Showers need to be calibrated on site whilst they are being installed, this is because they can work differently at different water pressures, Calibration is simply a process of aligning the thermostat, safety device and handle all to 38 Degrees, this in turn allows for the temperature to be increased or decreased by roughly half a turn of the handle the parts can be seen below
When all pieces are correctly installed the thermostat is limited to 1 rotation, as the cartridge is capable of just under two turns it means you can limit how high the temperature can go this not scalding anyone with water that is to hot.
From the factory these thermostats are pre set to a midway point assuming 50 degrees in coming hot and a balanced pressure of 1.5 bar, if your pressure is different or your incoming temperature is different this can affect the calibration meaning you may get to hotter water or to cold.
How to calibrate.
To calibrate you will need a small flat head screwdriver a Phillips screwdriver and something to measure the temperature.
Start by removing the temperature handle this usually involves prising off the Center cap and removing the Center screw., then pulling off the handle. Beneath the handle will usually be a safety ring similar to pictures above this needs to be removed for the moment, then you can refit the handle loosely.
The next step is to turn the shower on and let the temperature stabilise, then adjust until your temperature is reading 38 Degrees allow the water to run for a few mins to ensure its correct, if you can’t get 38 Degrees see fault finding below, once your happy with the temperature turn off the shower and remove the temperature handle.
The final stage is to realign the safety stop with the handle. Inside the handle there’s a pin connected to the safety button, this aligns with change in size of the safety ring see pics below. These then get put back on the valve with the 38 Degree marking aligning with the mark in the valve both are usually on the top of shower so easily visible Although not all valves have markings if not allign the button upright as below.
Then you can screw the handle back on and refit the screw cover.
If your shower isn’t functioning as it should please see below.
1- Shower dripping from head or heads, This is normal after turning off your shower as capilary action can draian the residual water the head and pipes, this should stop after a few minutes, if it doesnt stop the your on/off or divertor (Depending on type of shower) may be faulty or clogged with debris, new parts will probably be needed.
2- Shower temperature incorrect, having checked you have hot water elsewhere (Kitchen sink, Bathroom taps Etc) turn the temperature control as hot as it will go and let it run for a minute or two. do you have A- Only cold water, B- Luke warm water, C- No water, D- Warm / Hot water. A&B both indicate that your thermostat may be seized (This is common in hard water areas) the thermostat needs removing and sevicing. C indicates that your hot water non return valve or filter is clogged / jammed shut this is common if the pipework wasnt flushed when the valve was installed, or you have a combi and its a very short run on the hot side, To remedy, turn off the water and remove the valve or inlets to check filters are clean and non returns are operational see pics below
3- Shower temperature incorrect. having checked all above turn the temperature control to its coldest position and let it run for a few minutes, do you have A- Only hot water, B- Luke warm water, C- No water, D- Cold water. both indicate that your thermostat may be seized (This is common in hard water areas) the thermostat needs removing and sevicing C Inicates that your cold water non return valve or filter is clogged / jammed shut this is common if the pipework wasnt flushed when the valve was installed, To remedy, turn off the water and remove the valve or inlets to check filters are clean and non returns are operational. In both cases above D indicates the shower is working correctly on that side.
4- Temperature control handle doesnt move, this indicates that your thermostat is seized and needs removing to be serviced.
5- Temperature handle appeares to rotate freely or beyond one turn, This indicates your thermostat has failed, most showers are designed with a plastic part (Usually splines) as a weak point so if your thermostat becomes stuck the handle will fail before the thermostat (As the handle is the cheapest part to replace), Remedy- the thermostat needs removing and servicing and possibly a new handle.
In most of the situations above we tend to find that the issue is limescale or debris in the pipes, neither are covered by any manafactures warranty, We offer an in house service, if you bring in your valve or thermostat we can strip clean, check and rebuild / replace as needed, prices vary depending what is required a strip clean and rebuild without parts starts at £15+vat and we will confirm and / or show you what the issue is. this can be done from 9am to 4pm mon-fri only and usually takes about 1/2 hour. if you are having a plumber wait to refit call first on 01603 722339 to confirm we can look at it while you wait.