Optional Immersion Heater; How To Drain Hot Water Storage Cylinder - Potterton Powermax HE 85 Litre Installation And Servicing Instructions

- +
H.W. TEMP
SEL
POWER
MAINS ON BURNER LOCK OUT RESET C.H. ADVANCE PROG
N L T T N L F HW HW CH CH
R L 2 2 R R L R L
Valve
Optional
Immersion Heater
Immersion Heater Wiring
Element (connections
under thermostat)
Thermostat
N
Cut-out
Reset Button
Fig. 14
22
Installation
+ SEL
- PROG
RWC
Drain
Double
Check
Valve
Temperature
Adjustment
L
Earth
Post
L N E
Cable
Grip
2.7

Optional Immersion Heater

This heater is rated 3 kW at 240 V only and must be wired to a
totally separate, suitably rated main supply. THERE MUST BE
NO INTERCONNECTION WITH THE WIRING TO THE
BOILER.
Warning: THIS HEATER MUST BE EARTHED.
It should be installed in accordance with the current IEE wiring
regulations and be wired through a double pole isolating switch
or a suitable controller. The heater must be fully immersed and
not switched on dry. Secure cable grip using only screws
provided.
This immersion heater has a special 1 3/4 " BSP thread. It is not
interchangeable with standard immersion heaters. Use only the
'O' ring seal provided. The use of any sealant on the 'O' ring is
not recommended.
The heater must be wired with 85 °C rubber insulated HOFR
sheathed flexible cable 1.5 mm
8. The outer sheathing should be secured using the cable grip
fitted and routed away from the boiler through one of the
bushings provided.
The heater is controlled by the rod type thermostat fitted.
A temperature setting of 65 °C is recommended and is factory
pre-set. This should be reduced to 55 °C (No. 3 on dial) in hard
water areas.
The thermostat incorporates a thermal cutout which cuts the
power to the immersion heater in an overheat situation. Should
this operate it can be manually reset by pressing the red button
to the side of the temperature adjustment dial.
Note: Investigate the cause of the overheating prior to resetting.
Should the immersion heater require replacement, use only the
Powermax spare part P3223/5106143.
2.8

How to Drain Hot Water Storage Cylinder

Isolate mains water supply at stop valve on Inlet Control Group
and close ⁄-turn valve (handle at 90° to valve body) on double
check valve - see Fig. 14.
Fit a hosepipe to the tail of the drain valve (secure with "Jubilee"
clip), and run open end to a low level where water can be safely
drained.
Open nearest tap(s) fully (to allow air to enter cylinder) before
opening the drain valve above hose. Note: The lower the open
end of the hose, the faster will be the draining effect.
When refilling: check that the secondary expansion vessel pre-
charge pressure is between 2.5 to 2.7 bar and allow water to
flow freely before closing tap(s).
2 complying with BS 6141 Table
Publication No. 5106226