Useful tips

Can you recharge an expansion vessel?

Can you recharge an expansion vessel?

If the expansion vessel has been checked via the Schrader valve and the pressure is too low, it will require recharging or re-pressurising to the correct pressure. This can be done using a car foot pump or similar device.

What pressure should I set my expansion vessel to?

1 bar
Summary. Expansion vessels, also known as expansion tanks, keep the pressure in a combi boiler stable while water heats and cools. They are typically located inside the boiler casing. The typical pressure a boiler system should be set to is 1 bar.

How do I know if my expansion vessel is bad?

If you think the vessel has failed, unscrew the plastic cap from the pressurisation valve (it’s like a car tyre valve). Momentarily depress the pin in the valve to release a little pressure. If water comes out of the valve you have a definite expansion vessel fault.

Can you fit an expansion vessel on its side?

Expansion tanks can be installed horizontally. The recommendation that they are installed vertically is to reduce stress on the (normally copper) pipe, which should be adequately supported even if the tank is suspended vertically.

What happens if expansion tank pressure is too low?

If the precharge pressure is too low the tank may be excessivly full of water even before the thermal expansion takes place which may limit room for expansion, add additional weight to the tank, and, or, stress the tank bladder. These factors may reduce its service life.

Why does expansion vessel lose pressure?

Water expands and contracts according to whether it is hot or cold. The air in the pipes protects them from damage when the water expands as it heats up. The expansion vessel prevents the boiler pressure relief valve, releasing water to reduce pressure, simply from the expansion caused by the hot water.

What happens when the expansion tank fails?

What Happens if the Expansion / Compression Tank is Not Working? The loss of air cushion in the expansion / compression tank means that at each heating-on cycle the system pressure can be too high, causing the temperature/pressure relief valve to spill.

Why is my expansion vessel full of water?

Dripping water is one sign that a valve may be blocked. This can occur as a result of mineral deposits or other debris. Some older expansion tanks lack the internal bladders used in newer models. This component is what separates the water and air pressure.

Should expansion tank be on hot or cold side?

Although expansion tanks can be installed on the hot side, we strongly recommend they be installed on the cold line, downstream of the shutoff valve.

Which way do you fit an expansion vessel?

The Expansion Vessel must be fitted to the Return Side of the Central Heating System and in such a way that there can at no time be an obstruction between the vessel and the system.

What kind of diaphragm is in a boss expansion vessel?

Fitted with a fixed synthetic rubber membrane (SBR), secured by a clench type construction, they are approved and manufactured according to the Directive 97/23/CE, for heating and non-potable water. Fixed diaphragm design SBR rubber diaphragm (4 to 1000 litres)

What kind of water supply does a boss cylinder need?

The water supply must be of wholesome water quality (Fluid Category 1 as defined by the Water Regulations 1999). The BOSS™Unvented cylinder is to be used for the storage of wholesome water (max.250mg/l chloride). ELECTRICAL SUPPLY The BOSS™Unvented cylinder must be earthed. The BOSS™Unvented cylinder is suitable for AC supply only.

How big is a boss mains pressure cylinder?

BOSS™Unvented mains pressure cylinders offer outstanding performance, heat recovery and heat retention. The wide range from 120 litres to a massive 1000 litre capacity are available in either Direct, Indirect or Solar variants.

How big is a boss unvented gas cylinder?

The wide range from 120 litres to a massive 1000 litre capacity are available in either Direct, Indirect or Solar variants. BOSS™Unvented cylinders are supported by a 25 year warranty package which offers peace of mind and security (for full warranty terms see page 13).