Navien
Navien Printed Circuit Board 30021891A
Printed circuit board for Navien LCB 700 Combi boilers, controlling ignition, modulation and safety functions.
At a glance
- Part type: printed circuit board
- Appliance family: LCB 700 Combi
£177.91
£148.26 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The printed circuit board is the main control board for Navien LCB 700 Combi boilers. It manages ignition sequencing, burner modulation, pump and fan control, and the boiler's safety interlocks. This board is listed for the LCB 700 Combi range in both internal and external variants.
Signs this part needs replacing
- Boiler has no power or display, with the board showing no response when the supply is confirmed live
- Repeated lockouts or fault codes that clear only briefly after a reset
- Burner fails to fire despite a call for heat and confirmed gas supply
- Fan, pump or diverter no longer respond to demand
- Intermittent operation or erratic behaviour from the controls and sensors
Before you order
- Confirm the boiler is an LCB 700 Combi and note whether it is the internal or external variant
- Check the output rating of the appliance against the fitment list
- Read the part number from the existing board and match it to 30021891A
- Confirm the fault is traced to the board before ordering, as several symptoms share causes with sensors and wiring
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| NAVIEN LCB 700 COMBI EXTERNAL 21KW (Serial Number 1705) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 21KW (Serial Number 1705) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 28KW (Serial Number 1710) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 28KW (Serial Number 1710) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 36KW (Serial Number 1709) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 36KW (Serial Number 1709) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 21KW (Serial Number 1704) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 21KW (Serial Number 1704) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 28KW (Serial Number 1706) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 28KW (Serial Number 1706) | — | — | — |
Showing 10 of 12 compatible appliances.
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
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