New mixer needed?

Hi,

Firstly can I say thank you to Mike for a really informative and helpful website.

I have been having problems with the hot water from my pulsacoil (not sure which model, but it is about 15 years old) over the last few days the water has only been getting mildly warm, never hot. I am not experiencing any loss of pressure. Had an engineer around today who told me that the mixer was full of limescale and it would be £590 + VAT to replace. Obviously this is a large amount of money and after finding Mike's website I'm a little unsure about his diagnosis. Looking at the common faults of the pulsacoil this doesn't seem to be one of them and he didn't take the mixer off or look inside it but diagnosed it by twisting the mixer cap. He said the immersions were both fine but didn't use a multimeter on them.

I know my question is a bit vague, but if anyone has any advice that they can give then I would be really grateful.

Thanks in advance
Bec

Hi Bec,

I would advise you to call a different engineer, try looking at the engineers page on here for someone local.

Im not sure which Pulsacoil you have but if it is a Brawa mixer valve required they cost little over £100.00 and to fit it would be about £60.00 - £100.00 .

Without carrying out tests though don't go buying a valve which might not be needed!

Hope this helps

Gary

Hello,

I am having a little trouble with my hot water, and have seen that it seems you've had exactly the same problem as me.

I have a Pulsa Coil (again not sure which one), the label on it, just says Pulsa Coil, so I guess it’s just a standard one. Anyway, I'm getting very little hot water from the taps, but I'm quite sure that the water in the tank is plenty hot enough, because when I leave it for a while, and touch the "hot water to taps" pipe that come out of the tank, its blisteringly hot. I've had the mixer changed a couple of times before, I think it worked on some occasions and not on others.

I was interested to find out if your problem was resolved or not, and if so how? Did you need to get a new mixer and if so where from? I don't wanna get fleeced with another expensive plumber bill.

Any help is appreciated.

Regards
John

Hi John,

Dependent on which Pulsacoil you have, It could be either the brawa mixing valve or dhw /phe return sensor that has failed.

If you are ok at DIY they are both a simple fix.

Kind regards

Gary

MK Group Limited

Hi Gary,

Thanks for that. How do I know which Pulsacoil I have. The lable doesn't seem to indicate?

I'm OK at DIY and can use a spanner so am quite confident to do it myself.

I've managed to get a picture on the mixer if that helps? [img][/img]

The cap says oventron on it.

Thanks
again
John

That is a standard mixing valve, sometimes called blending valve. Simply to change and readily available.

Part No is XC007.

Should cost no more than £100.00 and take little over 25mins to fit.

Hi again,

I purchased that part, it arrived today and I've fitted it simply enough. I have hot water back but now the pressure on the hot water is reduced. I think there may be an air bubble in the system, could that effect it? How do I get it out?

Again, any help is appreciated.

Thanks John

Hi John,

Sounds like you have a blocked cold feed. Try draining some water off of the tank and see if the water drains from the F & E tank, let me know your findings.

Kind regards

Gary

Hello.

At the risk of sounding thick, what's the F & E tank? Also I have a tap at the bottom of my water tank do you want me to drain it from their?

That doesn't make a lot sense because the water in the tank never gets used it only heats the pipe inside. There is (I think) a smaller tank directly on top (within the same tank), is this the F & E tank? How do I drain that?

Changing the mixer was easy enough, but that's where my plumbing expertise end I'm afraid.

Can you offer any more help?

Thanks
John

The F & E tank is the small tank on top, drain the larger tank at the bottom and see if the water drains from the smaller tank above.

Kind regards

Gary

MK Group Limited

Hello

Ok I drained some water from th bottom tap. As it started to drain, the water in the top tank started to fill itself up again. The pressure isn't any better. but the water is nice and hot, but just at a slowish trickle.

Any other thoughts?

Again, thank you so much for all your help.

John

When you isolated the water supply for the replacement of the mixer valve where did you isolate it from? was it the mains?

Also have you installed the mixing valve the right way around?

Yes it was at the mains. A tap under the kitchen sink which cuts if all water to the flat.

And yes, it's definitely on the right way round, I'm not as dim as I sound

I would suggest that you drain and remove the F & E tank, and with the drain pipe connected to the tank, connect a cold main pressure feed to the inlet and let the cylinder flush through, It sounds like you have a blocked cold feed.

Kind regards

Gary

MK Group limited