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Noticed a drip on your Megaflo? Don’t call a plumber till you’ve read this…

If you notice water intermittently dripping through the ‘tundish’ (pictured right) on your Megaflo hot water cylinder. Don’t worry, this could just mean that the air gap inside the cylinder just needs reinstating, which is perfectly normal.

If after following these steps the problem still persists then call us, but you might be able to do this on your own and save yourself a call-out charge.

Here’s what you need to do…

Instructions on Reinstating the “air-gap” on a Megaflo:

The air volume within the MEGAFLO Eco unvented hot water cylinder will periodically require recharging to ensure any expanded water is accommodated within the unit. A discharge of water INTERMITTENTLY from the Pressure Relief Valve will indicate the air volume has reduced to a point where it can no longer accommodate the expansion. To recharge the air volume:

i) Turn off the heat source to the cylinder via programmers / immersion isolation switch(es).

ii) Turn off the water supply to the MEGAFLO Eco unit by turning off the isolating valve on the 3 bar Pressure Reducing Valve if fi tted at this point or at the 8 bar Pressure Relief Valve if fi tted there. Turn the blue handle so that it lies at 90º to the direction of fl ow (see Fig 6, p.13 for options on valve set) .

iii) Open the lowest hot tap supplied by the MEGAFLO Eco. Or even better, open many hot taps, this will allow air back into the cylinder quicker than only using one tap.

iv) Hold open the Temperature and Pressure Relief Valve until water ceases to run from the tap and

gurgling noise at the valve stops.

v) Close Temperature and Pressure Relief Valve.

vi) Turn on the isolating valve at the Cold Water Combination Valve by turning the blue handle so it lies parallel to the direction of fl ow, when water flows from the hot tap, close tap.

vii) The air volume will be automatically recharged as the unit refills. If after following the above actions water still discharges from the Pressure Relief Valve, for further advice give us a call. We’d be happy to help.

Megaflo unvented hot water cylinder Putney London

1 Comment

  1. Joe New on 20th October 2018 at 10:13 am

    Thank you, worked a treat in 2 minutes, saved me from panic meltdown as I had noticed knocking noises from pipework and prv gauge swinging 1-1.5 bar.

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