Whale water heater drain valve

My whale water heater [model:WH13O2. Capacity 13 Ltrs] manual drain valve is failing to close fully, resulting in a constant drip of water down the drain pipe to the ground. Loss of water turns the pump on after about 3 mins. I've opened and closed the drain valve many times with the pump on and off hoping the valve would close firmly but without success. I assume the valve could be partially blocked with lime deposits. So my first option will be to drain any remaining water from the heater tank and try again to fully close the valve. Second, to descale the tank/drain valve. Should have done this at the beginning of the season but thought I'd get away with it this year. I have a large 1 kg bag of citric acid which might do the trick. I will of course, as I have done before, follow the advice from other forum members on this forum on how to carry out this procedure. If all fails a new drain valve might be necessary. Any further advice from this forum will be appreciated.

Hi Mel

First off I would be inclined to remove the drain valve so you can manually inspect it, and descale it in the washing up bowl if necessary.

Only two screws if I recall, but the drain tube will be sikaflexed (or something like it) as it passes through the floor, so you will have to give it a good pull.

Apart from that you only need a strong thumbnail to release the hose fittings, and it should be a simple job.

Hope this helps.

Dave

Thank you Dave. Yes, your advice does help me. I did consider as one of my options of removing the drain valve to inspect/clean it but then got caught up with other long winded alternatives. The 'simple job' you refer to has convinced me to do it your way.