Merlett

Merlett pool hose couplers and PVC-U fittings

Flexible hose is what ties a pool circuit together. It runs from the skimmer to the pump, from the pump to the filter and back to the return inlets, and it absorbs the small misalignments that rigid pipework cannot. The weak point is almost never the hose itself but the joints at either end, which is why a sound coupler matters. Here you will find the blue PVC-U glue socket coupler in 38 mm, a straightforward way of making a permanent, leak-free connection on a 38 mm pool hose run.

What the range covers

The item listed on this page is the Merlett PVC-U glue socket in 38 mm, finished in the familiar pool blue that matches standard reinforced swimming pool hose. It is a bonded connection rather than a clamped one: the socket accepts the hose or pipe end, which is then fixed with an adhesive suitable for PVC-U. Once cured, the joint behaves as a single piece of material, with no clamp to loosen, no band to corrode and nothing protruding that could snag.

Couplers of this type are used in three main situations: joining two lengths of hose where a single run is not long enough, repairing a damaged section by cutting out the fault and bridging the gap, and adapting a hose run so it can be taken into a fitting, valve or union elsewhere in the circuit. The 38 mm size corresponds to the nominal dimension widely used on filter pumps, cartridge and sand filter systems and above-ground installations, so it is one of the sizes worth keeping to hand during a season.

Glue sockets and solvent welding in practice

A bonded PVC-U joint is only as good as the preparation. The general sequence is the same whatever the diameter:

• Cut square. A clean, perpendicular cut gives full contact inside the socket; an angled cut leaves a gap on one side.
• Deburr and clean. Remove swarf from the cut edge and wipe both surfaces free of dust, grease, sun cream and water.
• Dry fit first. Check the hose or pipe enters the socket to the correct depth before any adhesive is opened.
• Work quickly. Apply the adhesive evenly, push the parts fully home with a slight twist where the design allows, and hold them still for a few moments.
• Let it cure. Leave the joint undisturbed and unpressurised for the period stated on the adhesive container before restarting the pump.

Follow the instructions supplied with the adhesive you are using, and work in a ventilated spot. A bonded joint cannot be adjusted once it has set, so it pays to plan the geometry of the run before committing.

Getting the size and fit right

Pool hose is described in several ways, which is where ordering mistakes creep in. Before choosing a coupler, check the following:

• Measure, do not guess. Take the diameter of the hose or pipe end with a caliper or a tape across the widest point, and note whether that figure is the outside or the inside dimension.
• Nominal versus imperial. 38 mm sits alongside the one and a half inch designation used by many pump and filter manufacturers; 32 mm and 50 mm are the neighbouring sizes commonly found on domestic pools.
• Hose construction. Reinforced, spiral-wound and smooth-bore hoses behave differently when pushed into a socket, so confirm the end will seat cleanly.
• Both ends of the joint. Decide what the coupler has to meet — another hose length, a threaded adaptor, a union or a valve — and order the matching part at the same time.
• Access. Allow enough slack in the run to make the joint comfortably; bonded connections are difficult to assemble in a cramped pump housing.

Where these couplers sit in the circuit

Suction and return lines take the most handling over a pool season. Hoses are moved for winterising, pulled when a pump is swapped, and occasionally split by frost or by being trodden on. A glue socket is a tidy answer in all of those cases: the repair is low-profile, it will not vibrate loose, and the blue finish blends in with existing hose instead of standing out.

On the suction side a secure joint also protects pump performance, because air drawn in through a slack connection shows up as a noisy pump, a dropping pressure reading and poor filtration. Checking every joint when the system is recommissioned is a useful habit.

Merlett at PoolParthub.com

Here we stock the 38 mm blue PVC-U glue socket coupler, a small part that quietly keeps a pool circuit watertight. It is listed because it answers a specific, recurring need: joining or repairing 38 mm pool hose without relying on clamps.

Each listing shows the size and description so the diameter can be matched to what is already installed. If a run calls for a different diameter or a different style of connection, the wider selection of PVC-U fittings, unions, valves and hose on the site covers the rest of the circuit.