Pressure Keeps Dropping? We Track Down the Leak Causing It in Dudley

A Sealed System Should Not Need Constant Topping Up

Central heating is a closed loop. The same water circulates round and round, and in a healthy system the only reasons to add more are that radiators have been bled or that work has been carried out. If you find yourself reaching for the filling loop every couple of weeks, or the gauge sits low each time the heating has been off for a while, the circuit is losing water. The rate of loss matters as much as the location: a slow weep can go on for a year without visible damage, while a faster leak will eventually stain ceilings or lift flooring.

A single visit cannot always prove where a leak under a floor is escaping, but we can usually narrow it to a component or a section of the system and explain the next step plainly.

The Causes We Work Through

The pressure relief valve. This safety device opens if pressure gets too high and should reseat afterwards. Once it has lifted, grit or scale on the seat can stop it closing fully, and water then trickles continuously out of the discharge pipe. A wet or stained outlet outside is a strong clue, and the loss is often steady rather than intermittent.

The expansion vessel. As water heats it expands, and the vessel gives that expansion somewhere to go. If the internal diaphragm has failed or the air charge has been lost, pressure rises sharply when the boiler runs, the relief valve discharges, and the gauge reads low once everything cools.

Visible joints and valves. Radiator valve glands and compression nuts are frequent culprits, especially where a valve has been turned recently. Look for green or white staining, crusting, or a damp patch beneath a valve rather than a running drip.

Hidden pipework. Pipe under floors, in wall chases or beneath a concrete screed can weep for a long time. Damp patches, lifting laminate, musty smells and unexplained stains on a ceiling below are all worth mentioning when you book.

The boiler itself. Internal seals, diverter valve bodies and heat exchanger connections can lose water into the casing. This usually shows as corrosion, a drip tray with water in it, or a boiler that needs topping up more often than the rest of the system warrants.

A passing filling loop. Less common but easily missed: a filling loop valve that does not close fully keeps the circuit connected to the mains, so pressure creeps up rather than down. We check for this because it changes the diagnosis entirely.

How We Investigate

We start with the evidence you already have: how often you top up, what the gauge reads hot and cold, and where you have seen damp. On site we inspect every visible radiator valve and joint, check the relief valve outlet, test the expansion vessel charge where it is accessible, and confirm the filling loop is properly closed. Temperature patterns across the radiators can point to a section with poor flow, and isolating parts of the system is sometimes the quickest way to prove which leg is leaking. Where a leak is likely under a floor, we explain what access involves before any boards are lifted.

Repair Options and Their Limits

Some causes are quick: a new valve tail, a reseated compression joint, a replacement relief valve or a recharged vessel. Others take longer, such as cutting out and replacing a corroded section of pipe or repairing a joint beneath a floor. Parts are quoted separately and we confirm they suit your system before ordering. We do not promise that every leak is accessible without making good, and decoration or flooring reinstatement is not part of the repair unless we agree it separately. Where a leak is on the gas side of a boiler, we refer to a Gas Safe registered engineer; Maintenance Men never carries out gas work.

Living With It Until We Attend

If the gauge is below the maker's minimum, do not run the heating. Top up only to the cold figure if you know how, and leave the boiler off if it has locked out. If water comes through a ceiling, turn the stopcock off if safe, catch the drip and keep anything electrical clear. A suspected gas leak is never our booking: call 0800 111 999 from outside.

Stopping It Happening Again

Once fixed, a correct cold fill, fresh inhibitor and a magnetic filter will slow corrosion and reduce the chance of another joint failing. Note the gauge monthly to catch a new loss early.

Arrange a Pressure Loss Investigation

Book with your boiler make and model, the pressure readings hot and cold, how often you top up, and any damp or staining you have noticed. We work across the West Midlands and can sometimes attend the same day, though that is never guaranteed. We take the booking fee up front, the hourly labour rate depends on how soon you need the visit, and we quote the full total for your approval before we begin.