How do you fix a roller shutter that won't open?

Find out which of four things has failed, because each has its own fix and only one of them means taking the shutter out. In a Portuguese roller shutter, the estore de rolo in its caixa de estores above the window, a shutter that will not go up has a snapped strap, a winder with no tension, slats jammed or out of the guide, or a worn bearing or bracket on the shaft.

Which of the four faults is it?

• Snapped strap. It comes away in your hand, vanishes into the slot in the wall, or hangs slack and pulls nothing. The commonest fault by far: the webbing wears where it folds over the reel in the winder.
• Winder with no tension. The strap is whole but goes slack when you let go, or the shutter rises partway and stops with the strap hanging. The spring in the winder is tired or broken.
• Slats jammed or out of the guide. Resistance partway up, a scrape from one side, the curtain climbing on a diagonal. Sand, salt and old paint in the guides, or a slat that jumped when the shutter was forced.
• Worn bearing or bracket. A constant squeal on the way up, the curtain dropping to one side, and with the lid off, a shaft that is not level.

The safety rule before the lid comes off

Put the shutter fully down first, so the curtain’s weight rests on the sill and not on the shaft, and nothing can drop when the strap or the shaft is released. If the strap has already gone and the shutter is stuck up or partway, clamp the curtain in its guides before touching anything inside: a clamp on the bottom rail against each guide, or a wooden wedge in each channel. A large aluminium curtain is heavy, and one that lets go inside the box breaks slats and hurts hands. On an electric shutter, switch the circuit off at the board first.

The lid is on the room side, on two or four screws, often under plastic caps. Old lids are heavy and carry years of dust and sometimes a nest, so support the lid as the last screw comes out, and cut the seam of a lid painted shut rather than levering it.

How do you replace the strap?

1. Shutter down, lid off. Clear enough dust to see the shaft, the drum the strap winds on, and the slot down through the wall.
2. Take out the rest of the old strap, from the drum and from the winder. The winder comes out on two screws; the reel inside is spring loaded, so let it unwind slowly in your hand.
3. Measure the new strap: twice the height of the window plus about a metre, in the same width as the old one, 14 mm or 22 mm.
4. Feed it from the box down through the slot to the winder opening, taped to a stiff wire on a long hidden run.
5. Fix the end to the drum and turn the shaft by hand until the strap lies flat and has taken several turns. With the shutter down, most of the strap sits on the drum.
6. Give the winder its tension before hooking the strap on: a few turns of the reel against the spring, then hook the end and refit it, leaving the reel enough travel to take in all the strap on the way up.
7. Test with the lid off, up and down twice, and only then close the box.

The tension mistake

Too many turns on the reel and it binds before the shutter is fully up: the shutter stops short, and every pull after that drags the new strap against a reel that will not give, which wears through it in months. Too few and the strap hangs slack when the shutter is up and kinks in the slot. If the shutter stops before the top on test, unhook the strap and redo the turns with fewer. A winder whose spring has failed on its own is replaced, not rewound; a new one fits the same recess on the same two screws.

A slat out of the guide

Do not force it. Look at which side of the curtain has climbed: one slat has jumped its channel and locked the curtain on a diagonal. With the strap slack, ease the high side down until the slat drops back into its channel, lower the shutter fully, and clean the guides: brush out sand and flaking paint, rinse with fresh water near the coast, and never grease, which holds grit. If a slat is cracked or the bottom rail is bent, read on.

Where the DIY stops

Replacing a slat means dropping the whole curtain: unhooking it from the shaft, taking its weight, sliding the slats out sideways down to the damaged one, fitting the new one in the same profile, and rebuilding. It is a two-person job, and on an upper floor it is done at an open window with the weight in your hands. Several cracked or warped slats, or a bent guide, change the arithmetic: a whole new curtain is usually cheaper and runs better than slats replaced one at a time.

If that is the job in front of you, or a strap change is not how you want to spend a Saturday, shutter repair in the Algarve covers what the visit includes and how it is quoted from a photo of the open box. If the real question is whether an old shutter is worth repairing at all, is it worth repairing an old shutter sets out the rule of thumb.

What if it is an electric shutter?

Do not open the motor: it is a sealed tubular unit inside the shaft, at mains voltage, with nothing a homeowner can service. Check the breaker, the wall switch and the remote’s battery, then wait a quarter of an hour in case the thermal protection has tripped after repeated use on a hot afternoon. A motor that stops a hand short of the top has lost a limit setting, and its manual describes the adjustment.

If the motor has a manual override, a crank eye at one end of the box turned with a detachable handle, that is how the shutter goes up without power; if not, leave the curtain alone, because the gearbox holds it locked and pulling on the slats breaks the hooks at the top. A motor that does nothing at all, no hum, with power at the switch, is a motor or capacitor job, at mains and with the shaft out of the box, which is why a professional does it.

Use the box while it is open

Three things while the lid is off. Clean it out. Check the top of each guide where it meets the box, for play and for a missing end stop. And look for insulation: in many Portuguese houses the box is a bare void with a slot to the outside, the coldest, draughtiest point of the window. A board of rigid insulation, cut to leave the rolled curtain room to turn, and a brush seal along the slot are a small job with the lid already off.