How to recharge the air gap on a Megaflo unvented cylinder

If you've noticed that water is dripping from the safety pipe outside or through the tundish on the outside of your cylinder, this is an indication that the air gap in your cylinder needs recharging.

This is a simple thing to do, and there are also instructions on a sticker on your cylinder.

1. Turn off the valve that allows water into your cylinder
2. Turn on the lowest hot tap in your home (probably the kitchen hot tap)
3. When the water stops flowing, go back to the cylinder and locate the temperature and pressure relief valve
4. Turn it gently anticlockwise and hold it. Water will start flowing through the tundish or hot tap. This is normal and means the air gap is being replenished within the cylinder.
5. When the water stops flowing wither through the tundish or hot tap and any gurgling noises stop, that indicates that all the air has been replaced in the cylinder. Let go of the temperature and pressure relief valve
6. Turn the valve back on that allows water into your cylinder
7. Turn the hot tap back off - be careful, as the water may splutter a bit!

Once you have finished carrying out this procedure, if the water is still dripping, either from the safety pipe outside or through the tundish, please call out your G3 qualified installer.

Please watch our video for a more detailed explanation of how to replenish the air gap.