Baxi 800 vs 600 vs Assure: which suits which home

Baxi's current domestic range splits into three tiers. The 800 is the flagship, a compact combi in 25kW, 30kW and 36kW with system and heat-only options and Baxi's longest warranty. The 600 is the everyday mid range for straightforward swaps. The Assure is the installer and social-housing line. The data plate, not the badge, decides the job.

What is the Baxi 800 best for?

Small to medium homes, and tight cupboard installs in particular. The 800 is Baxi's flagship range, a compact and light combi sold in 25kW, 30kW and 36kW outputs, with system and heat-only versions for homes running a cylinder. The last two digits of the model number give the output, so an 830 is the 30kW combi. Its selling point for the customer is the warranty: Baxi advertises up to ten years parts and labour on the 800, but only when a Baxi magnetic system filter is fitted and maintained, the warranty is registered within thirty days, the Benchmark checklist is completed and the boiler is serviced every year. Miss any of those and it reverts, so set the customer's expectations against the current terms rather than the headline number.

Where does the Baxi 600 fit?

Everyday combi and system replacements in small to medium homes on a tighter budget. The 600 sits below the 800 on features and warranty, and its combis run 24kW, 30kW and 36kW with maximum flow rates rising up the range, so the 36kW moves more hot water than the 24kW for a busier household. Baxi advertises a seven year parts and labour warranty on the 600, again tied to registration, the Benchmark record and annual servicing. For a one-bathroom property with ordinary hot water demand, the 24kW or 30kW is usually enough. Where the customer wants the longer cover or the compact flagship casing, look at the 800 instead.

When do you reach for the Baxi Assure?

On installer-led and social-housing work, and where a broad spread of formats matters more than the longest warranty. The Assure range spans combi, system and heat-only, so it covers most domestic replacements from one line. Its standard warranty is Baxi's shortest, two years parts and labour, with extended cover available on request, which is worth flagging to a landlord or housing client weighing up lifetime cost. As with every Baxi, the warranty must be registered within thirty days and the install completed by a Gas Safe registered engineer, or the cover is invalidated.

What to check before you quote

• The data plate: read the exact model and output from the appliance, not from the customer's paperwork or an old invoice.
• Model number: the last two digits usually give the output in kW, so an 830 is a 30kW combi. Confirm it on the plate.
• Hot water demand: bathrooms and simultaneous use decide the output, and combi versus system.
• Warranty conditions: filter, thirty-day registration, Benchmark record and annual service all change the length of cover, and the terms differ between the 800, 600 and Assure.
• Siting: the 800 and 600 are built compact for cupboard swaps, but always confirm clearances and flue routing on site.

Whichever tier goes on the wall, the paperwork is the same job every time. Manifold builds the CP12 and service record from the check on your phone, reads the make, model and GC number off the data plate with PlateScan, and keeps the property's appliance history ready for the next visit.