An internal, external or integrated hot-tub heater changes where people sit, where fuel is loaded and which components remain accessible. These names describe layout. They do not, by themselves, establish heating speed, safe pipe dimensions or the installation clearances. Compare the approved drawings for the tub and heater together.
Internal or snorkel wood stove
The heater sits in the bathing vessel behind its guard, so the water surrounds much of the heated surface and external pipework is minimal. It can give a compact, direct system and leave more garden space. The heater and guard displace water and seating, create a hot component inside the tub and affect cover design. Confirm guard, clearances, fill level and cleaning access.
External wood stove
The heater sits beside the tub, preserving the internal seating area and keeping fuel loading outside. It needs its own stable base, hot zone, flue and an approved lower/upper water loop. Distance, port height, pipe diameter and slope are model-specific. It is best where the owner wants bathing space and can protect a visible, serviceable heater footprint.
Integrated wood heater
An integrated heater is built into a compatible shell arrangement and loaded from outside. It can produce a tidy footprint with less exposed connecting pipework, but it is not compatible with every vessel. Check how much internal volume it uses, how ash is removed, which panels remain accessible and what happens if the heater requires replacement.
Trace three separate access routes
First trace the bather’s route: steps, handholds, seating, guard and exit. Then trace fuel and ash handling, including a place to work without crossing a wet entry route. Finally trace service access to the heater, connections and drain. A compact photograph can hide a layout that leaves no room to remove a component.
For an external heater, include the stove and protected hot zone in the garden footprint. For an internal stove, assess the occupied space around its guard rather than counting the full tub diameter as seating. For an integrated heater, identify the panel and withdrawal route needed if it ever requires replacement.
Connections are part of the layout
A natural-circulation loop depends on the approved port heights, route and pipe dimensions. A pumped circuit has different requirements. Do not extend hoses, add isolating valves or move a stove to make a landscape drawing fit without the supplier’s approval. A change that looks cosmetic can restrict flow through a hot water jacket.
The external-stove connection guide explains what information to confirm with the installer. It does not supply a universal pipe specification.
Check the final plan at ground level
Mark the tub, heater, steps and maintenance area on the site. Show the installer any nearby fence, canopy, building opening or proposed deck. The appliance instructions and competent installation design determine clearances; a standard gap copied from a different stove is not evidence.
Confirm the cover opens and stores safely, the flue can be inspected, and required vents remain clear. Recessing the tub must not bury the heater connections or convert an accessible panel into a permanent wall. Keep a drawing and photographs before the surround is closed.
For fuel choice, use the wood-fired and electric routine comparison. For available combinations, use the UK hot-tub range. The layout decision is complete when bathing, operation and maintenance all fit the actual site.
