Is my Pulsacoil overheating?

I've recently bought a new flat that has a pulsacoil 2000 fitted in it.
I have my reservations about it and I'm suspicious that it has a fault (or, several faults)

After getting the system back on and up to temperature, the airing cupboard where it's located is getting very hot - given the efficiency claims this thing makes I would expect it would not be too hot around the unit. I've also noticed it makes a noise a bit like a kettle, so perhaps it's overheating (maybe some noise is normal though?) It does stop doing this regularly, suggesting that it's hitting a temperature and then stopping, but it goes off for less than a minute before heating again.

I don't think it's registering itself as overheating as I've heard that when this happens it cuts off until it's manually reset, which I haven't had to do

Looking at the circuit board LED, I get two blinks a second, suggesting normal operation, however neither the red nor green light on the front of the unit have ever come on (maybe the bulbs have just gone?)

Another thing I checked was the immersion heater resistances - one is at 18 ohms which sounds like it's right, but the other looks like an open circuit. I'm only measuring these values from the connector blocks on the front of the board though; perhaps I should try and get directly across the heaters?

On top of all this, we do not have a dual rate meter, so before I spend any money trying to fix the current set up, I'm wondering if it would be economically more sound to replace this system with a different one.

I appreciate I've talked about quite a bit of stuff here, but any opinions on any of the above issues would be welcomed.

Thanks for reading.

First thing to do is;
Read through the posts on here which will teach you lots.
Checked the water?
Checked the 2 rod stats?
Noise can be heaters and scale.
! or 2 litres of silencer would sort that out.
BUT
Get the unit sorted first.
Sounds like new heater and at least 1 new rod stat.
But check all for leaks etc.
All covered in the posts on these "things" / PC 2000.
Poor thing may not have been looked after properly!

Mike