No hot water in shower

Thoie

Just wondering if anyone has any theories.

I have an air to water heating system that seems to be working fine. Since Friday, the shower in the ensuite has been barely lukewarm, but there's plenty of hot water going to every other tap (including to the sink in the same bathroom). There's obviously some hot water getting there, as it's not freezing, but it's not as hot as usual, not as hot as the water from the sink tap, and not hot enough to rinse conditioner from my hair. I took the "handle" that controls the water temperature off, and there's nothing obvious wrong there. It was a little stiff, so I sprayed some WD40 on it. It's now less stiff, but the water temperature isn't increasing.

Sleeper12

Possibly a blocked filter or faulty thermostatic cartridge

Thoie

Sleeper12 wrote: »

Possibly a blocked filter or faulty thermostatic cartridge

Thank you. I was thinking a thermostat, and expected to see one when I took the "cover" off, but it looked quite mechanical.

The overall shower is shown in picture marked "shower". The "water on off" shows what the controls look like from the side (it was easier to get that angle for the on/off than for the temperature. The "inside hot cold" picture shows what was underneath the cover for the temperature. That was a little stiff, so I sprayed it with some WD40 and wiggled it.

Would there be a thermostatic cartridge further behind that again? Maybe in the main "bar"? I couldn't see how to remove the "temperature" end any further - next step would be to remove the whole shower fitting from the wall.

Sleeper12

The thermostatic cartridge is going to be on the tempeture dial. There isn't much point removing it until you are certain you can source a replacement cartridge though. Depending on the make, model & age you might have to replace the whole shower

Thoie

Sleeper12 wrote: »

The thermostatic cartridge is going to be on the tempeture dial. There isn't much point removing it until you are certain you can source a replacement cartridge though. Depending on the make, model & age you might have to replace the whole shower

It was installed as part of a new build 2 years ago, and can't see a make/model, so may just have to replace the whole thing. Short term I've seen some videos about descaling, so depending on how enthusiastic I feel later I might give that a go, though I doubt it will help, as it's not a hard water area. It will be a few days before I can get somewhere for a replacement unit. Thanks for the guidance though.

Sleeper12

The shower itself could have a two to 12 years warranty, depending on the make. Have you tried contacting the builder?

Thoie

Sleeper12 wrote: »

The shower itself could have a two to 12 years warranty, depending on the make. Have you tried contacting the builder?

Therein lies a tale...

I'll give it another try, but there's a litany of plumbing issues, and the builder is refusing to engage. My solicitor is on the case, but there's a balance between the cost of legal action vs the cost of just fixing things, and putting up with inconvenience in the interim. I also need to find a plumber who would be willing to write a report (that I'd pay for) outlining all the flaws, for use in a court case, and haven't found one so far who's willing to do so.

I've been advised that "hanging, drawing and quartering" is no longer one of the penalties for shoddy workmanship, and to be honest that would be my preferred option right now.

whizbang

You should be easily able to unscrew the cartridge, Its temperature control end. There is a large mesh filter around the outside of mine, easily blocked.
Put a bucket under the cartridge end when you are taking it out, in case anything falls out, and you will get to see if there is any debris in there. Flush out by turning water on without the cartridge, and check again for debris, And hot water!

youtheman

1. did you unscrew the hose and see if there was hot water coming out?. Possible that the shower head is partially blocked which will cause problems with flow and pressure and this might influence the way the hot/cold water is mixed.
2. did you check the temperature on the two feed pipes coming out of the wall (into the mixer unit). If one pipe is hot and you can't get hot water out of the shower head then this might imply that the mixing cartridge is faulty.

Thoie

youtheman wrote: »

1. did you unscrew the hose and see if there was hot water coming out?. Possible that the shower head is partially blocked which will cause problems with flow and pressure and this might influence the way the hot/cold water is mixed.
2. did you check the temperature on the two feed pipes coming out of the wall (into the mixer unit). If one pipe is hot and you can't get hot water out of the shower head then this might imply that the mixing cartridge is faulty.

Will do both of those too, thanks. The hot feed pipe coming from the wall feels hot on the outside, but haven't unscrewed it all and checked actual temperature. The shower head doesn't appear blocked, but as that's the easiest, I'll take it off and rinse it through first.

Thoie

Thanks all for the help. Couldn't get the thermostatic cartridge out for love nor money, and couldn't find a brand anywhere on it to buy a replacement anyway. Even with the whole thing off the wall I can't get the cartridge out.

Bought a new shower, fitted it this afternoon in 10 minutes, all good now. I'll calibrate the temperature over the weekend, but it's not far off "right" anyway.

The "default" marking on the shower is 38 - other than confusing/scalding other people, is there any mechanical reason I shouldn't calibrate that position to 40? I like hotter showers.

whizbang

No issue with the 38..

Well done on that 10mins job.

Thoie

whizbang wrote: »

No issue with the 38..

Well done on that 10mins job.

Thanks, didn't have time to do the calibration yet (I could have made the time, but chose to spend it doing other things!). I read the manual (after fitting, of course), and there's some mention that the max operating temperature of the cartridge should be x degrees (possibly 46). I'm not around for a few weeks, but will play with the calibration when I get back.


Just thinking out loud here:
The recommendation is to put the temp to the 38 marking and calibrate to that. I might take the opposite tack, and put the temp to max, and calibrate the max to 46 (or whatever was recommended). My only concern with doing that is could/would the incoming water temperatures fluctuate during the year? In theory my water heater is thermostatically controlled as well, but in cooler weather I often feel that I need to turn up the temperature a bit. This is probably due to the cold intake being cooler in winter?

We're probably at close to the warmest time of the year at the moment, so maybe if I calibrate the max temperature to x-1 (45), that would allow for seasonal variations.

If anyone sees any flaws with my musings, I'd appreciate feedback. As you'll have gathered, I'm not a professional plumber.

Sleeper12

The cartridge is usually factory set at a good tempeture for showering. Maybe 1 in every 1000 / 500 clients ask me to set it higher. I'd suggest trying it out before you adjust it. What you need to worry about is the tempeture of the water in your hot water cylinder. If this is too hot it will damage the new cartridge & void any warranty