Slow running hot water

[VictorDelta]

I have a continuing problem with slow running hot water (all taps affected, gravity fed from a cold tank in the roof). We’ve never had the problem until the last few months and nothing has changed with our plumbing system.

Having read other threads on this subject, I assumed we must have an airlock and so used the kitchen mixer tap to push cold water back round the system. This improved matters for a day or two but then the problem returned. And now it happens virtually every day. The (gravity fed) cold water system works fine and I’ve checked that the hot water feed pipe is not blocked etc. in the cold tank.

Can anyone suggest what the problem might be please?

The only thing that has changed in the last year or two is that about 12 months ago we had a water softener installed (we live in a hard water area). Could some of the old limescale that had previously built up on the hot pipes now be coming loose and perhaps accumulating somewhere and so creating a blockage (which temporarily disperses when I do the mixer tap trick?)? Just a theory… (although I see no evidence of bits of limescale coming out of the hot taps).

 

[picasso]

there is a good chance that the bottom of your hot water cylinder is full of limescale, this slows down the flow through the cylinder, if you can remove the immersion heater and have a look.

 

[VictorDelta]

Thanks. Unfortunately, having a look isn't really an option at the moment.

If this were the case, is the only solution removing and cleaning the tank - or is there another way?

By the way, the cold in pipe seems to be 6" or so above the bottom of the tank...?