What to check before putting a solar heater up

Most rooftop units use the thermosyphon effect. Sun heats the fluid in a flat collector, warm fluid rises by itself, and the tank sits above the collector so hot water collects where you can draw it.

That layout puts the weight up high. The unit needs a cold feed, and in a house with lock-offs that may come from a storage tank and pump, so ask how your supply affects the design. Many units also have an electric backup element, which is wiring work for an electrician.

Heavier than many people expect. These are makers' figures from outside Jamaica, not Jamaican data: one maker's manual from Rheem NZ gives full roof weight, and another from Solimpeks gives the full tank alone.

Rheem's advice is "If in doubt, consult a structural engineer". Our roof or ground page does the same sums for water tanks, which may be up there as well.

It can. One maker's manual says "In a scaling water supply calcium carbonate is deposited out of the water onto any hot metallic surface."

How hard your own water is remains an open question. We found no hardness data by parish or by National Water Commission system. The Water Resources Authority's 127.0 to 381.0 mg/L is a national ambient guide, not a measurement of anyone's tap.

So test your water, then ask the installer what scale does to this model and how it is cleaned out.

Yes, for tank life and for the warranty. One maker's manual, Solimpeks, says its tank is "protected against rusting with a large magnesium anode" but gives no replacement interval. Ask your installer.

Another maker's manual, from Rheem NZ, says chloride above 250 mg/L voids the stainless cylinder warranty. The Water Resources Authority uses the same figure as a sign of saline intrusion in groundwater, and names areas including the Hope River, Rio Cobre and Black River units.

If you are on a well or spring, test for chloride before buying.

There is a loan, and a duty break that may be over. The National Housing Trust's SMART Energy Loan offers "up to $2.5 million" (J$, undated page read 2 November 2026) and covers "Solar water heaters and solar insulation". It is for contributors, in a home the applicant "owns and occupies".

On duty, Jamaica Customs listed a CET suspension for "Solar Water Heating mounting accessories", which "commences on January 01, 2024 and ends on December 31, 2025". It covered accessories only. We did not check for a renewal, and could not confirm how GCT applies to these heaters.

We could not confirm a Bureau of Standards rule for solar water heaters. The nearest thing on the 2012 compulsory list is "JS 168: Construction and test of electric storage-tank water heaters", which covers electric storage heaters and may be out of date. If your solar unit has an electric element, ask whether it applies.

We also found no licence or register for solar installers or plumbers. So ask for the maker's manual before you pay, and check the full weight, the water limits and how it should be fixed down. More questions are on hiring a plumber.

That depends on how it was fixed, and we found no ODPEM wording on securing solar units. Ask the installer what the fixing is designed for, and get it in writing. Hurricane Melissa, on 28 October 2025, made landfall with "sustained winds of 185 mph".

Roof checks are for a paid, trained person on a dry, calm day, ideally early in the season. Wet weather or wind rules out any trip to the roof, and once a storm warning is out nobody climbs, whatever has come loose. The rest of the storm list is on before a hurricane.

It can, because on a hot, sunny day with little use, stored water can reach scalding temperatures. A tempering or mixing valve, fitted by the installer or a plumber, blends in cold water before it reaches the taps. We found no Jamaican temperature rule.

The relief valve is a safety device that lets out pressure and heat. Never cap it, plug it or block its drain line. If it drips a lot or runs steadily, have the installer check why, and do not try to stop it yourself.