4
3. Pipe Connections
2. Preparation of installation area
2.1 Positioning the unit
The PAW cylinder should be fitted level on a hard surface with sufficient load strength to take the full weight of the
cylinder (see technical data table page 11). The unit has 3 built-in adjustable feet to allow fine adjustment of the
water heater.
There are no limitations regarding the fitting distance from walls etc., but it is strongly recommended to ensure easy
access to all pipe fittings etc. The Temperature and Pressure relief valve and immersion heater are positioned at
90° apart. The PAW cylinder must be positioned to ensure that the tundish is visible and there is easy access to the
thermostat and to remove the immersion heater if required.
2.2 Protection from frost
If the water heater is in danger of being exposed to frost while not operating under electric power, the unit must
be drained to avoid damage. Make sure the electric power is turned off before draining, otherwise the heating ele
-
ments can be damaged and the warranty is void. Draining instructions, see “Draining ” on page 5.
3.1 Cold water supply
3.1.2
To obtain the best performance from your PAW unvented system it is advisable to feed the unit with an unin
-
terrupted supply.
3.1.3
Before connecting to the multibloc, flush the cold supply pipework of all flux and debris.
3.1.4
Locate the cylinder in a suitable position to facilitate the installation of the cold water supply, discharge fittings
and pipework. Also take into account access to the immersion heater.
3.1.5
Fit the combined male elbow drain cock to cold supply point (12) and make CW pipe in accordance to Gen
-
eral Layout on page 3.
3.1.6
Fit the Multibloc(3) to the CW pipe.
3.1.7
Connect 15mm copper tube from the expansion relief valve (4) and also from the T & P valve (5) and join
together in a Tee as shown on page 3.
3.1.8
Fit the tundish (6) to the bottom connection of this tee.
3.1.9
Connect the cold supply to the multibloc(3).
3.1.10
Fit the expansion vessel to the wall close to the water heater using the enclosed mounting bracket. Connect
the expansion vessel to the multibloc, as shown on page 3.
3.2 Hot water supply
Connect the hot water supply pipe to the outlet (11). Ensure connection is water tight.
3.3 Balanced cold water supply (optional).
If no balanced cold supply is required, tighten the supplied blanking cap. If a balanced mains pressure cold water
supply is required to a shower or bidet (over rim type only, ascending spray type requires type AA,AB or AD air
gap), remove blanking cap and connect to the shower or bidet cold supply on the multibloc valve (3).
(Major shower manufacturers advise fitting a mini expansion vessel in the balanced cold supply pipework to ac
-
commodate thermal expansion and prevent tightening of shower controls) Using the balanced cold connection to
feed bath taps can reduce the flow available to the unvented cylinder.
3.4 Secondary return (optional)
Connect secondary return if required to connection 16 (page 3).
3.5 Discharge pipe
Connect the tundish outlet to the discharge pipe. Install the Tundish in a vertical position within a maximum of
600 mm from the Temperature and Pressure Relief Valve drain connection and away from electrical components.
Ensure the expansion relief pipework discharges through the tundish. Tundish pipework must be 22 mm with a
minimum vertical length of 300 mm below tundish. Maximum permitted length of 22 mm pipework is 9 m. Each
bend or elbow is equivalent to 0.8 m of pipework. All pipework must have continuous fall and discharge in a safe,
visible position. If any doubt, refer to Building Regulation G3.
Discharge pipe must be dedicated to the cylinder and must not be used for any other purpose.
Summary of Contents for PAW-TD20C1E5-UK
Page 16: ......
