domestic Services

Unvented cylinder Get mains pressure hot water all day

unvented cylinder

domestic Services

Unvented cylinder Get mains pressure hot water all day

Never Worry About Being Without Hot Water

While vented hot water heaters might be the most popular in the UK, unvented hot water heaters are chosen by some builders and homeowners today. These systems are very different from vented hot water heaters, and should only be installed, maintained and repaired by registered experts who are knowledgeable and experienced.

At Pace Heating & Plumbing, we specialise in unvented hot water heaters and related systems, including discharge pipework. We offer industry-leading service and maintenance solutions to clients throughout London and within the M25. Our experts carry a wide range of replacement parts on their vans, and we stock even more in our shop to ensure that we’re able to get your hot water back on in record time.

Emergency Unvented Hotwater Services

Our Experienced plumbers can help you with unvented hot water cylinder repair or replacement


What's All the Fuss About

As mentioned above, the unvented system draws water from the mains. It then heats the water in one of two ways, depending on whether it is direct or indirect.

An indirectly heated system (which is the most common) gets heat from an external source, often in the form of a gas boiler, air source heat pump or solar panels. The hot water then travels through a copper coil in the hot water cylinder, heating the surrounding water without actually mixing with it.

A direct cylinder system uses an internal element, often in the form of an immersion heater. This is required for properties which have no access to gas, such as off-grid homes.

What are the advantages of unvented hot water cylinders?

  • The pressure of the hot water coming out of taps and showers is greater in an unvented system. This is because water is drawn from the cold-water mains supply, as opposed to from a water tank (which is often found in the loft). Higher pressure becomes especially important when there are multiple bathrooms which may be running hot water from several taps at once. An effective unvented cylinder, could make all the difference when it comes to enjoying nice, hot, and pressurised showers.
  • The benefit of using an unvented cylinder is that a cold-water tank in the property is not required, meaning homes with limited space do not need to lose precious storage. Removing the need for a tank also prevents potential freezing issues during long cold snaps, such as 2018’s Beast from the East.
  • There is a reduced risk of contamination because it is a closed system, with less chance for foreign materials to enter the system and ultimately cause potential damage.


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4 Causes of unvented cylinder failure

Here are a few things that could be causing your unvented hot water cylinder form not working:

No Heated Water

If you open the hot tap and tepid or even cold water comes out, it could be related to a very wide range of problems. For instance, there could be a problem with the electrical supply to the hot water heater, such as a blown fuse or something similar. It could also be related to the volume of hot water used already, or it could be related to damage to one or both of the heating elements in the unvented hot water heater.

No Water Flow

We offer experienced assistance no matter what has happened to your hot water supply. In some instances, you might open the hot tap and find that no water comes out at all. In this instance, there are many potential problems, including an issue with the mains themselves.

Noisy hot water pipes

Have you noticed your pipes getting noisier? Then that’s a strong sign that something is wrong. And it could be one of a few things: high water pressure, clogged pipes or loose fittings.

High water pressure can cause a lot of damage to the pipes around your home. And this can lead to leaks. It can also wear out taps, meaning that you’ll have to replace them much sooner.

The first thing you’ll want to do if you suspect high water pressure is contact your supplier. Following that, a Pace plumber can fit a pressure regulator valve. This will monitor the water pressure in your home and make sure that it doesn’t get too high.

Check your timer controller

Another factor to consider before calling a Pace engineer is to check your timer. This may have been affected by the clocks changing, power supply, back-up batteries failing or even somebody altering the settings without you knowing.

It should be easy to see at the timer control panel if the boiler is currently active for hot water. If you are not sure, check your timer manual.

A registered plumbing professional from PACE can diagnose and fix a no hot water problem because we know every second counts in a not hot water emergency, we’ll tackle your problem quickly and efficiently.



Prevention & Troubleshooting

However, while we’re more than happy to provide any help needed to troubleshoot, repair or replace a hot water heater, there are a few quick and easy steps you can take on your own to save time and money. These checks are safe for the average homeowner to carry out, providing you bear a few basics in mind relating to electrical safety. The self-help checks detailed within this guide are relatively basic,
With that being said, if you’re unsure how to complete these checks safely, or have any qualms about your ability to complete them yourself, call for assistance or book a call-out with a Pace engineer.

No Hot Water

If you open the hot tap and tepid or even cold water comes out, it could be related to a very wide range of problems. For instance, there could be a problem with the electrical supply to the hot water heater, such as a blown fuse or something similar. It could also be related to the volume of hot water used already, or it could be related to damage to one or both of the heating elements in the unvented hot water heater.

Check the Circuit Breaker

Locate your breaker box and find the mini-circuit breaker for the unvented cylinder water heater. Is it in the on or off position? Note that some water heaters actually have two circuit breakers. One operates the boost immersion heater and the other operates the main immersion heater at the bottom of the cylinder. If the breaker is in the off position, turn it to on. If it will not remain in the on position, do not attempt to force it. Leave it in the off position and call Pace for professional help. This means there is a serious electrical fault, possibly caused by a damaged immersion heater. If the breaker stays in the on position, allow the unit to heat the water and check the flow at the tap.

Check the Water Heating

Is the water heater timer controller or programmer switched on and set correctly? It may have been inadvertently knocked and turned the hot water system off. Alternatively, summer settings might not be adequate for wintertime temperatures when incoming water from the mains is much colder and requires more time to heat.

Check the Fuse

Has the water heater fuse blown? There is a 13-amp fuse located in the water heater fuse spur (boxes). Check this and replace it if needed. If the replacement fuse also blows, there may be a loose wire causing a short circuit., call Pace for unvented cylinder water heater repairs.

Check Water Usage

Another possible cause of no hot water is higher than normal hot water use. Has the household been taking more baths or longer showers than normal? Hot water cylinders vary in capacity from 120 litres upward. The average cylinder holds between 160 and 210 litres. The problem might not be a water heater fault’s simple high demand might be the culprit. You can address this in the short-term by pressing the boost function. If the higher demand is more permanent in nature, you can adjust the time clock on the water heater to suit your new usage situation.

If the steps listed above do not help, you’ll need to call Pace Heating & Plumbing for professional assistance. If you need assistance with any hot water heater repairs, to schedule hot water heater maintenance, or to install a new hot water heater, call Pace at 0207-183-2727

Water dripping from the plastic pipe

If you have water dripping from the Tundish which is the overflow pipe the runs from the unvented cylinder to the water waste and to the outside. Then you have a problem, in most cases, call Pace for unvented cylinder water heater repairs.

Not getting enough hot water through from my tap

If you’re not getting enough hot water or no water at all, check the other hot and cold water taps in your home if you are having the problem only the hot water taps then the unvented cylinder water stopcock has been shut off or the cylinder inline filter is blocked.

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Scheduling your Appointment

Pace Heating & Plumbing is dedicated to bringing peace of mind to you year-round. All our engineers are gas safe registered. Call 0207-183-2727 if you are not ready to talk now fill out your contact information and a dedicated Home Advisor will work with you to customize a solution for your home and family needs

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