The combi boiler's great trick was deleting the cylinder, and a generation of households spent the freed cupboard on towels. Heat pumps politely reverse the trade: stored hot water returns, and with it the question every compatibility check must answer, where will the cylinder live?
Home Comfort Assured Renewables measures exactly that across St Albans homes, and this is the cylinder-and-space half of the compatibility check.
Why the cylinder comes back
Heat pumps heat water steadily rather than instantaneously, so domestic hot water lives in a cylinder charged by the system: modern, unvented, well-insulated, and sized to the household's mornings. The photograph's cupboard install shows the ancestor arrangement, the existing system whose spaces the check surveys.
Houses that kept their cylinder convert easily: the space, pipework and habits already exist. Houses that went combi need the space found, which is a solvable, measurable problem, and precisely why it is checked before anyone quotes.
- Stored hot water returns with the heat pump.
- Kept-cylinder houses convert simplest.
- Combi houses need the space found and measured.
What the check measures
Space candidates get surveyed properly: the airing cupboard's true internal dimensions against modern cylinder sizes, loft options weighed for structure and access, utility corners and garages assessed with their pipe routes, and the household's hot water demand sized honestly from bathrooms and routines.
Routes matter as much as footprints: how the cylinder's pipework reaches the plant position, where discharge runs can go, and what the disruption of each candidate location honestly looks like. The check ends with ranked options, not a shrug.
- Real dimensions against real cylinder sizes.
- Demand sized from bathrooms and mornings.
- Pipe and discharge routes walked per option.
Combi households: the honest options
Losing the combi's compactness stings, so the options deserve honesty: reclaiming the old cylinder cupboard where it survives, sacrificing lesser storage where it does not, loft placements where structure and access allow, and compact or slimline cylinders where demand suits smaller stores.
What the check refuses is wishful thinking: undersized stores that run cold on the second shower, or placements whose pipe runs would haunt the install. Space found honestly once beats space regretted daily.
Plan the space before you need it
The cheapest cylinder space is the one preserved in advance: households mid-renovation can keep a cupboard's plumbing capped rather than deleted, run ducting while walls are open, and size a utility room with the future store in mind. Five minutes of foresight saves a conversion headache.
Home Comfort Assured Renewables folds that foresight into its advice across St Albans: the compatibility check tells you what the house offers today, and the planning conversation protects those offers through every refit between now and conversion.
Related pages
- Heating system compatibility checks
- Heat pump surveys and quote planning
- Get the space question answered
Questions customers ask
Do heat pumps always need a hot water cylinder?
Domestic hot water is stored, so yes in practice: a modern unvented cylinder sized to the household. The compatibility check's job is finding and ranking the spaces it could occupy.
We have a combi and no cupboard: can we still convert?
Almost always: reclaimed cupboards, lofts, utility corners and slimline cylinders between them solve most houses. The check measures the candidates and tells you the honest trade-offs.
What size cylinder does a family need?
Sized from bathrooms and routines rather than guesswork: enough store for the real morning rush with sensible reheat. Demand sizing is part of the check, not a later surprise.
The cylinder question is measurable: candidates surveyed, demand sized, routes walked, options ranked. Answer it early and the whole conversion loses its biggest unknown.
Home Comfort Assured Renewables answers it across St Albans as part of every compatibility check. The contact page books yours.
