on the roof absorb solar radiation and transfer that heat to water or to a heat-transfer fluid.
A tank stores the result. On a close-coupled system the tank sits on the roof directly above the collectors and circulation happens by convection, with no pump. On a split system the tank is at ground level and a pump moves fluid between the two.
A controller decides when to circulate and when to boost. A booster, electric or gas, makes up the difference.
Roof-mounted tanks put considerable weight up high, which is a structural consideration on some roofs and one reason split systems are common.
Orientation, tilt and shading
Government guidance notes that collector orientation, tilt and shading all affect how a solar system performs. On the Sunshine Coast, a north-facing roof at a reasonable pitch with clear sky through the middle of the day is the best case.
Shading is the factor most often underestimated, partly because it changes. A tree that was small when the system went in shades the collectors five years later, and the only symptom is a higher bill, because the booster covers the gap silently.
None of this makes a compromised roof unusable. It changes how much of the work the booster does, which changes the economics, which is exactly what you want to know before committing rather than after.
Boosting, and why it decides the running cost
Every solar hot water system has a booster, because no household accepts cold showers after four overcast days.
How hard it works is the single largest factor in what the system costs to run, and it is invisible: a solar system whose collectors, pump or controller have stopped contributing still delivers hot water, because the booster takes over. Plenty of people run an expensive electric water heater with panels on the roof for a year without knowing.
That is the strongest practical argument for having a solar system checked periodically. The failure mode is a bill, not a cold shower.
Repairs: pumps, controllers, collectors and boosters
Circulation pumps and controllers are the two most common failures, and both produce the silent symptom described above.
Collector damage happens: hail, falling branches, and in a coastal climate, corrosion at fittings and flashings over time.
Booster elements fail like any other element. On a system where the booster has been carrying more load than it should, they fail sooner.
The good news on repairs is that the expensive parts, the collectors and the tank, are usually the ones that survive. Most solar faults are components on an otherwise sound system, which makes them worth repairing.
Solar or heat pump
Both reduce the electricity used for hot water, by different routes. Solar collects heat directly and needs a suitable roof. A heat pump moves heat from the air and needs suitable outdoor space and tolerance for some noise.
Where the roof is right, solar is a genuinely direct approach. Where it is not, a heat pump often achieves more, particularly paired with solar power.
The comparison page sets both out side by side against the factors that decide it.
Richard (RCM Hot Water) was superb in his tenacious problem-solving in which the solution was far from obvious and ultimately required ruling-out several potential problems to restore our solar hot water system to full working order. I would most definitely use his cheerful services again... and again...
These are reproduced from RCM’s Google reviews with the names as published. This is a selection rather than the full set. Read them all on Google
There is no honest single answer, which is why we do not publish one. How much of your hot water comes from the sun rather than the booster depends on your roof orientation, its tilt, what shades it through the day, your household's usage pattern and the system itself. The same system on two roofs in one suburb can perform quite differently.
Is solar hot water the same as solar power?
No, and they are easy to confuse. Solar hot water uses roof-mounted collectors to heat water directly, with its own tank, pump and controller. Solar power generates electricity for the whole house. You can have either or both, and a heat pump paired with solar power is a third approach that achieves something similar by a different route.
What if my roof faces the wrong way?
Orientation, tilt and shading all change how much the collectors contribute. A poorly oriented or shaded roof does not make solar impossible, but it does mean the booster does more of the work, which changes the running cost and therefore the case for installing it. It is worth assessing honestly before committing rather than afterwards.
What is the booster for?
It covers the gap when the sun has not delivered enough, using either electricity or gas. Every solar hot water system has one, because nobody accepts cold showers after a run of overcast days. How hard it works is the single biggest factor in what the system actually costs to run.
What goes wrong with solar systems?
Most commonly the circulation pump or the controller, and both have a particular character: the system keeps producing hot water because the booster quietly takes over, so the fault can run for months before anyone notices the bill. Collector damage and booster element failure are the other regulars.
Can solar hot water create certificates?
Eligible solar water heater models can create Small-scale Technology Certificates, on the same terms as heat pumps: eligibility is specific to the model, checked against the current official register, and there is a period within which certificates must be created. Get the exact model number onto your quote so you can check it yourself.
RCM works across Sunshine Coast and the hinterland. See the full Sunshine Coast service area for where we work regularly and where we travel on different terms.
