Know two things before anything else

Most of the plumbing jobs we do could have been smaller if someone had noticed a month earlier. Not because people are careless, but because nobody tells you what to look at. This is what we would check in our own houses, what we would leave alone, and the signs that mean the time for checking has passed.

Where the stopcock is. Usually under the kitchen sink, sometimes in a downstairs toilet, a garage, or a cupboard by the front door. Find it now, turn it off and on once so you know it moves. A stopcock that has not been turned in twenty years may not turn when a pipe bursts at midnight. If it is seized, that is a job worth doing before you need it.

What kind of hot water you have. A combi boiler heats water on demand and has no tank. A system with a cylinder, in an airing cupboard, stores hot water. It matters because the warning signs are different, and because a cylinder has its own pressure and safety valves that need looking at.

Every month or so

• Under the sinks. Kitchen and bathroom. Run the taps, look at the trap and the isolating valves, feel for damp. A drip here is cheap; the cupboard base it ruins is not.
• Around the toilet base. Any water, any movement of the pan, any smell. A leaking pan connector or a failed seal shows here first.
• Boiler pressure gauge, if you have a combi. It should sit at roughly 1 to 1.5 bar when cold, though you should check your own boiler’s manual for its exact range. If it keeps dropping, something is leaking, and it is often somewhere you cannot see.

Every season

• Autumn. Bleed radiators before the heating goes on properly. Cold at the top means air, and bleeding fixes it. Cold at the bottom means sludge, and bleeding does nothing. Check the outside tap is isolated and drained if it has an isolator, and lag any exposed pipe, especially the condensate pipe from the boiler, which is the one that freezes and shuts the boiler down on the coldest morning of the year.
• Winter. If you go away, leave the heating on low rather than off. A frozen pipe costs more than a week of low heating.
• Spring. Look at the gutters and the gullies where downpipes meet drains. A blocked gully backs water up against the house.
• Summer. Run the heating for ten minutes once a month so the pump and valves do not seize. Book the boiler service now, not in October when everybody else does.

Once a year

• Boiler service. Not a look at the casing, a set of measurements. A service is also when a slow leak inside the boiler gets found before it takes out the circuit board. Ours is £99 + VAT.
• Cylinder, if you have one. An unvented cylinder has an expansion vessel, a temperature and pressure relief valve and an expansion relief valve. Manufacturers specify an annual check of these and it is normally a condition of the cylinder’s warranty. It is not a legal requirement in the way a landlord’s gas safety check is, but it is the check that stops a safety device failing quietly. Installing or working on an unvented cylinder is different: that legally requires an engineer holding the G3 qualification. If your cylinder has a discharge pipe outside that drips, that is a fault, not a feature.
• Water softener, if fitted. Salt levels and a look at the bypass valve. A softener left to run out of salt is just a tank.
• Flexible tap connectors. The braided hoses under basins and behind toilets. They have a working life and they fail without warning. If yours are more than ten years old or look corroded, replace them. It is a cheap job and a burst one floods a house.

What to leave alone

There is a category of jobs where the do-it-yourself version costs more than the plumber.

• Anything on the gas side of the boiler. Legally a Gas Safe engineer, no exceptions. Ours is registered 956889.
• Unvented cylinder valves. They are safety devices, and working on an unvented system legally requires the G3 qualification. Adjusting them yourself is dangerous and will usually void the warranty.
• Chemical drain cleaner for a recurring blockage. It clears the symptom, damages older pipes, and the blockage comes back because the cause was never found. If it blocks twice, the second time needs a camera, not a bottle.
• Re-pressurising the boiler more than once a month. Topping up is fine occasionally. Doing it every week means there is a leak, and the fresh water you keep adding is corroding the system from the inside.
• Lifting a toilet to check the seal. Once it is up, it needs a new connector and seal to go back down properly. If you suspect the seal, have someone lift it who has the parts in the van.

The nine signs that something is already wrong

Maintenance is for before these. Once you see one of them, it is a repair.

1. Drains that are slow, or gurgle when something else empties. Air is being pulled through a partial blockage. It will not clear itself.
2. Low pressure at one tap but not others. A blocked aerator or a failing isolating valve on that run. Low pressure everywhere is a different problem: the stopcock, the incoming main, or on a combi, the boiler.
3. Banging or knocking when a tap closes. Water hammer. Pipes not clipped, or a valve closing too fast. It shakes joints loose over time.
4. A damp patch on a ceiling below a bathroom. Almost always the bath or shower seal, the shower tray, or a waste. Do not paint over it. It comes back, and by then the joist is wet.
5. A smell from a drain that comes and goes. A dried-out trap, a cracked pipe under the floor, or a vent problem. The intermittent ones are the ones worth chasing.
6. A water bill that has gone up with no change in use. Something is running that you cannot hear. A toilet that fills quietly, a leak under a floor, a dripping overflow. A leak test finds it.
7. A toilet that runs, or refills on its own. The flush valve or the fill valve. Cheap to fix and it wastes a surprising amount of water if left.
8. Discoloured water. Brown from the cold is the mains, and the water company should know. Brown from the hot only is the cylinder or the pipework. Either way, do not ignore it.
9. No hot water, or hot water that comes and goes. On a combi, often a diverter valve or a failing component that a service would have caught. On a cylinder, the immersion, the thermostat or the motorised valve.

Leaks you cannot see

The leaks that do the most damage are the ones under floors and behind walls. The signs are the boiler losing pressure, a bill that has risen, a floor that feels warm in one spot, or a damp smell with no visible source. Finding them used to mean lifting floors on a guess. It does not now: thermal imaging, acoustic detection and tracer gas find the leak first and open up second. That is what our leak detection service is for, and it is usually cheaper than the floor you would otherwise lift.

A note on hard water

Most of Hertfordshire, Bedfordshire and Cambridgeshire is on hard water, and that is the reason showers lose flow, kettles fur, and hot water cylinders lose efficiency. It is not a fault, it is the water. A softener is the fix if it bothers you; descaling shower heads and tap aerators every few months is the maintenance if it does not.

When to stop and call someone

Now, if:

• Water is coming through a ceiling. Turn the stopcock off first, then call.
• You can smell gas. Leave the property, call the National Gas Emergency Service on 0800 111 999, and do not switch anything on or off.
• The boiler is losing pressure daily.
• A blockage has come back after being cleared.
• There is any water near electrics.

Those are not maintenance. Those are the reasons we run a 24 hour emergency line, and there is no call-out fee in working hours.

Frequently asked questions

How often should I bleed my radiators?

At the start of the heating season, and whenever one is cold at the top. If you are bleeding them every week, air is getting in somewhere and that needs finding.

What pressure should my boiler be?

Roughly 1 to 1.5 bar when the system is cold, but check your boiler’s manual for the exact range because it varies by model. If it keeps dropping, there is a leak.

Is chemical drain cleaner safe to use?

Once, for a simple sink blockage, it is usually fine. For a recurring blockage or an older house with cast iron or clay drains, no. It damages the pipe and does not fix the cause.

How do I know if I have a hidden leak?

The boiler losing pressure, a higher bill, a warm spot on the floor, or a damp smell with no source. A leak test confirms it without lifting anything.

Do I really need a boiler service every year?

Yes. It is a set of safety and efficiency measurements, it is what keeps the manufacturer’s guarantee valid on a newer boiler, and it is when the small faults get found before they become the big ones.

Need a plumber in Herts, Beds or Cambs?

For anything on this list that has gone past maintenance, our general plumbing repairs team covers Hertfordshire, Bedfordshire and Cambridgeshire. Call 01462 506 374. Gas Safe registered 956889, no call-out fee in working hours, 12 month labour guarantee.