50 Litre Buffer Tank – Wall or Floor Mounted
50 Litre Buffer Tank
Our 50 Litre buffer tanks, which are available in a wall mounted or floor standing version for hot or cold water systems improves the efficiency of heat pumps and chillers or even reduce the start and stop cycles of a gas or oil traditional boiler. They also act as a hydraulic separator, separating the primary and secondary circuits of the heating or cooling system.
Generally, a buffer tank is typically used for storing energy (thermal energy storage) via hot or cold water in conjunction with a heat pump powered by renewable energy or a boiler.
They can improve response times, the coefficient of performance (COP), and the operating efficiency and lifespan of the heat pump by storing additional water volume and acting as a hydraulic separator that separates the primary and secondary circuits.
Our 50 litre buffer vessel benefits from Class “A” rated insulation for minimal heat loss and energy efficiency and is created expressly for use with heat pump installations. They are specifically designed to provide a stored additional volume of warm or heated water that helps to minimise heat pump compressor short cycling and makes the heating system in the property more energy efficient and increases the life span of the heat pump, as the buffer function reduces the heat pump on/off cycles.
Benefits of our 50L thermal storage buffer vessel
By hydraulically separating the flow and return heating circuits in the system to account for variations in flow rate and pressure drops, the buffer vessel hydraulically separates the heating systems, i.e., the heat pump from the heating circuit.
This improves the heat pump’s performance and efficiency while protecting the heat pump from erratic flows, thus increasing the heat pump’s lifespan. Additionally, we add system volume for defrosts and stability of the heat pump’s operation by separating primary and secondary circuits as a hydraulic separator.
50 Ltr Heat Pump Buffer Tanks – “A” class rated with premium polyurethane foam insulation
Our 50L buffer tank range has a class-leading energy “A” rating for its insulation values for minimal heat loss, which means these buffer tanks keep the heating hot water temperature higher for longer and, as a result, increase response times to demands from the heating system, whilst reducing the heat pump’s short cycling with this small buffer tank.
ErP “A”-rated buffer tank 50 litres in volume and 304 stainless steel construction.Floor or wall mounted buffer.
The tank provides a reserve of heat needed to defrost the outdoor unit of air-to-water heat pumps without drawing heat from the home’s radiators. The benefits include a buffer that stores additional volume and also serves as a hydraulic separator.
Stainless steel construction justification
To us it just makes sense; you spend many thousands of pounds to purchase an air source heat pump, so why would you install an inferior carbon steel buffer tank? Why choose a stainless steel buffer tank when it is only marginally pricier and ensures trouble-free operation of the heating system? Why wouldn’t you do everything to protect your heat pump?.
The issue with carbon steel buffer vessels or tanks
- Internal corrosion of the buffer tank is the biggest concern. Mild steel and carbon steel rusts when exposed to water and oxygen, especially if the system water isn’t properly treated
- Magnetite and sludge formation – rust particles circulate through the system, fouling heat exchangers, pumps, and valves
- Pitting corrosion can develop internally, eventually leading to pinhole leaks in the carbon or mild steel.
- Requires strict inhibitor management and regular water quality testing
Heat pump-specific concerns of carbon steel buffers
- Heat pumps are particularly sensitive to poor water quality — dirty water can void manufacturer warranties
- Low flow temperatures mean corrosion byproducts take longer to show up but accumulate silently
- Magnetite damages the heat pump’s plate heat exchanger, which is expensive to replace
Maintenance Burden
- Inhibitor concentration must be checked at least annually
- The system should have a magnetic filter fitted and cleaned regularly
- External surfaces can also rust if the carbon steel buffer tank isn’t properly painted or coated.
Lifespan
- Typically, they have a shorter lifespan than stainless steel buffer tanks if water treatment is neglected.
- Internal lining (if present in the carbon steel buffer tank) can degrade over time, especially with repeated thermal cycling.
Conclusion
Carbon steel or mild steel buffer tanks can work well, but they demand disciplined water treatment and filtration. In heat pump systems, in particular, many HVAC installers now prefer stainless steel buffer tanks.
Stainless steel buffer tank benefits
The benefits of stainless buffer tanks
- Naturally corrosion resistant — no internal lining or coating required
- Won’t rust or pit under normal operating conditions
- Much more tolerant of variations in inhibitor concentration than carbon steel and mild steel buffer tanks
- Significantly reduces magnetite and sludge generation, protecting the whole system
Conclusion
The higher upfront cost of stainless steel is almost always justified in a heat pump HVAC installation. The savings in maintenance, warranty protection, reliability and system longevity make it a preferred choice for quality installations.
50 litre Floor or wall mounted buffer tank option
We produce one 50 Litre volume buffer tank that can be either wall mounted or a floor mounted buffer tank depending on your site requirements. Our 50 litre unit does both applications with easy installation, with the buffer storing additional volume for the heat pump system, for example.
Wall mounted or floor standing 50l buffer vessel or tank from Flexiheat UK
As the units have a wall mounting bracket built in for wall installation, people sometimes refer to them as hanging energy buffer tanks in this configuration.
4 x Side connections (2 connections on each side) 180 degrees in orientation Free-standing & Wall-mounted model
Specifications and dimensions:
Height: 636 mm
Inner tank: diameter Ø350 mm, 1 mm stainless steel, 304 grade
Outer shell: diameter Ø 420 mm
Insulation: 35 mm premium polyurethane foam insulation
4 x connection: Female 1″
1 x connection: Female 1/2″ (sensor tube or temperature gauge connection)
1 x vent: Female 3/4″ (Drain point)
Weight: 20 kg
Full buffer vessel/tank technical detail
50 litre stainless steel buffer tank dimension and connection detail
| Connections | All connections are female BSP | 50 Litre capacity | |
|---|---|---|---|
| H | Height | 636 mm | |
| ØD | Outer diameter | 420 mm | |
| Ød | Inner diameter | 350 mm | |
| H | DN 14 | G 1/2″ | Pressure relief valve or air vent connection for venting |
| A | DN 4 | G 1″ | Connection (Inlet/Outlet) |
| B | DN 3 | G 1″ | Connection (Inlet/Outlet) |
| E | DN 7 | G 1/2″ | Sensor immersion pocket (1) (12.7mm) |
| E | DN 8 | G 1″ | Connection (Inlet/Outlet) |
| F | DN 9 | G 1″ | Connection (Inlet/Outlet) |
| G | DN 2 | G 1/2″ | Drain port (drainage port) |
Construction, insulation and pressure ratings
| Inner tank material | AISI 304 stainless steel |
| Insulation material | Polyurethane rigid foam, CFC free — 35 mm |
| Buffer tank casing material | Frosted metal finish, colour RAL 7030 |
| Max. static working pressure (tank) | 6 bar |
| Max. working temperature (tank) | 95°C |
| Weight (Empty buffer tank ) | 15 kg |
These buffer tanks are suitable for a water glycol mix of up to 50% in cold water systems, as these buffer tanks are intended for storing heat and/or cold in cooperation with a heat pump, be it an air-source or ground source heat pumps. They are rated at 6 bar, unlike many competitors on the UK market, which are only rated at 4 bar.
8 connection 50 Litre buffer option
We also do a 50 Litre buffer, again in stainless steel, and for hot or cold water but with 8 main connections so you can integrate another heat source to the buffer, i.e., a heat pump and a boiler or even solar thermal systems. As per the 4 connection units, they are a floor or wall installation unit.
8 connection 50 litre buffer vessel or tank in stainless steel – wall or floor mounted
These eight connection 50L buffer tanks are also ErP “A” rated for minimal heat loss, with our premium polyurethane foam insulation, and increase operating efficiency by reducing compressor pump short cycling of the heat pump and acting as a hydraulic separator.
50 Litre 8 connection buffer tank version – The buffer tank can be integrated with multiple circuits and heat sources due to its multiple inlet and outlet ports. Floor or wall mounted buffer tank from Flexiheat UK
If you require a domestic hot water buffer tank, then these need to be duplex stainless steel; due to the chlorinated water, these are detailed on this webpage – Stainless steel water storage tanks
Contact us for your hot and cold water buffer tank 50 Litre capacity requirements
If you require further information, questions, product availability, check stock levels, get quotes, find prices or order our 50 Litre buffer tank designed for heat pumps (which has the main functions of improving the operating efficiency of heat pumps by reducing compressor pump short cycling, as the buffer function reduces the heat pump’s on/off cycles for hot or cold water production) and acting as a hydraulic separator.
The hydraulic separation function of a buffer tank keeps the heat pump flow rates separate from those of the secondary circuits of the heating system, ensuring that the heat pump receives adequate flow at all times.
Please feel free to contact our sales experts team on this number, 01202 822221 or use our email contact form via the contact tab above to email us.
Flexiheat UK