Noisy hot water system

Hi

I have a noisy Systemate 2000 and am hoping someone can confirm what is wrong.

The system was installed new in my first floor flat in about 2003. I recently had an issue with sludge - hot water wasn't moving around all the radiators, so that only the couple nearest the pumps were heating. I ran Fernox F3 through it and gave the system multiple flushes of water. For good measure I took both CH pumps apart and cleaned them (though by that point, save for some dried on sludge, they were pretty much clear). Heating seems all fine now.

In the mean time, over maybe the last 12-18 months, the system has been getting noisy (much more noticeably in the last 6 months). I thought it might be linked to the heating problem at first, but the noise is still there after I got rid of the sludge. I can hear the noise in the Systemate, but its much, much louder outside in the pipes. The noise occurs during hot water demand, and when the system fires periodically to maintain the water store. If the central heating kicks in the noise stops, and starts again when the central heating switches off.

Given the symptoms and what I've read about heat exchangers scaling up, I'm guessing that's the problem and that I need to get a plumber in to have it replaced. Thought I'd check to see if I'm missing anything though.

Many thanks.

Sim

Tricky. What sort of noise is it?

It's especially tricky as you say the noise occurs with HW demand, and when the boiler is firing to re-heat the store. These two functions share nothing with each other. No common parts, nothing! So I'm inclined to say you have two separate problems each making a similar noise. Issues like this on Systemates can be fiendishly awkward to fix so I'm inclined to recommend you cut your losses and replace it with something more sensible, like a MEGAflo.

Mike

Hi Mike

Thanks for coming back to me on this. I'd actually meant to post an update, so you've prompted me to do that!

It turns out it was something completely different after all. I must have been imagining hearing the noise from inside, as it was actually coming from a faulty one way valve on one of the pipes outside. Looks like it was worn down and rattling, the sound getting amplified through the pipes. My plumber replaced it and everything seems fine now. Still don't really understand why it was reacting in the way it was though!

I probably will replace the Systemate at some point, but I'm hoping I'll get a bit more out of it before I need to take that step. Will have a look at a MEGAflo then.

Cheers,
Sim

Excellent. Thanks fort the feedback!

The external non return valve is unnecessary anyway as there is an equivalent NRV inside the Systemate. These are prone to jamming open so I'd speculate someone fitted the external one to fix the problem caused by the jammed internal NRV. Either that or the original installer didn't realise the internal valve exists and fitted the external one as a result.

Mike