When experiencing issues with your central heating system, it may seem like your radiators aren’t getting as hot as they should be. Or, perhaps, you’re hearing strange noises coming from your heating pump. Central heating pump problems are one of the most common issues that homeowners face when it comes to their heating systems.
While central heating pumps are generally reliable, like any mechanical device, they can develop faults over time. Some of these problems may be minor and easy to fix, while others can be more complex and require the help of a professional. Read on to explore some of the most common central heating pump problems and their fixes.
What is a Central Heating Pump?
A central heating pump is a device that is typically installed in a central heating system to circulate hot water around the system. It is designed to help distribute hot water from the boiler to and around the radiators or underfloor heating system and then return cooler water back to the boiler for reheating.
The pump uses an electric motor to drive an impeller, which spins rapidly inside the pump housing. As the impeller rotates, it creates a water flow through the pump, pushing the hot water through the heating system.
Central heating pumps are essential for most modern heating systems, as they help to ensure that heat is distributed evenly throughout the home. They are typically designed to be energy-efficient and durable, and they can be controlled using a thermostat or other heating controls to ensure efficiency.
Where is the Central Heating Pump Located?
In the system or regular boilers, the central heating pump is mostly located either in the airing cupboard or next to the boiler itself. On the other hand, things got a bit twisted for combi boilers.
Well, there is no external pump on a combi boiler for heating or domestic hot water. The combi boiler got an internal pump to pass the water via the radiators, while tap water uses main pressure to get supplied.
Most Common Central Heating Pump Problems & Solutions
No Water Is Being Pumped Despite the Pump Running
In most cases, the problem lies in the central heating pump in such a scenario. Although it’s running, you can feel through the slight vibrations it’s not pumping the water as intended. The cause of the issue is most likely the stuck propeller or the shaft inside the pump.
To fix the issue, all you have to do is gently tap the pump to free up any stuck component. You can use a light metal tool or a piece of wood to make the taping more effective and convenient. But if this issue is happening regularly, replacing the pump in no time is a good idea.
Dirt & Grime Is Blocking the Pump.
Another common issue with the pump is the building up of metal particles from the connected pipework and radiators or dirt that clogs it with time. When the pump is blocked, your heating system will either heat up a bit more than usual or not at all.
The one thing that can help us remove the dirt or clogged particles is hot flushing the heating system using appropriate chemicals. Additionally, when you have flushed the system, fit a quality magnetic system filter to catch and minimise debris or metal particles.
Noisy Central Heating Pump Due to Airlocks.
The airlocks are the most common issue with the pump and other heating appliances installed in the central heating systems. The pump will stop working or start working inappropriately if the air is built up. The humming noise started coming from the pump due to the airlocks.
The solution to this issue is quite simple. To start with, locate the small bleed screw given on the heating pump. Once you have found it, start opening the screw extremely slowly since water is collected in it. The air will first bleed out, followed by a small amount of water.
Note: If you still hear sounds from the pump, you can use anti-vibration brackets that many manufacturers supply and install them appropriately to overcome the sound issue.
Incorrect Pump Installation
Suppose the central heating pump has been working inappropriately since you installed it. In such a case, you can’t blame the pump; it may have been damaged or installed incorrectly from day one. Or, the original installed fitting is in the wrong manner, but this is the rarest case.
First of all, drain the system and remove the pump by turning it. Now, fit it correctly if it was fitted incorrectly before. But if this is not the case and the pump is not working fine, it is damaged. In this situation, you have to replace it with an all-new pump.
Incorrect Pump Speed Settings
Although it’s uncommon in old central pumps, the newer pumps have different levels to set speed and flow settings. There are typically three levels, 1, 2, and 3, where ‘1’ represents the lowest flow rate while ‘3’ is the highest. If the radiator or system isn’t getting hot, flow speed is the issue, and you should change it.
On the top of the pump, there is a switch given, and it is set to any of the points between 1 to 2. If it’s at 1 or 2, there is a huge chance that the flow rate is low, which is the issue. All you have to do is flick it to ‘3’, the highest flow speed level, to give the most powerful speed settings.
Note: It’s suggested to consult with your central heating system provider or a Gas Safe engineer before changing the flow speed. This is because there are chances that it’s intentionally set at that level, and the system allows only up to that level. Or, the microbore pipes don’t all flow further. If you increase the flow speed, it may damage components and cause leaks.
The Pump is Leaked or Dripping.
I have seen leaked boilers due to a wide spectrum of reasons. But most of them were having issues with the pump. When we further break down the issues with the pump that can cause it to leak, these include incorrect installation, blown seal because of incorrect pressure settings, or the pump working itself loose.
- Ensure that the pump is secured properly. For this, start by tightening up the pump to stop leaks.
- Now, check the pump fittings. Mostly, corrosion is the primary reason that causes the pump to leak water. There is only one solution: replace the central heating pump.
- Examine the pump joint. If the water is leaking and dripping from the joint of the pump, it stipulates that the seal is blown in most cases. For this, you can replace the seal or the entire pump if it’s particularly old.
The Pump and/or Boiler Have No power
Suppose there is power on your property, but both the pump and boiler have no power at all. In such a case, the PCB unit must be causing this issue. On the other hand, if the boiler has, but the pump doesn’t have power, it’s more likely to be an issue with the wiring.
- Start from the basics. First of all, you have to check the fuse on the pump and ensure it’s not blown. If it’s blown, replace it with a new one to resolve the issue.
- There is still a power issue. In such a case, it’s suggested to call a Gas Safe engineer to check the electrical wiring and troubleshoot and resolve the issue.
The Pump Is Not Turning Off
Although most of the pump-related issues cause the pump to either not work at all or work improperly. But there is a rare case when the pump starts operating continuously without switching off, even when necessary. If you ever face this issue, take help from this solution.
To resolve this issue, you need to make a thorough diagnosis. Well, the following could be the reasons for this issue.
- The pump’s overrun stat is defective.
- Faulty PCB(s).
- Stuck mid-position valve.
Note: If the issue is because of a stuck mid-position, you can use WD40 lubricant to lubricate the valve and turn it into a working state.
The Pump is Worn Out
Suppose there was an issue with the central heating pump from the one we discussed up to so far, and you tried the relevant solution to fix it. But it’s still there. Or, the pump isn’t working at all, and the only issue is the apparent wear and tear. Well, in such a case, age may be the one that is causing it to work improperly.
Note: The pump can last for almost 15 years in most cases. But if it’s a good quality one, it can even last beyond the 20 years of span.
There is only one solution: replace it. Well, if the central heating pump has lived its service life, it needs to be upgraded with an all-new one to ensure the proper working of your central heating system.