Long Ashton's Local Boiler Installation Specialist

Oil tank bunding and fire valve rules

Off-grid properties around Long Ashton rely on oil, and OFTEC's technical standards (OFS T100) set out when a tank needs a bund — a sealed secondary container holding at least 110% of the tank's capacity — based on how close it sits to a watercourse, drain, or boundary, and whether it's within a certain distance of a building. A fire valve fitted at the tank outlet, with its sensor mounted above the boiler's burner, will shut off oil flow automatically if a fire starts, and it's now expected on virtually every new or replaced installation. We check both bunding and fire-valve provision on every oil quote, because retrofitting a bund after a tank is delivered and sited is a second job, not a five-minute add-on.

• Bund holds 110% of tank capacity minimum
• Fire valve sensor mounted directly above the burner
• Distances to boundaries and drains checked against OFS T100
• Applies to replacement tanks, not just new installs

What a proper heating quote should include

A quote worth relying on states the specific boiler or equipment model, the labour and materials it covers, whether a system flush and magnetic filter are included, what happens to old equipment removal and disposal, and what's excluded — an unexpected gas pipe upsizing or asbestos-containing material discovered during removal, for example, which can't always be known before work starts. It should also state who's completing the Gas Safe or OFTEC notification and Benchmark commissioning record, since that's the paperwork that protects both the manufacturer's guarantee and the property's compliance history when it's sold. A vague one-line quote makes comparing genuinely different offers difficult, because two prices that look similar can cover very different scopes of actual work.

• Specific make and model, not just "combi boiler"
• Flush and magnetic filter stated as included or excluded
• Old equipment removal and disposal covered
• Notification and Benchmark record responsibility stated

Boiler interlock: a Part L requirement, not an extra

Building Regulations Part L requires a "boiler interlock" on new and replacement heating systems — wiring arranged so the boiler and pump cannot run unless a room thermostat or a zone valve is actually calling for heat. Without it, a boiler can cycle needlessly even when no zone in the house wants heat, wasting fuel and adding wear. It's a wiring and control logic requirement rather than a specific product, so it can be satisfied by several different control layouts as long as the end result prevents that unwanted firing. We confirm interlock is correctly wired as part of every boiler installation and note it on the commissioning paperwork, because it's one of the checks Building Control or a competent-person scheme inspection will look for specifically.

Condensate soakaways where there's no convenient drain

Properties without a nearby internal waste connection or external gully for the boiler's condensate — common on rural plots around Long Ashton where the nearest drain run is a long way from the boiler's location — sometimes need a dedicated condensate soakaway instead. This is a small pit filled with granular material that the condensate, which is mildly acidic, can disperse into gradually rather than running to a drain at all. Sizing and siting it correctly matters: it needs to be far enough from foundations and sited where the local ground can actually absorb the modest but steady volume a boiler produces, particularly over a long heating season. Where ground conditions make a soakaway unreliable, running a longer insulated pipe to a proper drainage connection is usually the safer long-term choice even though it's more work to install.

Pumped-oil versus gravity feed: does it matter?

Older oil systems sometimes still rely on gravity feed, where the tank sits higher than the burner and oil flows down to it under its own weight; a pumped system uses the burner's internal pump to draw oil up from a tank at any level, including below the boiler. Gravity feed limits where a tank can be sited and is more prone to airlocks if the line runs dry, while a pumped system is more flexible on tank position but needs the pipe run and lift height kept within the burner pump's rated capacity — usually no more than a few metres of lift and a set maximum run length. When we replace an oil boiler we check which type the existing tank and pipework support before assuming a straight swap, because a tank sited for gravity feed may need repositioning or a different pump to suit a modern burner.

Combi, system or regular: which suits the property?

A combi boiler heats water directly from the mains on demand with no cylinder or tank, which suits smaller households with modest simultaneous hot water demand and properties with no loft or airing cupboard space to spare. A system boiler heats a stored cylinder, giving stronger and more consistent flow to multiple outlets at once — better suited to larger households or properties with more than one bathroom — while a regular (open-vent) boiler additionally needs a cold feed and expansion tank, usually only chosen now where an existing system layout makes it the simpler swap. On stock like victorian terraces and modern estates the right answer depends on bathroom count and existing pipework layout as much as household size, which is why we ask about actual usage patterns rather than defaulting to whatever's currently fitted.