Ariston
Ariston Thermostat Regulation 999577
Ariston 999577 is a regulation thermostat for Microsystem 21 RFFI and 28 RFFI gas boilers.
At a glance
- Appliance family: Ariston Microsystem 21 RFFI and 28 RFFI
- Also known as 1577714
£39.00
£32.50 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 Ariston 999577 is a thermostat (regulation) for Ariston Microsystem 21 RFFI and 28 RFFI gas boilers. It forms part of the boiler's temperature regulation system, helping the appliance maintain the required operating temperature. This component is listed for the Microsystem RFFI models and serial ranges shown below.
Signs this part needs replacing
- Boiler temperature is difficult to control or runs outside the set range.
- Heating or hot water temperature fluctuates without changes to the controls.
- Boiler cycles on and off more frequently than expected.
- The appliance fails to respond correctly to temperature demand.
- Temperature regulation faults appear during normal operation.
Before you order
- Confirm the appliance model is Ariston Microsystem 21 RFFI or 28 RFFI.
- Check the serial number falls within the relevant range where listed.
- Verify the existing thermostat regulation part number is 999577.
- Check the GC number against the appliance data badge where applicable.
Compliance
| Barcode / EAN | 5411692341985 |
|---|---|
| Alternative numbers | 1577714 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ARISTON ARISTON MICROSYSTEM 21 RFFI - FROM SERIAL No 2320021100001 TO SERIAL No 2320030800001 | — | — | — | |
| ARISTON ARISTON MICROSYSTEM 28 RFFI - FROM SERIAL No 2320021100001 TO SERIAL No 2320030800001 | — | — | — | |
| ARISTON MICROSYSTEM 21 RFFI LPG EDITION 1 (AUG 2000) | 41-116-06 | 41-116-06 | — | — |
| ARISTON MICROSYSTEM 21 RFFI LPG EDITION 2 (JAN 2004) | 41-116-06 | 41-116-06 | — | — |
| ARISTON MICROSYSTEM 21 RFFI LPG EDITION 3 (SEPT 2004) | 41-116-06 | 41-116-06 | — | — |
| ARISTON MICROSYSTEM 21 RFFI NG EDITION 1 (AUG 2000) | 41-116-06 | 41-116-06 | — | — |
| ARISTON MICROSYSTEM 21 RFFI NG EDITION 2 (JAN 2004) | 41-116-06 | 41-116-06 | — | — |
| ARISTON MICROSYSTEM 21 RFFI NG EDITION 3 (SEPT 2004) | 41-116-06 | 41-116-06 | — | — |
| ARISTON MICROSYSTEM 28 RFFI LPG EDITION 1 (AUG 2000) | 41-116-07 | 41-116-07 | — | — |
| ARISTON MICROSYSTEM 28 RFFI LPG EDITION 2 (JAN 2004) | 41-116-07 | 41-116-07 | — | — |
Showing 10 of 14 compatible appliances.
Documents & drawings
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