Deva SP037 Thermostatic Cartridge for Regent, Expression and Vista Shower Valves (SP037/REGENT) - Compatible SpareThis cartridge is used in the following models of Deva (and Sag) shower mixers: - Deva Expression Exposed Thermostatic Shower Mixer Valve - Deva Expression Recessed Thermostatic Shower Mixer Valve - Deva Vista Thermostatic Bar Thermostatic Shower Mixer ValveDeva SP037 Technical Information - Total Length: 110mm - Width at Widest Point: 41mm - Number of teeth on spline: 20 - Width of top spline: 7.8mm - Number of Filters: 2 (however there is no gauze on this cartridge) - Material: Brass - Colour: Gold / Brass - Colour: TMV2 Approved Shower Spares Overview: Deva SP037 Thermostatic Cartridge Is your shower valve a Deva Regent, Expression or Vista? Then, you can be sure that the Deva SP037 is the thermostatic cartridge you need to complete a successful shower repair. What if you’re not very sure of the make and model of your shower valve? How will you know if the SP037 is the replacement spare cartridge for your shower? Read below for information about thermostatic cartridges, how it becomes faulty, and how to determine the right cartridge for your shower. Having a fully functional Deva SP037 thermostatic cartridge is essential for a good showering experience. Water goes in the two filters (one for hot and the other cold) where a wax thermostat capsule mixes it together to attain the temperature set at the handle. (The bottom of the tiny wax thermostat can be seen in the second photo in the gallery above.) A mix of hot and cold water by 50/50 results in lukewarm shower temperature. The wax capsule inside the Deva SP037 will adjust the hot and cold mix to produce the preferred temperature. Water is then released from the shower head. The Deva SP037 thermostatic cartridge has four O-rings. The O-ring, also called a toric joint, is usually made of rubber. This is the cartridge’s means of sealing water within its barrel preventing it from spilling out. D-SLIDEVALVE is the slide valve for this Deva shower thermostatic cartridge. What Damages the Deva SP037 Thermostatic Cartridge The main drivers of a Deva SP037 thermostatic cartridge break down include abrasion and accumulation of hard water minerals.Some of the minerals carried by hard water are dissolved chalk, lime and magnesium sulphates. These minerals can calcify in and around the thermostatic cartridge. The abrasive nature of the hardened minerals can scrape against the moving piston of the Deva SP037 damaging it. This can be why the shower water temperature can be difficult or fail to adjust. The scale can also block the filters of the Deva SP037 thermostatic cartridge inhibiting water from entering. This can cause poor water flow rate. For more information about hard water, please read our Ultimate Guide to Water Hardness. O-rings tend to fail after years of use. It can dry up and develop cracks which can cause water to leak. Is the Deva SP037 the Thermostatic Cartridge for Your Shower Valve? So, you have no idea about the make and model of the shower valve you have to fix. The first element in manually determining if the SP037 Deva cartridge is the correct part is the measurements. Hence, it is important to open the shower valve and remove the thermostatic cartridge. To open the Deva Regent, Expression or Vista shower valve: – Remove the indice from the temperature handle and unscrew the retaining screw. – Remove the handle and the flow control handle (for the Deva Regent and Expression). – Remove the temperature stop ring. (Remember the position of the stop ring because it has to be returned to its original position upon reassembly.) – Unscrew the faulty Deva SP037 thermostatic cartridge to remove it from the valve. If you have a different shower valve, the general rule in disassembling the valve would be to look for the handle retaining screw. It can be located under the handle or hidden under an indice. Remove the screw, the handle and its subsequent parts to access the thermostatic cartridge. Once you have the Deva SP037 thermostatic cartridge, take its measurements using a ruler or tape measure and compare it with the measurements stated above. The number of spline notches has to be taken into account. The number of teeth on spline (20) from the Deva SP037 thermo