Salamander AccuBoost 330L Unpumped Accumulator | ACC-330-TNK

Description

The Salamander AccuBoost ACC-330-TNK is a 330-litre unpumped accumulator vessel that stores mains cold water under pressure and releases it when an outlet opens, adding up to 24 L/min on top of the incoming mains flow. It suits mains-fed properties with static pressure above 2.0 bar and natural flow above 12 L/min where demand still outstrips supply at peak times, typically on combination boilers and unvented hot water cylinders.

Built from lightweight composite, the vessel holds 150.5 litres of stored water, is rated to 8.6 bar and is WRAS approved. Being unpumped it needs no electrical connection, runs at just 30.9 dBA filling and 37.4 dBA emptying and carries a 3-year manufacturer's warranty. Further vessels can be linked to increase stored volume.

330 L

Vessel size

150.5 L

Stored water

+24 L/min

Added to mains flow

8.6 bar

Max operating pressure

3/4" BSP

Male connection

3 years

Manufacturer warranty

Key notes before you specify

Unpumped or pumped?

Unpumped suits mains static pressure of 2.0 bar or more and natural flow above 12 L/min. If the mains is below 2.0 bar, below 12 L/min, or you do not know, choose the pumped AccuBoost 330L instead. Once the stored water is used, flow returns to the natural mains rate until the vessel refills.

Installation and safety

Install by a competent person in line with the Water Supply (Water Fittings) Regulations and BS EN 806. Fit a double check valve and pressure reducing valve after the stopcock, and never let system pressure exceed 8.6 bar. On unvented cylinders, set the AccuBoost pressure reducing valve below the cylinder's pressure reducing valve and safety valve. Cold mains water only: never fit to hot water pipework. Water temperature must stay between 4°C and 35°C, with frost and heat protection where needed.

Set the air precharge correctly

Keep the air precharge about 1.5 bar below the mains static pressure and never below 0.5 bar. Check it with the water supply off and the vessel empty, using the Schrader valve under the top cover. Leave 100 mm clear above the vessel for access.

Key features

1

+24 L/min on top of mains flow

Supplements the incoming supply with 24 L/min of extra flow (excluding natural mains flow) so showers and taps can run together.

2

150.5 L of stored water

A 330 L vessel shares its volume between air and water, storing up to 150.5 litres depending on precharge, with a refill time of about 30 minutes.

3

Lightweight composite build

35.5 kg empty and corrosion resistant, standing 1407 mm tall on a 621 x 621 mm footprint.

4

WRAS approved, 3-year warranty

WRAS approval 250402011 and a 3-year manufacturer's warranty when registered within 15 days of purchase.

5

Quiet in operation

Rated at 30.9 dBA when filling and 37.4 dBA when emptying. No pump, no motor and no electrical supply.

6

Modular and ready to install

Supplied as one unit ready to install. Link multiple vessels for more stored volume, and use the Schrader valve to adjust precharge.

Technical specification

Capacity and performance

Vessel size

330 litres

Maximum stored water

150.5 litres

Added flow rate

24 L/min (not including natural mains flow)

Approx. fill time

30 minutes

Minimum mains static pressure

2.0 bar

Pressure, temperature and connection

Maximum operating pressure

8.6 bar (860 kPa)

Water temperature

4°C to 35°C, cold mains water only

Connection

3/4" male BSP

Dimensions and weight

Height

1407 mm

Width x depth

621 x 621 mm

Empty weight

35.5 kg

Filled weight

186 kg

Maximum weight

336.5 kg

Noise

Noise when filling

30.9 dBA

Noise when emptying

37.4 dBA

Approvals and identification

WRAS approval

250402011

Manufacturer warranty

3 years (register within 15 days of purchase)

Manufacturer part number

ACC-330-TNK

Precharge and pressure reducing valve settings

Mains static pressure

Air precharge

Max PRV setting

2.0 bar

0.5 bar (7.25 psi)

2.5 bar

2.5 bar

1.0 bar (14.5 psi)

3.0 bar

3.0 bar

1.5 bar (21.75 psi)

3.5 bar

3.5 bar

2.0 bar (29.0 psi)

4.0 bar

4.0 bar

2.5 bar (36.25 psi)

4.5 bar

Frequently asked questions

Is the unpumped AccuBoost 330L right for my property?

It is designed for mains-fed systems with static pressure of 2.0 bar or above and natural flow above 12 L/min where extra flow is needed, for example when several outlets run at once on a combi boiler or unvented cylinder. If you are unsure of the mains figures, measure them first or choose the pumped model.

How much extra flow does it give, and for how long?

It adds up to 24 L/min on top of the natural mains flow while stored water lasts. The vessel stores up to 150.5 litres, depending on precharge, then flow returns to the natural mains rate. Refill takes about 30 minutes, and performance improves when the mains flow is higher.

How do I set the air precharge?

Measure the mains static pressure with no outlets running, then set the vessel precharge about 1.5 bar lower (never below 0.5 bar) using the Schrader valve. For example, 3.0 bar static pressure needs 1.5 bar precharge and a pressure reducing valve set no higher than 3.5 bar. Do this with the water off and the vessel empty.

Can it be installed horizontally or on any floor?

No. It must stand vertically on a smooth, flat, level surface that supports the whole base and the maximum weight of 336.5 kg. The location must be dry and frost free, with easy access for isolation valves and 100 mm clear above the vessel.

Which valves and fittings are needed?

Fit a double check valve and pressure reducing valve after the stopcock. A maintenance bypass with full-bore isolating valves and an inline strainer before the vessel are recommended. Do not use jointing compound, hemp or steel wool, and keep solder flux away from the vessel.

Can I link more than one vessel, and what maintenance is needed?

Yes, several unpumped vessels can be linked with the manufacturer's connector kit, with the same precharge set in each. For maintenance, clean the inline strainer at least once a year and check the air precharge.

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