Farmborough's Local Boiler Installation Specialist

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.

Wood-burning stoves with a back boiler alongside a main boiler

Some older rural properties around Farmborough run a wood-burning stove with a back boiler feeding heat into the same central heating circuit as an oil or gas boiler, usually through a thermal store or a cylinder with two coils. Getting this combination to work safely means the stove's back boiler circuit has its own means of dissipating heat if the pump fails or a valve closes while the stove is still burning — a stove can't simply be switched off the way a boiler can if its heat has nowhere to go, so a gravity-fed safety circuit or heat leak radiator is normally required. It's a more involved design than a single-boiler system and needs planning at the point either appliance is replaced, not treated as an afterthought once the new boiler is already fitted.

Chasing pipework into lime plaster and stone walls

Solid stone or cob walls finished in lime plaster, common in the older parts of Farmborough, behave very differently to modern plasterboard when a pipe run needs chasing in. Lime plaster is softer and more porous than gypsum, so cutting a neat, consistent chase without blowing the surface needs a slower hand and finer disc than a stud-wall job, and any repair has to be made good in a lime-based skim rather than modern filler, which can trap moisture behind it and cause the patch to fail. On solid stone we sometimes surface-mount pipework in painted conduit instead of chasing, particularly where the wall is a significant structural thickness and chasing would weaken it. Knowing which approach a wall needs before starting avoids expensive plaster damage.

What a flue gas combustion analysis actually tells us

A combustion analyser measures the flue gases leaving a boiler — oxygen, carbon dioxide, and carbon monoxide content, along with flue temperature — and from those figures calculates the boiler's actual combustion efficiency and confirms it's burning cleanly rather than producing dangerous carbon monoxide. It's a required part of every gas and oil service and commissioning visit, not an optional extra, because visual inspection alone can't detect incomplete combustion. Readings outside the manufacturer's specified range point to a specific fault — a partially blocked burner, incorrect gas or oil pressure, or a fouled heat exchanger — rather than a general sense that something's wrong. We record the readings on every service so any drift between visits is visible, not just the pass/fail result on the day.

Single-pipe circuits in older stone cottages

A lot of the stone cottages and farmhouses around Farmborough were plumbed decades ago on a single-pipe gravity circuit, where each radiator draws from and returns to the same loop rather than having its own flow and return. It works, but radiators furthest from the boiler receive water that's already cooled after giving up heat to the ones before it, so the far end of the house is always the coldest. Converting to a two-pipe layout means new pipe runs, which in a stone cottage often means chasing lime plaster or lifting flagstones — not a trivial job. Where a full rewire of the pipework isn't wanted, we sometimes improve balance instead by oversizing the radiators nearest the end of the run and fitting TRVs to hold back the ones nearest the boiler.

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