Electric boilers, pros and cons
Electric boilers avoid combustion entirely (no flue, no CO risk, no Gas Safe requirement) but electricity typically costs more per unit than gas, so running costs can be higher for the same heat output. They suit smaller properties or as a backup rather than being the default choice for most UK homes.
Solar thermal (hot water) systems
Solar thermal panels heat water directly (different from solar PV, which generates electricity) and work alongside a conventional boiler or immersion heater as backup for when there isn't enough sun. They need a compatible cylinder with an extra heating coil, so retrofitting to an existing system isn't always straightforward.
Oil-fired boilers, what's different
Oil boilers are common in properties off the mains gas network, need an oil storage tank with its own maintenance and safety considerations, and are serviced by OFTEC-registered engineers rather than Gas Safe (which only covers gas). If you're off-grid, confirm your engineer's OFTEC registration specifically.
Boiler installation certificates, explained
A new boiler installation legally requires a certificate under the Gas Safety (Installation and Use) Regulations 1998, issued by the Gas Safe registered engineer who did the work. You'll need this when you sell the property, and some insurers ask for it if you make a claim involving the heating system.
Understanding the labour vs materials split
The boiler itself is often the largest single cost, but labour, flue work, and any additional pipework or radiator changes add up. If a quote looks cheap, check it specifies the same boiler tier (entry-level vs mid-range) as a competing quote, not just a lower labour charge.
Common heating engineer jobs
Heating engineers install, service and repair boilers and central heating systems: annual boiler services, fault diagnosis, radiator installation and balancing, powerflushing, and full system replacements. Many also work on unvented hot water cylinders and, increasingly, heat pumps and other low-carbon heating.
Smart thermostats and heating controls
A smart thermostat can improve control and, for some households, cut heating costs by learning usage patterns and allowing remote control — but it needs to be compatible with your specific boiler and wiring (some older systems need an additional wiring centre). Worth confirming compatibility before buying one separately from your engineer.
Red flags in a cheap heating quote
A quote well below others is worth questioning — check it specifies a named boiler make and model (not just "combi boiler"), includes a powerflush if the system is older, and states the warranty length. No Gas Safe registration number offered unprompted is a clear red flag.