DIY Projects - Compression fittings ( joints )

Compression joints are easier to use than capillary, but are more expensive. They are connected to the pipe by compressing a soft metal ring called an olive, this fills the gap between the fitting and the pipe creating a water tight joint.

Once you have cut the pipe to length, wipe the end of the pipe with a cloth to remove any surface dirt then make the joint.

	The compression joint consists of three parts, a body, olive and cap nut. Loosen the cap nut and slide the fitting onto the pipe, making sure the pipe has gone through the olive and reached the internal stop of the fitting. In most cases you do not need to fully dismantle the joint.
	If you need to dismantle the joint, slide the cap nut onto the pipe, then the olive and finally the body of the fitting. Make sure the pipe is pushed all the way to the internal stop of the fitting. Before fitting the olive check the sloping sides are of equal length, if not the side with the smallest slope should go towards the cap nut.
	Hand tighten the fitting then hold the body of the fitting with a wrench and tighten the cap nut with a spanner, to make a watertight joint the fitting needs to be tightened the correct amount to compress the olive onto the pipe, as a guide after hand tightening make one complete revolution of the cap nut with the spanner, to assist you mark the nut and body with a pencil line so you know when you have completed one revolution.
	To ensure you have a leak proof joint, once the fitting has been tightened, undo the fitting and wrap PTFE tape around the olive. Wrap approx. eight turns in a clockwise direction, this will stop it undoing as you tighten up the fitting.

DIY Projects - Soldered fittings ( joints )

Capillary joints are connected to the pipe using solder. There are two types of capillary joints, end feed is where solder is introduced to the end of the joint and capillary action sucks the solder into the fitting. Integral ring fittings come with the correct amount of solder in a ring to make perfect joints.

Selection of capillary joints

Once you have cut the pipe to length and cleaned the end of the pipe with wire wool as shown you can make the joint.

Take care when using a gas torch, especially in confined spaces such as under floors.

 

Soldered End Feed Fittings

	Apply the flame of the torch evenly over the joint until the flux begins to bubble.
	Once the flux has begun to bubble, touch the mouth of the joint in two or three places with the solder wire, until a ring of solder can be seen all the way around the joint. Allow the joint to cool for a couple of minutes before disturbing it.

 

Soldered Integral Ring Fittings ( Yorkshire Fittings )

	Flux is applied to the joints to prevent oxidization and provide a clean, grease free surface for the solder. Apply flux sparingly to the inside of the fittings and to the outside of the cleaned pipe, push the pipes up to the stop in the joint twisting them to make sure the flux is spread evenly.
	To protect the area behind the joint while using a gas torch, place a ceramic tile or plumbers fibreglass mat behind the joint. Apply the flame of the torch evenly over the joint until a bright ring of solder appears at each of the ends. Allow the joint to cool for a couple of minutes before disturbing it.

DIY Projects - Repair compression joints

Most leaks on compression fittings are caused by over or under tightening. To determine which it is, if there are any threads showing try tightening the cap nut half a revolution. If the fitting still leaks or there is no threads left, you will need to drain the pipe and dismantle the leaking side of the fitting.

Check the pipe goes right up to the internal stop, if it doesn't try pushing the pipe fully into the fitting. If the pipe is too short a new piece will need to be fitted.

If the olive looks OK then wrap about eight turns of PTFE tape around the olive and remake the joint. If the olive looks damaged or worn remove the olive and fit a new one. To remove the old olive, try turning and pulling the olive off by hand. If the olive is tight then try the following steps.

	To remove the old olive, place an open ended spanner below the nut and tap the spanner upwards, if you don't have the right size open ended spanner, you can use an adjustable spanner, but take care not to hit the thumbwheel as it will get damaged.
	If the olive is tight and will not tap off, carefully cut the olive with a junior hacksaw taking care not to damage the pipework. Cut diagonally across the olive as shown.
	Take care not to cut all the way through the olive, otherwise the pipework will get damaged. Cut until there is a slot about 3/4 of the depth of the olive.
	Insert a flat bladed screwdriver into the slot and twist. This should split the olive, if it doesn't, carefully cut the slot a little deeper but not all the way through and try again.
	Once the olive splits, it can be prised apart with the screwdriver and removed from the pipe. Clean any surface dirt off the end of the pipe with a cloth and make a new joint as shown

DIY Projects - Repair soldered joints

Leaks in soldered joints are mainly caused by dirt preventing a good joint originally, other causes could be poorly supported pipes causing stress to break the joint.

To repair a soldered joint requires the pipe to be drained of all water, it is usually possible to repair the joint by heating it with a gas torch and applying a liberal amount of self cleaning flux, quickly followed by solder. Both internal ring and end feed joints can be repaired using this method.

If the joint needs to be replaced and it is not possible to pull the connecting pipes apart, cut through the middle of the joint, this way the pipe lengths are not being shortened. Once the joint has been cut through heat up each end of the joint and remove. Clean the pipes by heating and wiping with a cloth then clean using wire wool.

Wear heat resistant gloves when handling hot pipes.