How to Repressurise A Vokera Boiler: Step-by-Step Guide
A Vokera boiler needs the right pressure to heat your home and provide hot water properly. If the pressure drops too low, the boiler may stop working or show a fault code. In most cases, you can Repressurise A Vokera Boiler by using the filling loop to top up the system pressure. However, if the pressure keeps dropping, you may have a leak or faulty part that needs a Gas Safe registered engineer.
What Pressure Should a Vokera Boiler Be?
Most Vokera boilers work best when the pressure sits between 1.0 and 1.5 bar when the system is cold.
If the pressure drops below 1 bar, your boiler may struggle to work correctly. As a result, you may lose heating or hot water. However, the pressure should not rise too high either. If it gets close to 3 bar, the pressure relief valve may release water to protect the system.
Why Does a Vokera Boiler Lose Pressure?
A Vokera boiler can lose pressure for several reasons. Sometimes, it happens after bleeding radiators. Other times, it may happen because of a small leak, a faulty pressure relief valve, or an issue with the expansion vessel.
If the pressure only drops occasionally, topping it up may solve the problem. However, if it drops again quickly, the system needs proper inspection.
How to Check Vokera Boiler Pressure
You can check the pressure by looking at the pressure gauge on the front of the boiler or underneath the control panel.
The gauge usually shows the pressure in bar.
- Below 1 bar: pressure is too low
- Around 1.0 to 1.5 bar: normal pressure when cold
- Around 2 bar or above: pressure may be high
- Near 3 bar: pressure is too high and needs attention
Always check the pressure when the heating system is cold because a warm system can show a higher reading.
How to Repressurise A Vokera Boiler – Step-by-Step Process
Time needed: 5 minutes
Here is a simple step-by-step guide for repressurising most Vokera boilers.
- Check the Pressure Gauge
First, check the pressure gauge on your Vokera boiler. If the needle is below 1 bar, the system needs more pressure.
- Turn Off the Boiler
Next, turn off the boiler using the fused spur switch or boiler power switch. This is usually located near the boiler.
Do not remove the boiler cover or touch any internal parts. You only need to access the filling loop underneath the boiler. - Locate the Filling Loop
The filling loop connects your boiler system to the mains water supply. It is usually located underneath the boiler.
There are two common types:
External filling loop
This is usually a detachable silver braided hose.
Internal filling loop
This is built into the boiler and may use a key, lever, or built-in valve.
Check your Vokera boiler manual if you are unsure which type your model has. - Attach the External Filling Loop
If your boiler has an external filling loop, make sure both valves are closed before attaching it.
Then, connect the silver hose to both ends by hand. Make sure the washers are fitted correctly because they help prevent leaks.
Do not over-tighten the connections. Hand-tightening is usually enough. - Open the Valves Slowly
Open the first valve, then slowly open the second valve. You should hear water entering the system.
Watch the pressure gauge carefully while the pressure rises.
When the gauge reaches 1.0 to 1.5 bar, close both valves fully. - Remove the Filling Loop
If you used an external filling loop, remove it after closing the valves. Keep a towel or small container nearby because a little water may come out of the hose.
Then, refit the caps if your system has them. - Restart the Boiler
Turn the boiler back on and allow it to restart. This may take a few minutes.
After restarting, test the heating and hot water. If everything works normally and the pressure stays stable, the boiler has been repressurised successfully.
Common Reasons Your Vokera Boiler Keeps Losing Pressure
If your Vokera boiler keeps losing pressure, one of these issues may be the cause.
1. Leaks in the Heating System
Leaks can happen around radiators, pipe joints, valves, or boiler connections. Even a small leak can slowly reduce pressure over time.
Check for damp patches, water marks, or dripping around the heating system.
2. Faulty Pressure Relief Valve
The pressure relief valve, also called the PRV, protects the boiler when the pressure gets too high.
If the PRV becomes faulty or stuck open, it may release water and cause the pressure to drop.
3. Expansion Vessel Problem
The expansion vessel helps control pressure changes when the water heats up.
If the vessel loses its air charge or becomes damaged, the boiler pressure may rise too high and then drop again.
4. Recently Bled Radiators
Bleeding radiators removes trapped air from the system. However, it can also lower the boiler pressure.
If you recently bled your radiators, you may need to top up the boiler pressure afterwards.
5. Internal Boiler Leak
Some leaks happen inside the boiler. These can involve parts such as the pump, heat exchanger, seals, or valves.
You should not try to repair internal boiler parts yourself. A Gas Safe registered engineer should inspect the boiler safely.
Final Thoughts
Increasing pressure in a Vokera boiler is usually simple if you follow the correct steps. First, check the pressure gauge. Then, use the filling loop to raise the pressure to around 1.0 to 1.5 bar. After that, restart the boiler and monitor the gauge. However, if the pressure keeps dropping, do not keep topping it up. Instead, contact a Gas Safe registered engineer to find and repair the cause safely.
Frequently Asked Questions
The pressure gauge shows the current pressure of the system, the gauge should be set between 1 and 1.5 bar. When the appliance is operating the gauge may rise or fall slightly, this is quite normal. The minimum permissible level for the safe and efficient operation of the appliance is 0.5 bar.
Open up both valves so that they’re in line with the pipe to allow cold mains water into the system. You should be able to hear it. Wait for the water pressure to reach between 1 and 1.5 on the pressure gauge. Once it has, shut off both valves one after the other.
The filling loop is usually underneath the boiler. It may be an external silver braided hose or an internal filling loop built into the boiler.
A pressure reading around 2 bar can happen when the heating is running. However, if the pressure keeps rising or gets close to 3 bar, you should call an engineer.
Common causes include leaks, a faulty pressure relief valve, expansion vessel problems, or recent radiator bleeding. If the pressure drops quickly after topping up, the system needs checking.
