Shower keeps coming on cold

[Rocky7]

I recently replaced the thermo cartridge in a Bristan Trinity shower. It was actually the second time I did it as the first replacement proved to be faulty. So I'm assuming the odds are against this one being too.

After a week or so of trouble free showering, I turned it on one morning and the pressure coming out of the shower was much higher than usual and it would only run cold. Adjusting the temperature control made no difference. I took the cartridge out to have a look, replaced it again and the shower was fine. For about two days when the same thing happened again. If I take the cartridge out and re-set it back in it always works OK for a couple of days or so. But eventually it will always trip back to running cold again. I tried Bristan but they just offered to send out an engineer who I would have to pay for. I don't want to go down that route yet. What part of the action of taking the cartridge out and fitting it back in is causing the shower to work OK? So then maybe I can figure out what's causing it.

 

[Riley]

It does sound like a faulty cartridge so I cant understand why Bristan are reluctant to take a look at it without charging. Is it an official cartridge ?

 

[JCplumb]

AFAIK Bristan will come out and if they find a fault with one of their parts they will sort it for free, if it turns out to be a blocked filter or other non-Bristan issue then they charge.
For the price of those cartridges though, and if it's been fitted exposed - I'd have whipped it out and stuck a bar mixer in there, my local indie does a very reliable bar mixer for less than one of those Bristan cartridges.

 

[Rocky7]

For the record, I contacted Bristan again and this time got a totally different response. The guy on the phone said all I needed to do was provide proof of purchase and they would replace it under warranty. I did that by return and two days later a brand new cartridge arrived in the post. I have subsequently fitted it and, four days in, all is well. What that does mean is that two replacement cartridges were faulty before I got to where I am now which is not good but Bristan's response in the end was excellent.