SO I plodded around on t'internet and discovered that the thermostatic valve inside the shower may be clogged up with limescale. Who knew there was something INSIDE the shower that needed maintenance?? not me.
A thermostatic valve mixes hot and cold water to a safe and stable temperature to avoid scalds, especially with children. A thermostatic valve can be in a tap, a shower or at the outlet of a hot-water tank (or theoretically anywhere on a hot-water pipe)
We had 2 options - replace the shower - try to clean the thermostatic valve. Being a Make Do and Mend kind of gal, I found a youtube video, rolled up my sleeves, and got stuck right in.
Should you be inspired to fix your own shower - remember to read our disclaimer first.
We installed the shower ourselves 4 years ago. I should say we bought the shower straight from the manufacturers - Bristan, and I contacted their customer service line and technical support team first, they were no help, didn't carry spare parts for this model, but also wouldn't give me any technical advice on how to service the shower. This really annoyed me, how hard can it be to give some technical support on something you run a technical support line for?
Anywhoos, it is a fairly standard bar shower and it was worth attempting to fix it before replacing it.
Here's the brilliant video that showed me how (thanks for nothing Bristan):
At the 'temperature' end there is a little cap that can be prized off with a flat- head screwdriver, once that is off you can undo the grub screw taking the end off and exposing the internal gubbins.
Frustratingly we had a plumber put in the pipework for our shower during the building of the extension - he didn't leave space for an isolator valve - so the water had to be off at the mains throughout - THIS is why we do everything ourselves.
Now in theory I should have removed the thermostatic cartridge then - but as I pulled I was concerned that the tiles would break. I decided I couldn't manage this in situ and so I unscrewed the shower from the wall at this point. On our shower we can just unscrew the pipe fittings at the back so that is simple enough (and I probably should have done it at the start)
Anyway, it was a bit of a struggle but once I removed the thermostatic cartridge and checked, it didn't seem to be clogged up. I put it in some very hot water with a good splash of vinegar to get rid of any limescale.
While I had the shower off of the wall I realised how filthy it was so sat with a cup of tea and took the whole thing apart and gave it a thorough clean inside and out.
After I had left the valve soaking for around 30 mins I put the nice clean shower back together and back on the wall.
Showers were no longer ice cold but the water was still not coming through hot... our next idea was to climb up to the loft and adjust the thermostatic valve coming out of our hot water tank. This was a little trickier at first and really deserves its own post but, it was dark and we couldn't take photos.
Basically John removed a safety cover from the thermostatic valve and slowly adjusted the tap underneath - All the while, I was on the phone to him with a thermometer under the bathroom tap reading back the temperature to him. When we started the maximum temperature was only 34°C (a warm shower should be calibrated to 38°C) we increased the hot water temperature to 44°C so now when it is mixed through the immaculatly clean, good as new, shower - it comes out lovely and warm.
We think the problem came from the cold weather dropping the cold water temp down to 3°C which, when mixed with our hot water just made it too darned cold. It had always been wrong, we had just never noticed before.
Now the problem is all sorted. Nice warm showers for one and all.
If you have read this and are inspired to fix stuff in your own house read this first - Thankyou x