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HXI Engineer Support

Welcome to the Engineer Technical Support section. Please use the different sections below to find answers to your technical questions. You can also find a range of useful contact numbers, including Technical support, here.  

 

Symsi PCB Fault Finding

 

IRIS PCB Fault Finding

Fault Finding Information

 

 

Wiring Diagram

Boiler Clearances

Fault Codes

Click here to access the Fault Codes for this appliance.

Roomstat Wiring

        

How do I setup a replacement Display interface PCB?

Click here to access the replacement Interface PCB instructions.

I have a pulsing / Revving Fan and a Blank or flickering display?

CXI / SXI / HXI / BG330: Revving Fan / Pulsing Fan & Blank Display

The Revving fan can occur on this particular boiler for the following reasons. This is not an exhaustive list. For further guidance check the Installation Manual or contact Glow-worm Technical:

  • A Blank display can be caused by a lack of power to the boiler, a lack of power from the main PC to the Display PCB, J13 Harness, or faulty low voltage component. The following electrical checks can be completed in order to diagnose this issue.
  • 240vac between Red and White on H8 for incoming power from the reset switch. Otherwise this can point to an issue with the reset switch or Fused spur.
  • Internal Fuse continuity. 
  • Continuity testing of the User interface J13 harness from main PCB to display PCB. Voltage testing on the J13 connection from right to left. If these voltages are not correct, this could indicate Component failure. 

 1st track ( red ) = 15 >16vdc from PCB ranging

2nd track ( red ) = 5vdc

3rd track ( red )* =1.7vdc approx

4th track ( red ) = 5vdc approx from interface

5th track 0

NB : 3rd track is the  fault wire. If fault condition. (F code ) this  will show  a fast ranging voltage between 3 > 6vdc.

  • Ease back and reseat the J1, J4 and J2 (cxi only) on the left side of the PCB. A bad contact caused by debris, or a damaged plug can cause a blank display.

A Faulty component on the J1, J2 and J4 harness can cause a blank display. A Fault can include simply unplugging the components individually to see if the display then returns. Otherwise continuity of the harness and electrical testing of the components can be carried out as per table below:

 

 

The 230 volt controls board

With no call for heating and no external clock or link fitted in the low voltage connection block (CXi ) only.

Testing on the PCB connection J15 from left to right, pull edge connection partly  off the PCB just enough to expose enough track to allow access with the multimeter probe, and testing between track and earth.

  • 1st  track ( white ) = 0
  • 2nd track ( red )    = 39vdc approx ( from PCB)
  • 3rd track ( green ) =35vdc from 230 volt interface

Calling for heat. J15 from left to right

  • 1st track ( white ) = 0
  • 2nd track ( red )     = 38vdc approx  from PCB 
  • 3rd track ( white ) = 1.06vdc

 

NB:- Colours changed after august 04 to the following

 

1st wire =black 2nd wire red 3rd wire brown

The hall effect sensor Tap Off (flow switch) not applicable on Hxi or Sxi.

 

With no hot tap on. J2 connection from the bottom connection up.

  • 1st track ( grey ) = 0
  • 2ndtrack ( white ) = 18.22vdc ( from PCB ) approx.
  • 3rd track ( pink ) = 12vdc ( or 0vdc ) from flow switch.

GALAN FLOW SWITCH WHICH IS THE LATEST FLOW SWITCH AND THE VOLTAGE IS SLIGHTLY DIFFERENT

 

The hall effect sensor Tap On

J2 connection again reading   from bottom up.

  • 1st track ( grey ) = 0
  • 2nd track ( white ) = 18.22vdc ( from PCB ) approx
  • 3rd track ( pink ) = 5 > 6vdc ranging. ( from flow switch ).
 

Loss of water pressure sensor

Sensor J1 connection from top down ie first wire. 

  • 1st  track ( orange ) = 5vdc approx from PCB
  • 2nd track ( grey ) = 0
  • 3rd track ( white ) = 1.6vdc approx from sensor
  • if white = 1vdc approx = 0 bar
  • if white = 3vdc approx = 3 bar
 

Display PCB: User interface J13 connection from right to left.

  • 1st track ( red ) = 15 >16vdc from PCB ranging
  • 2nd track ( red ) = 5vdc
  • 3rd track ( red )* =1.7vdc approx
  • 4th track ( red ) = 5vdc approx from interface
  • 5th track 0

NB : 3rd track is the  fault wire. If fault condition

 ( F code ) this  will show  a fast ranging voltage between 3 > 6vdc.

 

Make sure when changing the user board that the wiring harness is fitted the correct way round, see wiring diagram attached.

If it is fitted the wrong way round you will lose the display.

 

Gas Valve

24vdc to lift 12vdc to maintain on rectification

55 ohms across outside pins on the gas valve.

 

 

Ignition Module

59vdc across brown and blue on H2

 

FAN J4 connection

  • Red @ j4 connection 37vdc stationary, 30vdc running
  • Yellow @ J4 connection 1vdc stationary 
  • 2.5vdc to 10.5 vdc running variation due to fan  speed.
 

 

 

Available Literature

 

Installation ManualHorizontal Flue GuideVertical Flue GuidePlume Management Kit

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