Ideal
Ideal Expansion Vessel 25 Litre Solar 174859
Ideal 174859 solar expansion vessel, 25 litre, for Ideal Solar Pack and Thermostore solar thermal systems.
At a glance
- Part type: Expansion vessel
- Also known as 1780540
£158.47
£132.06 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 Ideal 174859 is a 25 litre expansion vessel for Ideal solar thermal systems. It absorbs the change in volume of the heat transfer fluid as the collector circuit heats and cools, holding system pressure steady inside the sealed solar loop. It sits within the Ideal solar range, which covers the Solar Pack collector sets and the Solar Thermostore cylinder.
Signs this part needs replacing
- System pressure drops repeatedly and the loop needs regular topping up
- Fluid discharges from the solar circuit pressure relief valve as the system heats
- Fluid or water weeping from the air valve on the vessel
- Corrosion, blistering paint or fluid staining on the vessel shell
- Pressure gauge swings widely between cold and hot conditions
Before you order
- Check the appliance model against the compatibility list below before ordering
- Confirm the part number on the existing vessel; 1780540 is also listed against this item
- Have the model and serial details of the solar unit to hand when checking
Mechanical
| Part type | Expansion vessel |
|---|
Compliance
| Manufacturer part number (MPN) | 174859 |
|---|---|
| Barcode / EAN | 5022141748592 |
| GPC classification | Central Heating Replacement Parts/Accessories |
| Alternative numbers | 1780540 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| IDEAL SOLAR PACK 1 (1 COLLECTOR) | — | — | — | |
| IDEAL SOLAR PACK 2 (2 COLLECTORS) | — | — | — | |
| IDEAL SOLAR PACK 3 (3 COLLECTORS) | — | — | — | |
| IDEAL SOLAR THERMSTORE 180 | — | — | — | |
| IDEAL SOLAR THERMSTORE 210 | — | — | — | |
| IDEAL SOLAR THERMSTORE 250 | — | — | — | |
| IDEAL SOLAR THERMSTORE 300 | — | — | — | |
| IDEAL SOLAR THERMSTORE 400 | — | — | — | |
| IDEAL COMMERCIAL IDEAL COMMERCIAL PARTS | — | — | — |
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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