How To

How to Replace a Central Heating Pump

How to Replace a Central Heating Pump

The central heating pump is the beating heart of your central heating system, efficiently circulating warm water around your system to heat your radiators and keep your home comfortably warm.

But what happens if you have a problem and the central heating pump fails? If you’re a competent DIYer, this is a job you can tackle yourself if you follow a few relatively simple steps. Otherwise, it’s time to call the plumber.

Why Did My Central Heating Pump Fail?

Central heating pumps fail for a variety of reasons. The most common are corrosion and a failure to flush through the system on a regular basis. If your pump isn’t circulating water round the system and the body of the pump feels hot, then you’ll need to fit a replacement.

If your existing pump has lasted for 30 years, then you may wish to replace it for a more energy-efficient model.

Choosing Your New Pump

If you’re replacing an older pump, check if it’s a standard size. If not, you may need special adapters.

Measure your old pump, and make a note of the maker’s name and any settings. It may be easier to take a photo.

Choose energy-efficient central heating pumps and don’t oversize – a professional will advise you on the best replacement pump.

What You’ll Need

You’ll need to equip yourself with the following tools and equipment:

– A new pump – choose the most energy-efficient model you can afford

– A plumber’s tool

– A screwdriver – use an electrical one

– A bowl or an old paint tray and some towels

– Paper and pen/your phone

First Steps

First, close down the central heating system by switching off the electricity. Never undertake a pump replacement while the current is running.

Now make a diagram of the wiring schematic so you’ll know how to connect the new pump. You could even wrap different colours of electrical tape around each wire for ease of reference and so you’re absolutely clear on what goes where. The simplest way may be to take a photo on your phone for reference.

Removing the Old Pump Unit

Now you’re ready to remove the faulty pump. First, close the service valves, which you’ll find on the body of the pump, either by hand or with your plumber’s tool. If no valves are present, you’ll need to drain your heating system completely.

To avoid any potential spillages, place an old paint tray or a bucket under the pump. Now locate the union nuts which hold the pump in place.

Gently turn the nuts anticlockwise (remember: left to loosen, right to tighten), and then remove the failed pump.

Replace the Pump

Ease the new pump into position, ensuring it fits snugly. Don’t be tempted to re-use washers, as they can can contract over time – fit new ones in the union nuts for a watertight seal. Tighten the nuts finger-tight before finishing the job with your adjustable spanner. Now you can check for leaks by turning on the service valves or refilling the system.

Next, you’ll need to make sure the unit is bone-dry before reconnecting the wiring according to the wiring diagram you made earlier.

Testing Your New Pump

Now to get your new pump up and running. Switch the electricity back on and kick-start the heating system by turning up the thermostat.

Now you’ve got the central heating system up and running, check for any leaks or significant discharge of water. You may want to call a plumber to make sure there are no problems with the new installation.

Complete Your Installation

Finally, it’s a good idea to bleed the system to make sure there’s no trapped air. Your pump will have a bleed screw that you turn anticlockwise until you hear a hiss. You’ll probably need to bleed the radiators as well to ensure the whole system is balanced.

Bleeding the system will help to safeguard against corrosion and protect your newly installed pump.

Maintaining Your Central Heating System

It’s a good idea to flush your system through occasionally and to add a descaler and a rust inhibitor to it. Some descalers need neutralizing before an inhibitor is added, and you should always add the same inhibitor as is already in the system. Check the manufacturer’s instructions.

Make sure your central heating system is serviced by a qualified professional on a yearly basis to keep it running efficiently.

Ask the Professionals

If you do run into problems with your central heating pump, Anchor Pumps have a comprehensive range of replacement pumps, including highly rated energy-efficient Grundfos pumps. Contact us for more details 0800 112 3134.

Troubleshooting Negative Head Shower Pumps

Shower pumps are generally reliable pieces of equipment, and problems rarely occur. When they do, it’s important to be able to diagnose them correctly in order to determine whether a new pump is needed or if the fault lies elsewhere.

Whether you’re using Stuart Turner shower pumps or another brand, the basics of troubleshooting are the same. Problems are generally due to either the pipework connections, the electrical supply or the pump itself. We’ll take a look at some of the most common issues and how to fix them.

Types of Pump

There are two main types of domestic shower pumps, and it’s important to understand the difference, as using the wrong type can lead to problems. A negative head pump is used where the shower head is level with or above the cold water storage tank – in other words, gravity alone can’t provide a sufficient flow for the shower. If the shower head is below the tank but water pressure is still low, then you need a positive head pump.

There are also universal pumps available that will work with either a positive or negative head type of system. If you have a combi boiler and no cold water header tank, then you need a pump that will boost mains pressure throughout the entire water system of the house, not just a shower pump.

Problems with Negative Head Pumps

Negative head shower pumps can sometimes suffer from the flow rate being too great at the shower head. You can solve this simply by fitting a larger head to cut the pressure and allow an even flow of water. Alternatively, you can try closing down the isolator valves for both hot and cold water on the output side of the pump slightly. Don’t close them by more than a third, and leave the valves on the input side fully open. You may have to use a bit of trial and error to find the right flow.

Electrical Problems

Often problems aren’t with the pump itself but with the electrical supply feeding it. If your pump isn’t operating at all, the first thing to do is check that the power supply is on. There will usually be a fused spur feeding the pump: if the power is on, locate the spur and check that the fuse hasn’t blown. If there’s a circuit breaker, similarly check that it hasn’t tripped. Should your pump continue to blow fuses after they’ve been replaced, then that indicates a fault with the pump itself – possibly a seized motor.

Some pumps have run-dry protection, which causes them to cut out to prevent damage if the water supply is interrupted. This can look similar to an electrical problem at first glance. If the run-dry cut-out has operated, you can reset it by turning the power off for ten seconds and then turning it on again. Open the shower tap to get any air out of the system.

Pump Noise

Noise from shower pumps is a common complaint. Check that the pump has been properly installed. Most are supplied with anti-vibration feet, so check that these have been properly fitted. Noise can be transmitted through pipework, so make sure all pipes to and from the pump are properly supported. Also check that any flexible hoses have minimal bends. If the pump makes a humming noise, this may indicate that it’s stuck. This could be due to an electrical problem or, in hard water areas, the pump being blocked by limescale.


Leaking from around the pump may be caused by a joint that hasn’t been sufficiently tightened or by badly fitted or worn washers. Pumps are usually fitted with isolation valves at either side, so it’s an easy matter to disconnect and re-seat the joints without turning off the whole water supply. If the leak is coming from the pump itself, then it may need to be serviced or replaced.

Save money by Winterizing your home in Summer!


It may seem a bit early to be thinking about getting the house ready for winter, but bit of work this weekend could save your a lot of money later, here’s why;

Insulation – Dull but Vital

If your roof insulation is on the thin side, you may get a better deal by upgrading it before the really cold weather comes in. It can make a colossal difference, turning a draughty terraced house into a cosy nest. Double-glazing windows pays dividends not just in reduced heating bills but in cutting down noise too.

Remember to lag pipes that are exposed to the cold, because in a severe winter you’ll get the misery and expense of burst pipes or even just the blockage that results when cold water freezes and you have no water coming out of the tap. For more advice on how to prevent frozen pipes click here.

Autumn Gales

All around England, Scotland and Wales, autumn sees the gales come in, especially around the coast. This is why you need to think about weather-proofing your house early on. The same double-glazing that keeps the heat in and the noise out will also stop your windows rattling in high winds, ensuring a better night’s sleep.

Take a look at the pointing on your chimney: it may need redoing to stop bricks being dislodged in high winds. This can be an expensive job if you need to put scaffolding up, so it’s better to do it at the same time as any other roof repairs you need. TIP: It might be worth checking with your neighbours as they might be willing to share the cost of scaffolding if they are planning any work, always worth a try.

Wind gets under any loose bits of wood, roofing felt or tiles and within minutes can rip a flat roof off, so make sure that everything is securely nailed or fixed down. Check fencing is secure, and take stock of the garden, checking that no loose items such as light garden chairs are likely to be picked up by the wind, causing damage to the house. Check shrubs or large bushes near the house, and trim back any branches that could fall or break off in high winds.

Clear the Gutters – They Can Be Full of Surprising Things

Rain can sometimes mean that a lot of weeds etc have taken root in the gutters and are spreading happily, ready to block the down pipes once the winter starts and they die down. They need to be taken out. Also, all kinds of objects can end up blocking guttering and downpipes – things like balls or other dropped by seagulls if you’re near the coast.

For the Elderly or Disabled

If you have vulnerable people living with you that might have trouble using steps, adding a grab rail is a must for the winter months! Slippery steps can be really dangerous for people with slower reactions or decrease strength. Rock salt is another essential to keep in the home ready for the freezing weather, it is best to pick this up now and have it in storage as it is difficult to predict when the icy storms will hit.

Fit Draught Excluders

It’s much easier to do jobs that involve having the front or back door open before the winter starts. So fitting draught excluders now can save you time in the long run. Stick-on versions are available and are really easy to fit if you have aren’t DIY-savvy. 

Empty the Pool

If you have a swimming pool, then it’s time to think about draining it, pumping out the excess water and cleaning it. It’s another job best done before the cold weather sets in. Think about upgrading to a more efficient swimming pool pump, which will help to get the job done more quickly with less power consumption and far less noise.

Boosting your low water pressure in the home

It isn’t uncommon for homes to suffer from low water pressure. If you’re experiencing symptoms such as a slow-filling bath, poor flow from the shower or inadequate performance from your combi boiler, then you too may be experiencing low water pressure.
But although it’s a widespread problem, that doesn’t mean it can’t be fixed. The solution lies in a booster pump / booster pumps in order to improve the flow and get things back to how they should be.
Type of Pump
One of the leading options for correcting low water pressure is the Home Boost range from Salamander pumps. These are able to raise your water pressure by around 1.5 bar whilst still ensuring you stay compliant with water-use and installation regulations. They’re compact and easy to install and quiet in operation too, so they won’t disrupt your home with extra noise. Intelligent control means that the pump will only operate when it’s needed, so it won’t hit your energy bills either.
Where to Fit
Your booster pump / booster pumps need to be installed on your incoming mains water pipe. It should be fitted after the stop tap but before the central heating boiler. The pump needs to be on rigid, fixed pipework. In this position it can boost the flow to all taps, showers and appliances like washing machines and dishwashers in your house.
The unit needs to be positioned with its inlet and outlets vertical, and it should be somewhere that’s protected from frost. Make sure that it’s easy to access for when it requires servicing too. Don’t box it in where you can’t get to it.
There’s a video showing the installation process and how quiet Home Boost pumps are in operation.


Installation is much simpler and quicker than for some other solutions. All of the fittings you need for installation are included in the pump kit. You get washers, a filter washer, a straight connector, an isolation valve connector and some adapters to cope with either 15mm or 22mm pipe connections. Full instructions are included too, so you’re ready to start installing as soon as you get the kit.
Installation should only take about an hour. If you’re not confident doing it yourself, you can get a qualified plumber to carry out the work for you. You’ll need to turn off the water supply at the stop tap and drain the pipes by running the taps before starting work.
You can then cut into the pipe to fit the pump – make sure you allow room for isolating valves as well as the pump itself. With the pump fitted, the inlet pipework needs to be flushed and the pump filled with water before you switch on the electrical supply to the pump. This makes sure you have no airlocks in the system.
Once the power is connected, the pump should activate automatically as soon as a tap is turned on. A light on the pump indicates that it’s operating. You can then enjoy your improved water pressure throughout the house. These great tips from Anchor Pumps will help you to install one properly.

How to Lower Your Central Heating Bill in 2016

Reducing the amount you spend on heating your home doesn’t mean you have to sacrifice your level of comfort. By making sure your insulation, thermostat and central heating system are all working in harmony, you can stay warm on the coldest of winter nights without spending a penny more than you need to.


A great first step is to check all around your home to make sure there are no gaps in insulation or draughts where heat can escape, as this will help keep the temperature more stable. Don’t fall for the common myth that it’s cheaper to keep your heating on all day than it is to only have it on when you are at home. No matter how well you insulate, there will always be some heat lost from your home, so keeping your boiler on when you’re out of the house means you’re simply losing more heat all day long.

If your radiators have not been fitted with thermostatic valves, you can only switch them on or off, which is a highly inefficient way of heating your home. Such valves are relatively inexpensive to buy, easy to install and allow you to cut your heating bills by giving you more control over the temperature in each room of your home.

Always ensure furniture is positioned in a way that does not block radiators, as this will prevent heat from circulating properly. Fitting radiator foil behind your radiators will help reduce the amount of energy absorbed by the wall by reflecting heat back into the room. Although you can purchase special foil tailor-made for this job, kitchen foil fixed with wallpaper paste so that the shiny side faces the radiator will work just as well.

Boiler technology has advanced by leaps and bounds in recent years. If your boiler is more than ten years old, it’s highly likely that you would be able to exchange it for a more efficient version and see a reduction in your heating costs. In reality, the cost of replacing a boiler means you would not see any financial benefit for many years, and a far more practical alternative is to have your boiler serviced on a regular basis to ensure it is providing optimum levels of heat using the least amount of fuel.

Another cheaper but highly effective way to make sure your heating system is working to maximum efficiency is to invest in a new programmable thermostat. This will ensure you house is maintained at the temperature you desire and that your boiler does not work more than is necessary.

If you are in the market for a new boiler, a combi model is the most economical option, as it heats water straight from the mains rather than storing it in a hot-water tank. Combi boilers are more compact than conventional boilers, so they can fit into a smaller space. One issue with combi boilers is that they can sometimes suffer a reduced flow if multiple taps are turned on at the same time. If you live in a large household with lots of occupants and multiple bathrooms that are regularly used at the same time, a conventional boiler that feeds a hot water tank is best.