Navien
Navien High Limit Stat 30002557A
High limit stat for Navien LCB 700 combi, regular and system boilers, part number 30002557A.
At a glance
- Part type: high limit stat
- Appliance family: LCB 700
£4.64
£3.87 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 high limit stat is a safety thermostat used on Navien LCB 700 series boilers. It monitors boiler temperature and interrupts the burner circuit if the appliance overheats, preventing damage to the heat exchanger and other components. This part is supplied under Navien part number 30002557A.
Signs this part needs replacing
- The boiler locks out or shuts down once it reaches operating temperature
- Overheat or high limit fault codes appear on the boiler display
- The appliance runs briefly then cuts out, repeating on each demand
- Heating and hot water stop until the boiler is reset
- The stat fails to interrupt the burner circuit when the boiler overheats
Before you order
- Confirm your appliance is a Navien LCB 700 and match the model variant, output and internal or external format against the fit list
- Check the part number on the existing component against 30002557A
- Verify the serial number of your appliance where the model listing specifies one
- Confirm whether the fault lies with the high limit stat rather than the thermistor or control board before ordering
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 36 compatible appliances.
Documents & drawings
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