In detail
Combi Conversions in Detail
A conversion is a genuinely involved job with several distinct stages, each of which affects how the finished system performs.
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01
Removing tanks, cylinder and reclaiming space
The cold water storage tank and feed-and-expansion tank (where fitted) are drained, disconnected and removed from the loft, along with their support timbers and associated pipework and ballcock fittings. On older Blackpool terraces this often frees up a surprising amount of loft floor space that's been unusable for decades.
In the airing cupboard, the hot water cylinder and its immersion heater are removed once drained down, along with the vent pipe and any associated valves. The cupboard is left as a clean, dry void; many customers use the reclaimed space for shelving or storage once we've finished.
02
Mains water flow and pressure testing
Before any conversion is quoted, we test the incoming mains flow rate and static pressure at the property. This determines which combi boiler is suitable and whether the incoming supply pipe needs upgrading from the stopcock to the boiler.
A property with poor mains flow, common on some older Fylde Coast streets with narrower supply pipework, may need a larger diameter supply pipe run, or in some cases isn't a good candidate for combi at all. We'll always tell you this at survey stage rather than fit a boiler that can't perform.
03
Gas supply upgrades
Combi boilers typically require a higher gas flow rate than the older back boiler or open-vented boiler they're replacing. We check the existing gas pipework diameter and route from the meter and upgrade it where the calculation shows it's undersized; this is a common oversight on cheaper conversions and one of the main causes of underperforming combis.
Where the existing meter or governor can't support the new boiler's demand, we'll flag this early so it can be arranged with the gas supplier before installation.
04
Pipework decommissioning and capping
All pipework serving the old tank and cylinder that's no longer needed is properly decommissioned: drained, cut back, and capped at a sound point rather than just isolated. Pipework left half-connected in a loft void is a common source of leaks and frozen pipes months down the line.
Where pipework is being reused to feed the new combi, it's checked for condition, flushed through, and fitted with new isolation valves where needed so future servicing is straightforward.
05
Back boiler removal and fireplace making good
Many older Blackpool and Fylde Coast properties still have a back boiler tucked behind a gas fire, particularly in 1930s semis and post-war terraces. Removing one involves disconnecting the fire, decommissioning the flue and boiler unit, and safely capping the gas and water connections.
Once the back boiler is out, the recess is made good: bricked up, boarded or fitted with a surround depending on what's wanted, so the finished fireplace looks intentional rather than like an abandoned appliance has just been pulled out.
06
When a system or regular boiler is the better choice
Combi isn't always the right answer, and we'll say so at survey if the numbers don't stack up. Households with high simultaneous hot water demand, several bathrooms running at once, a large family with back-to-back showers, often get better performance from a system boiler paired with an unvented cylinder, which stores hot water at mains pressure rather than heating it instantly on demand.
Properties with genuinely poor mains flow that can't be economically upgraded are also better served by a system or regular boiler with stored hot water. In these cases we'll quote both options honestly rather than push combi because it's the more common conversion.
07
Blackpool terraces, 1930s semis and old gravity systems
A large share of the housing stock across Blackpool, Poulton, Cleveleys and the surrounding areas is Victorian terrace or 1930s semi-detached, much of it still running the original gravity-fed layout with a loft tank and airing cupboard cylinder, sometimes alongside a back boiler that's decades old.
These properties often have narrower original pipework, older gas runs, and loft spaces that weren't designed with modern insulation in mind: all things that need checking before a conversion is quoted, not discovered halfway through the job. We've worked on enough of this housing stock across the Fylde Coast to know where the common surprises are and to price for them up front rather than adding extras later.
