Heating & Water
Roller Team Motorhome Water System: The Accumulator Guide
A practical guide to smoother water pressure, quieter pump operation, and better day-to-day comfort in your Roller Team motorhome.
What is an Accumulator?
A motorhome accumulator, also called a water accumulator or pressure accumulator, maintains a steady, consistent water pressure within your plumbing system.
It stores and releases water under pressure to ensure a smooth, uniform flow when using taps or appliances.
Why owners add one
- Steadier water pressure
- Reduced pulsing at taps
- Quieter pump operation
- Less wear on the pump
A valuable upgrade for owners who want a smoother and more controlled water system.
How It Works
Inline system view
This image shows how the accumulator sits inline with the motorhome water system, between the pump and the plumbing lines, helping smooth out pressure changes before water reaches taps, the shower, or the toilet.
Water pump function
Most motorhomes use a water pump to draw water from the freshwater tank and pressurize it through the plumbing lines.
The problem
Without an accumulator, water pressure varies as the pump cycles on and off, leading to surging water or uneven flow at faucets.
The solution
Positioned directly between the water pump and the rest of the plumbing, the accumulator is a small air-filled tank that acts as a cushion to absorb and store pressure.
Smooth flow delivery
When a tap, shower, or toilet is opened, water draws from the accumulator tank first, preventing sudden pressure drops and delivering a steady, constant flow.
Key Advantages & Benefits
Reduced Pulsing
Minimizes water surging and pulsing during use, making tasks like showering or washing dishes much more comfortable.
Benefit: smoother flow at taps and a more consistent feel when using onboard water.
Pump Longevity
Reduces wear and tear on the water pump by cutting down the frequency of its cycling.
Benefit: fewer start-stop cycles can help extend pump life over time.
Everyday Comfort
Smoother water delivery makes everyday washing, rinsing, and shower use feel more controlled and consistent.
Benefit: a quieter and more refined experience when living in your motorhome.
Pros & Cons Comparison
Advantages (Pros)
- Constant Water Pressure: Eliminates hot/cold fluctuations and uneven flow.
- Quieter Operation: Lowers noise levels by reducing constant pump cycling.
- Longer Pump Life: Decreases wear and tear from frequent start/stop cycles.
Considerations (Cons)
- Space & Installation: Requires physical space in the plumbing layout and careful installation to avoid leaks.
- Additional Cost: Involves an upfront investment over a standard water setup.
- Maintenance: May require periodic air pressure checks, leak inspections, or component upkeep.
- Limited Capacity: Finite storage means heavy, continuous water usage can still trigger pump cycling.
Two Typical Examples of Motorhome Accumulators That Work Well
These two commonly used accumulator tanks are good examples of the type of upgrade that suits many Roller Team motorhome water systems. Both are designed to smooth water flow, reduce pump pulsing, and improve day-to-day comfort when using taps, showers, and onboard appliances.
Fiamma A20 Expansion Tank
The Fiamma A20 is a compact and widely used motorhome accumulator designed to stabilize water pressure and reduce the pulsing effect often felt in smaller onboard plumbing systems. It is a practical choice for owners who want a smoother water supply without a complicated installation.
Key Benefits & Features
- Helps deliver a more even flow at taps and showers.
- Reduces pump cycling and the associated noise inside the motorhome.
- Compact design makes it easier to fit into tighter plumbing spaces.
- Can help extend pump life by reducing repeated start-stop operation.
Shurflo Expansion Tank 182-200
The Shurflo 182-200 is another well-regarded accumulator option, known for working effectively with common 12V motorhome pump systems. It is often chosen where owners want more consistent pressure delivery and a reduction in vibration and water hammer through the pipework.
Key Benefits & Features
- Supports smoother pressure delivery across the motorhome water system.
- Helps reduce vibration, pulsing, and sudden pressure changes.
- Pairs well with many standard motorhome water pumps.
- Useful for improving comfort during regular showering and washing-up use.
Understanding Water Accumulators: The Complete Guide for Your Home Plumbing System
While this guide focuses on Roller Team motorhomes, the same core principles also apply to many home and leisure plumbing systems. A water accumulator helps stabilize pressure, smooth out flow, and reduce the stop-start cycling that can make taps, showers, and appliances feel inconsistent.
In a motorhome, that means a more comfortable onboard experience. In a wider plumbing context, it also highlights why accumulators are often seen as a worthwhile upgrade where pressure fluctuations, noise, or pump wear are common concerns.
What is a Water Accumulator?
A water accumulator is a pressure-balancing tank fitted into a plumbing system to store water under pressure and release it in a more controlled way. In practical terms, it acts as a cushion between the pump and the outlets, helping maintain a steadier flow when a tap, shower, or appliance is in use.
Most units use an internal air chamber or diaphragm. As pressure builds, the accumulator absorbs some of that force. When water is needed, it releases pressure back into the system, reducing pulsing and helping the pump work more efficiently.
Expanded Pros and Cons
Pros
- Smoother water delivery at taps, showers, and toilets.
- Less pump noise and fewer abrupt pressure changes through the pipework.
- Reduced wear on the pump due to fewer rapid start-stop cycles.
- Improved comfort when washing up, showering, or using multiple outlets briefly.
- Can help reduce minor water wastage caused by spluttering or surging flow.
Cons
- Requires enough installation space close to the pump and pipework.
- Adds cost compared with leaving the standard pump-only setup unchanged.
- Needs correct pre-charge pressure and secure fittings to perform properly.
- May still allow pump cycling during heavy or continuous water demand.
- Periodic checks may be needed for leaks, pressure loss, or diaphragm condition.
How to Fit a Water Accumulator: Step-by-Step Instructions
Disclaimer: These steps are general guidance only and may not match every Roller Team model or every aftermarket accumulator. Always follow the manufacturer instructions for your specific pump, accumulator, and plumbing layout. If you are unsure, use a qualified technician to avoid leaks, electrical issues, or damage to the water system.
Tools and Materials Needed
- Water accumulator tank
- Suitable hose connectors or push-fit fittings
- Flexible hose or pipe to match your system
- Hose clips or clamps
- Screwdriver and basic hand tools
- Drill and fixings if mounting is required
- PTFE tape or sealing method recommended for the fittings
- Pressure gauge or pump for checking pre-charge if required
Installation Steps
- Turn off power and water supply. Switch off the 12V water pump, isolate the water supply if needed, and open a tap to release pressure from the system before starting work.
- Choose the right location. Fit the accumulator on the outlet side of the pump, as close to the pump as practical, while leaving enough room for secure mounting and future maintenance.
- Prepare the pipework. Identify the section of pipe or hose between the pump and the rest of the water system. Cut or disconnect the line cleanly and check that the fittings match the accumulator connections.
- Connect the accumulator. Attach the inlet and outlet fittings as required, tighten all connectors securely, and use the correct sealing method to help prevent leaks.
- Secure the unit and check pre-charge. Mount the accumulator firmly so it will not move during travel. If the model allows adjustment, confirm the pre-charge pressure is suitable for your pump setup.
- Test the system. Restore power to the pump, refill or repressurize the system, and run taps and the shower to check for leaks, smoother flow, and reduced pump cycling.
Pro tip: If the pump still chatters or cycles too often after installation, recheck the accumulator pre-charge, inspect for small leaks, and confirm the tank is fitted on the correct side of the pump.
Summary & Verdict
An accumulator is a valuable upgrade for a Roller Team motorhome water system, delivering smoother flow, less pump wear, and enhanced comfort.
Before purchasing, weigh the upfront costs, space requirements, and maintenance considerations against your specific travel and plumbing needs.