Sime
Sime Air Pressure Switch 605.99748
Air pressure switch for Sime gas boilers, used to prove fan and flue airflow before ignition.
At a glance
- Also known as AIR-PRESSURE-SWITCH-52-62-PA
£28.78
£23.98 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 air pressure switch 605.99748 is a Sime boiler component that monitors the pressure created by the combustion fan and confirms airflow through the flue before the boiler is allowed to fire. It forms part of the appliance's safety interlock chain, preventing ignition when the fan or flue path is not proving correctly. It is used across a number of Sime gas boiler ranges.
Signs this part needs replacing
- Boiler repeatedly locks out during or shortly after a heat demand
- Fan runs but the boiler does not proceed to ignition
- Fault code or lockout on start-up that clears only after a reset
- Intermittent operation that worsens in windy conditions or with a restricted flue
- Boiler shuts down mid-cycle without a demand-related cause
Before you order
- Confirm the appliance model matches one of the listed fits
- Check the existing switch part number against 605.99748
- Inspect the sensing tubes and fan for blockage or damage before assuming the switch has failed
Compliance
| Alternative numbers | AIR-PRESSURE-SWITCH-52-62-PA |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| SIME CLIMIT GG M 23 BF MET - 8105460 | — | — | — | |
| SIME ECOMFORT 25HE | 47-283-06 | 47-283-06 | — | — |
| SIME ECOMFORT 35HE | 47-283-09 | 47-283-09 | — | — |
| SIME ECOMFORT PLUS 25HE - 8104012 | 47-283-13 | 47-283-13 | — | — |
| SIME ECOMFORT PLUS 25HE SYSTEM - 8104013 | 41-283-10 | 41-283-10 | — | — |
| SIME ECOMFORT SYSTEM 25HE | 41-283-04 | 41-283-04 | — | — |
| SIME FORMAT 30BF TS GPL - 8092983 | — | — | — | |
| SIME FORMAT 80B LPG - 8105401 | 47-283-07 | 47-283-07 | — | — |
| SIME FORMAT 80B NATURAL GAS - 8105400 | 47-283-07 | 47-283-07 | — | — |
| SIME METROPOLIS 25 BF GPL - 8105411 | — | — | — |
Showing 10 of 26 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.
SIME appliance manual — ECOMFORT 25HE (GC 47-283-06), ECOMFORT 35HE (GC 47-283-09), ECOMFORT SYSTEM 25HE (GC 41-283-04)
manualmanualSIME appliance manual — ECOMFORT PLUS 25HE - 8104012 (GC 47-283-13), ECOMFORT PLUS 25HE SYSTEM - 8104013 (GC 41-283-10)
manualmanualSIME appliance manual — FORMAT 80B LPG - 8105401 (GC 47-283-07), FORMAT 80B NATURAL GAS - 8105400 (GC 47-283-07)
manualmanualSIME appliance manual — SUPERIOR 40 MKII - 8098100 (GC 41-719-10)
manualmanualSIME appliance manual — SUPERIOR 40CI - 8098110 (GC 41-719-10), SUPERIOR 50CI - 8098111 (GC 47-719-11)
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