# Expansion/Diaphragm Vessel CIMM ACS 18 L for Domestic Hot Water, Pressure 2.5/8 bar, Temp -10 to 100 °C

**URL:** https://aio.lv/en/product--cimm-511842--12064609
**Data updated:** 2026-03-12 21:43 (EET)
**Category:** Home Appliance Accessories
**Manufacturer:** CIMM
**Manufacturer code:** 511842
**EAN:** 8033003521700
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 43.99 €
**Prices and availability valid until:** 2026-07-14 23:59
**Price without VAT (21%):** 36.36 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--cimm-511842--12064609

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 07.07.2026 | free |
| Pickup points | 10.07.2026 | 1.99 EUR |
| Courier delivery to door | 10.07.2026 | 4.99 EUR |

## Summary description

CIMM diaphragm/expansion vessel ACS with 18 L nominal volume designed for domestic hot water (c.w.u.). Rated for operating pressures 2.5/8 bar and a temperature range from -10 to 100 °C. Suitable for pressure stabilization and thermal expansion compensation in potable hot water systems, boilers and water heaters. Provides corrosion-resistant separation of fluid and gas via internal diaphragm.

## Long description

CIMM ACS 18 L expansion/diaphragm vessel is designed for domestic hot water systems to manage pressure variations and thermal expansion. The vessel has an 18-litre nominal volume and an internal diaphragm that separates the potable water from the pre-pressurised gas chamber, ensuring corrosion-resistant operation. It is suitable for installation on boilers, water heaters and circulation systems where maintaining stable pressure and preventing overpressure events are required. The product is rated for operating pressures of up to 2.5/8 bar and operates across a temperature range from -10 °C to 100 °C.
Advantages
The diaphragm design provides reliable separation between water and gas, reducing the risk of corrosion and prolonging service life compared with non-diaphragm vessels. Its 18 L nominal capacity balances compact dimensions with sufficient volume to accommodate thermal expansion in domestic hot water systems. The specified pressure and temperature ratings allow for use with a wide range of residential boilers and water heaters. The vessel supports easier pressure management and reduces cycling of pumps and valves by absorbing pressure spikes and stabilising system pressure.
Suitable for
Domestic hot water systems (c.w.u.)
Boilers and water heaters
Circulation and distribution networks in residences
Pressure stabilisation and thermal expansion compensation
Key specifications
Nominal volume: 18 litres
Operating pressure range: up to 2.5/8 bar
Operating temperature range: -10 °C to 100 °C
Internal diaphragm separating fluid and gas
Intended for potable hot water applications
How to use
Install the expansion vessel according to system layout, mounting it on the cold or hot water line as specified by the system design and local regulations. Pre-charge the gas side to the recommended pressure for the system, taking into account static head and manufacturer guidelines. Connect the vessel using appropriate fittings and support it to avoid stress on pipework. After installation, check for leaks, verify pre-charge pressure and monitor system pressure during initial operation to ensure correct integration.
Usage recommendations
Ensure the pre-charge pressure is adjusted to match the static pressure of the installation; periodically inspect the diaphragm for integrity and check the vessel’s pre-charge every 6–12 months. Avoid exposure to freezing conditions beyond the specified limits and follow local plumbing codes for safe and compliant installation.

## FAQ

### How much does the CIMM ACS 18 L diaphragm vessel cost, and is it available for purchase?

The price is 43.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 186 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 07.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All CIMM products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized CIMM service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

https://aio.lv/img/cache/product/12064609/67549945_large.webp