Thermostatic Shower Valve

jc1001

Hello hello. A quick query about thermostatic shower valves for those of you out there with some plumbing know-how. I had a shower installed earlier in the year but since installation have had trouble with the temperature adjustment. It appears the valve would not maintain a constant temp and then an automatic shut-down would kick in when it got too hot resulting in a unexpected cold temp - needless to say this means the shower is practically unusable. Plumber says he tried to adjust the shower but it may need 'specialist' adjustment <like what, em, maybe a plumber?> I got a replacement barrell (thermostatic capsule, not sure what the correct terminology is) from the supplier <very helpful> shires in tallaght and switched it myself but still the same problem. I did notice that the original plumber had broken a plastic collar that went on under the chrome fitting, and the new one that came with the new barrell has limited the temperature range (rotation of the knob) available somewhat, but it is still not ideal. Now to get to the nub of the question - the temperature seems to be increasing when I turn the nob (with the cover off) clockwise, i.e. when, to me, it appears I am closing or tightening the valve, the temperture is increasing. This goes contrary to the indicators (celsius indicators) on the chrome temperature knob also, ie. lowest is 20C and turing it anti-clockwise goes up to 35C and then some more with a safety button press. Could it be possible that the plumber fitted the hot and cold feeds on the wrong sides of the valve? I hope not as will have to crack open a stud wall and some tiles otherwise. Is it possible to adjust these valves to the extent that where it is taking the hot and cold feed from is configurable? Hope this is not too stupid a question - any advice gratefully received.

EireRoadUser

This reply is only an assumption on several things.

If the shower has a pump fitted and the pipes are on the wrong way around on the pump ,this might cause the problem.
On a pump there is a switch for turning on the pump which is on the cold side ,which means the cold always comes on first.
If and it's a big if ,the pipes are mixed at the pump your shower might be getting a hot charge at the start and the temp is kicking in too high.

You shouldn't have to go near your wall ,if it's done right you can trace the pipes back to an access point.

Edit : If your cold pipe is air locked ,this might cause the problem if you have no pump.

Hope above is of some help.

Viking House

I installed a few Thermostatic valves, one of them I put the pipes the wrong way round and only the cold water worked.
Maybe different models work differently but definately there is a correct side for hot and cold.

EireRoadUser

An air locked pipe can have water coming from it ,it can weaken every so often though.

jc1001

Thanks for the responses chaps. I think the pump connection is correct, as it is pumping everything upstairs, and no issues with any other appliances. Defintely the way it is working at the moment is when you turn the heating control down (going by the scale printed on it) the temp is going up, and when you have it at the lowest level the water is at it's hottest - any hotter then you hear a click and the water goes cold - safety shut-off I guess. Will keep you posted on any progress.

jc1001

Further update - I had a look at the piping going into the valve - the t-shaped piece where the hot and cold feeds are attached is clearly labelled red for hot, blue for cold, but the pipes are the wrong way around - staggering. Even an amatuer should not have mucked up this part. To get at the pipes in the enclosure I would have to remove tiles / plasterboard, and the floor is fully tiled too, so I think I'll see if I can access the pipes somewhere along the way where the access is easier, cut them and reverse them with some pluming fitting. Thanks again for the replies.