PulsaCoil A Class Common Faults
The PulsaCoil A Class is a direct electric thermal store, rather than a conventional hot water cylinder.
The difference between a conventional hot water cylinder and PulsaCoil A Class thermal store is that they both hold hot water and are both heated via immersion heaters this is where the similarity ends.
The PulsaCoil A Class thermal store is filled with hot water that never changes. The heat stored in the PulsaCoil A Class is used to heat the tap water using a plate heat exchanger, allowing the hot tap water to be delivered at mains pressure. A conventional system works on gravity feed, with this system you would experience a lower water pressure.
PulsaCoil A Class transfer heat into the cold tap water using a pump and a plate heat exchanger. A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The cold and hot water are separated by a solid wall, they never mix,
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PulsaCoil A Class Common Faults associated with the PulsaCoil A Class breakdowns are:
Lack of water in the thermal store
Circuit board failure
Persistent tripping of the overheat protection thermostat
Immersion heater element failure
Immersion heater leaking
External Economy Seven time clock failure
Water scale-contaminated plate heat exchanger
PulsaCoil A Class Common Faults associated with PulsaCoil A Class and what it could be relating to
- No electricity supply to PulsaCoil A Class system – this does not allow the PSC (pump speed control) or any other internal components to work inside the PulsaCoil A Class. It does not allow a supply to go through to the immersion elements.
- No power supply to PulsaCoil A Class immersion elements – this does not allow the immersion element to heat up, so this does not allow the water in the tank to heat up, resulting in no hot water in the storage tank.
- Main thermostat cut out on PulsaCoil A Class – this cuts the relay off not allowing a power supply to go to the two immersion elements inside the PulsaCoil A Class system. Therefore the immersion elements do not heat up the water inside the storage tank.
- Immersion elements thermostats cut out –this does not allow a power supply to pass through the thermostat into the immersion element. Therefore the water inside the tank does not heat up. Due to there being a thermostat per immersion element it is very rare both become faulty at once or cut out at the same time. We have realised that most customer are only using 1 immersion element when needed and never knew the additional immersion element thermostat was faulty to begin with.
- PulsaCoil A Class immersion elements faulty – Immersion elements on PulsaCoil A Class do become faulty. This can cause an immersion element not to heat water inside thermal store. Usually it is rare for both immersion elements to become faulty at the same time but most customers do not know if there second immersion element was faulty to begin with prior.
- Relay has become faulty – the relay when faulty will not allow power to pass through it into the immersion elements thermostat and then to the immersion element. The relay controls the supply to both immersion elements and if faulty won’t allow power to either immersion elements.
- PSC (pump speed control) failure – if the pump speed control if not working correctly will not supply the PulsaCoil A Class pump with power. This will then not allow hot water to be pumped around an installation at all.
- Store sensor failure – This will stop the power supply to a PulsaCoil A Class pump and not allow hot water to be pumped around an installation. It does this by direct connection to the PSC (pump speed control).
- Lack of hot water or not enough hot water – Hot water sensor – This will not allow power to the PulsaCoil A Class pump and not allow hot water to be pumped around an installation. It does this by connecting to the PSC (pump speed control).
- Plated heat exchange calcium build up – this does not allow hot water to be exchanged at the plated heat exchanger and due to this the pump cannot pump hot water around the system.
PulsaCoil A Class Common Faults associated with no hot water when using ‘Off Peak’ but booster works
- ‘Off Peak’ supply faulty – If no supply is coming to the ‘Off Peak’ immersion element, it cannot heat the water inside the storage tank overnight. So no hot water is present for the pump to pump around an installation.
- ‘Off Peak’ switched fused spur faulty – spurs are an isolation point for supplies to immersion elements. If a spur becomes faulty, the supply to the immersion element is not present and the water inside the tank is not heated up correctly.
- ‘Off Peak’ element faulty – a faulty immersion element does not heat up water inside a storage tank overnight. No hot water will be present the following day for a pump to pump around an installation.
- ‘Off Peak’ immersion element thermostat faulty – when a thermostat becomes faulty it prevent the supply of power to an immersion element. The immersion element then cannot heat the water inside the storage tank overnight.
- ‘Off Peak’ cables damaged – damaged cables can stop supplying power to ‘Off Peak’ immersion elements, they can also become a fire hazard.
PulsaCoil A Class Common Faults associated with no hot water on booster but ‘Off Peak’ works
- Booster supply faulty – if no supply is coming to the booster immersion element, it cannot start heating the water inside the storage tank immediately.
- Booster switched fused spur faulty– spurs are an isolation point for supplies to immersion elements. If a spur becomes faulty, the supply from the booster switch to the immersion element is not present and the water inside the tank is not heated up.
- Booster immersion element faulty – a faulty immersion element does not heat up water inside a storage tank on demand.
- Booster immersion element thermostat faulty– when a thermostat becomes faulty it prevent the supply of power to an immersion element. The immersion element then cannot heat the water inside the storage tank instantaneously.
- Booster cables damaged– damaged cables can stop supplying power to booster immersion elements, they can also become a fire hazard if not attended to.
PulsaCoil A Class Common Faults associated with fluctuation in temperature
- PSC (pump speed control) faulty – this then does not send a 230v power supply to the pump instructing it to pump hot water around an installation.
- Store sensor faulty – this tells the PSC (pump speed control) to send a 230v supply to the pump so it can pump hot water around the installation. When faulty it does not tell the PSC (pump speed control) to do this.
- Hot water sensor faulty – this instructs the PSC (pump speed control) to send the correct power supply to the pump. Then the pump pumps hot water around the installation. When faulty it does not send this instruction.
PulsaCoil A Class Common Faults associated with temperature dropping over time
- Plated heat exchanger contaminated with calcium build up – when this occurs it slowly starts restricting hot water that should be pumped around an installation.
- Store sensor becoming faulty – this does not give the right instructions to a PSC (pump speed control) to pump hot water around an installation.
- Hot water sensor becoming faulty – this does not give the right instructions to the PSC (pump speed control) and then the pump is not pumping hot water around an installation.
- PSC (pump speed control) faulty – this then may only send a limited amount of voltage to a pump. This then does not allow the pump to circulate a sufficient amount of hot water. Over a period of time this will deteriorate.
PulsaCoil A Class Common Faults associated with water leaking from PulsaCoil A Class
- Thermostat pocket rusted
- Thermal storage tank inside system rusted
- Pipe work rusted
- Pipe burst
These all occur due to wear and tear. It is usual for the original immersion element inside a PulsaCoil A Class pocket to start leaking.
PulsaCoil A Class Common Faults associated with inexperienced engineer mistakes and misdiagnoses
- Incorrect testing of immersion element – untrained engineers use only a continuity buzzer to check immersion elements. This is incorrect as even a faulty immersion element can show a closed circuit. An ohms resistance is required to establish if an immersion element is faulty.
- Checking the pump incorrectly – a certain voltage is required at a PulsaCoil A Class pump, if that voltage is present and the engineer is still not getting hot water and he tells you the pump is faulty, he could be wrong. This does not necessarily mean the pump is faulty. This can be correctly inspected in other ways to ensure it is the pump that is faulty.
- Not knowing how to test the relay – just because the relay is not allowing power to pass does not mean the relay is faulty. The relay is connected to other components that tell it to switch on or off. This can be inspected by bypassing a component safely.
- PSC faulty or not – most inexperienced engineers believe if the pump is working, the immersion elements are buzzing a continuity the PulsaCoil A Class PSC must be faulty. This is not always true, certain tests should be done prior to coming to that conclusion as it is the most expensive part second to the entire system.
- Heat sink compound – this not applied correctly on a sensor will not allow it to work correctly giving you a fluctuation in temperature or no hot water. Make sure the engineer applies this on the correct sensor.
- Water damages – if the mains water supply is not isolated correctly and the water pressure reduced, this can cause plenty of water to leak out of the system causing damages to your property.
- Not resetting thermostats – Some engineers believe if a thermostat is not showing continuity it must be faulty. This is not always true, sometimes a simple reset can fix the problem, if the problem persists then we would recommend changing it. Resetting the thermostat is simple if you know what you are doing but can be hard and dangerous if you don’t.
- Not check supply – this may sound simple but ‘Off Peak’ supplies only come on at night. Different types of test will have to be done instead of your standard voltage test. This can save you money as the ‘Off Peak’ supply is your network distributors responsibility.
Gledhill PulsaCoil A Class boilers are backed by a comprehensive after-sales service provided by MK Group Limited.
MK Group service and support Gledhill PulsaCoil A Class products all year round. Their Engineers have an exceptional understanding of the Pulsacoil range of hot water solutions because they specialize only in the service and repair of PulsaCoil products.
Learn more about MK Group by visiting their website.
All parts and spares required for your PulsaCoil A Class is available from MK Group spares.
Learn more about MK Group spares by visiting their website.