cold shower from pulsacoil a class

[Dave99199]

Hi,

We have a pulsacoil a class thermal store supplying hot water to a shower with a T bar mixer.
The shower is no longer providing hot water from the shower.
The pipe feeding the mixer is hot
the T bar has been replaced
It stayed hot for a couple of days and then slowly the temperature dropped
The T bar was adjusted and again after a day it was cold
Maybe we're unlucky in that the new T bar is faulty but weird to have old and new with the same issue.
Does anyone know what could be going on?

Best regards,
Dave

 

[polesapart]

Check your shower inlet filters.

Give your shower pipework a quick blast of water through with mixer removed.

Check for reversed H&C.

 

[Dave99199]

sorry for the late reply. no joy with those suggestions unfortunately.

Now wondering if the water is too hot causing an issue with the T bar thermostat as the water in the taps is very hot.
The local water pressure also seems to increased recently as there are a lot of toilets in the block with water hammer. whilst that's now fixed with a replacement filler I'm wondering if the pressure could also be too high for the T bar?

It now looks like the Pulsacoil A-class appears to be boosting itself when the hot water is used. I thought that it only worked when the boost button was pressed and then switched itself off after a period of time. Could that be a fault?

Also one of the spurs has over heated burning the faceplate. This makes me think an element is running for a long period. I've seen them burn before as they are only rated at 13A and the elements are 3KW.

The plan at present it to fit a pressure regulator on the incoming mains and check / replace the temp sensors so the water is not so hot.
The self boosting is confusing me as to whether it's a feature I can't documented or a fault.

Does anyone know what might be going on?

 

[oldbutnotdead]

Sounds like a list of bad things. First one, are the thermostats set at the correct figure (75 deg c for them) and are they working.

Second, the Boost function - sounds as if the relay or whatever is activated by that button has failed closed (so as soon as you use any hot water that heater chimes in again). You'll be able to see that on your normal electric meter (it'll be flashing about once a second when that heater is active).