General Fitting Information
The Aquatherm range of immersion heaters are direct equivalents to the
immersion heaters fitted to Heatrae Sadia Megaflo cylinders. Please refer to the cylinder manual to identify
the immersion heater by the OEM part number, then to the table to choose the correct Tesla replacement.
To remove the old immersion heater:
1. Disconnect the supply wires from the thermostat.
2. Pull the thermostat away from the immersion heater which will expose the brass housing.
3. Unscrew the brass housing using the special key (Tesla Part no. TIHSIK) and remove the immersion heater.
Note the orientation of the original heater – the replacement should be orientated in the same position.
4. Ensure the rubber seal is also removed.
Re-fitting the Aquatherm replacement.
1. Check the seating face for the immersion heater is clean and free from debris.
2. Ensure the new rubber seal supplied is located properly on the immersion heater flange
3. Carefully feed the immersion heater into the cylinder and orientate it in the same position as the one that
has just been removed.
4. Refit the brass housing ensuring it does not foul on the rubber washer and tighten it using the special key.
5. IMPORTANT NOTE: As the back nut provides the earth contact between the cylinder casing and the heating
element; sealing product MUST NOT be applied to the threads as this will compromise the earth bond.
6. Refit the thermostat, taking care to locate the spade terminals properly in the thermostat
receptacles.
7. Finally connect the supply wires to the thermostat.
8. Test and check for leaks.
Thermostat – IMPORTANT – PLEASE READ
Some early models of the Megaflo cylinder were fitted with a Cotherm type TSE thermostat and used a dif-
ferent design of element to work with this thermostat. The replacement immersion heater is not designed to
work with the TSE thermostat and if this is fitted then the over temperature safety cut-out will not work. If you
require a replacement thermostat these can be purchased through your element supplier.
Later models of the Megaflo cylinder were fitted with a Cotherm type TSR thermostat and this can be used
with the replacement immersion heater.
Tesla UK Ltd, Unit 3b First Avenue, Minworth, Sutton Coldfield, B76 1BA
Tel: +44 (0) 121 686 8711 Technical: +44 (0) 121 686 8733 [email protected] www.teslauk.com
Wiring connection to thermostat
Fitted immersion heater showing back nut
Do not use Cotherm type TSE thermostat
with the replacement element
Do not use PTFE tape or sealing paste
on back nut threads
Neutral
Live
Earth wire to
terminal block
on earth stud
Specialist Immersion Heaters by Tesla UK
Tesla Code OEM Code
TIH101K 95606961
TIH103K 95606962
TIH105 95606989
TIH106 95606988
TIH107 95606986
TIH108 95606984
