15 replacement of parts, 26 hydroblock and bypass tube – Glow-worm Ultracom cx User Manual

Page 62

15 Replacement of Parts

15.26 Hydroblock and Bypass Tube

For access, refer to section 15.1.
IMPORTANT: To replace the bypass tube and seals the LH

and RH hydroblocks will need to be removed. The following

procedure must also be used for the replacement of either the

LH or RH hydroblock.
Refer to section 15.1 and drain the boiler heating circuit and

the boiler domestic water circuit.

Diagram 15.19

13331

Disconnect the CH flow, return and DHW inlet pipes at the

bulkhead connectors, then the retaining clips, remove the

pipes and “o” ring seals.
Remove the low water pressure sensor as described in

section 15.21.
Remove the flow sensor as described in section 15.22.
Remove the 3 way valve as described in section 15.24.
Remove the pump as described in section 15.17.
Remove the plate to plate heat exchanger, refer to section

15.25.
Disconnect the central heating flow at the heat exchanger

connector then remove the retaining clip at the hydroblock.
Disconnect the pipe and “O” ring.
Remove clips from the plastic LH and RH hydroblocks

retaining the DHW, DCW and heating flow pipes, see diagram

15.20.
Remove the CH filter from the heating flow pipe port in the LH

hydroblock. The filter is a push-fit in the hydroblock port.
Grip the LH and RH hydroblocks simultaneously and lift clear

of the spigots on the mounting bracket.
NOTE: Before removing the bypass tube from the

hydroblocks, take note of the tube position and orientation.
Fit the new bypass tube with new ‘O’ ring seals and re-

assemble to hydroblocks.
Before refitting the plate to plate heat exchanger ensure that

the four rubber seals are in place, two in the LH and two in the

RH hydroblock.
Fit new ‘O’ rings to pipes.
Refill system, vent and pressurise the boiler.

13588

PLATE TO PLATE

RUBBER SEAL

(4 OFF)

SPIGOT (4 OFF)

RH HYDROBLOCK

DCW INLET

RETAINING CLIP

LH HYDROBLOCK

DHW OUTLET

RETAINING CLIP

MOUNTING

BRACKET

BYPASS

TUBE

RETAINING

CLIP

CH FLOW

(from heat

exchanger)

FILTER

(in Hydroblock)

CH FLOW

DCW INLET

DHW OUTLET

3 WAY VALVE SEALS

Diagram 15.20