Ariston
Ariston Thermostat 999539
Ariston 999539 thermostat rated 75–65°C for use in listed AS and EGIS gas boiler models.
At a glance
- Also known as 1577688
£19.81
£16.51 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
This is an Ariston thermostat, part number 999539, rated between 75°C and 65°C. It is a control component used in Ariston gas boiler appliances, where it monitors and switches on temperature to regulate boiler operation. It is listed under thermostats within gas boiler spares.
Signs this part needs replacing
- Boiler water temperature drifting above or below the set point
- Boiler cycling on and off more frequently than normal
- Overheating or repeated high-limit lockouts
- Domestic hot water or heating running consistently too hot or too cool
- Erratic temperature readings that do not match the boiler setting
Before you order
- Confirm your appliance model against the fit list above
- Check the part number marked on the existing thermostat matches 999539
- Verify whether your boiler is the CF variant before ordering
- Check the temperature rating on the existing component matches 75–65°C
Compliance
| Barcode / EAN | 5411692339999 |
|---|---|
| Alternative numbers | 1577688 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ARISTON AS 24 CF LPG | — | — | — | |
| ARISTON AS 24 CF NG | — | — | — | |
| ARISTON EGIS 24 CF B | — | — | — | |
| ARISTON EGIS 24 CF LPG | — | — | — | |
| ARISTON EGIS 24 CF N | — | — | — | |
| ARISTON EGIS 24 CF NG | — | — | — | |
| ARISTON EGIS 24 CF NG (EAA1) | — | — | — | |
| ARISTON EGIS 24 CF NG (EAA2) | — | — | — |
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.
No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
No technical questions yet for this part.
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