Honeywell Home T6R-HW Wall-Mounted Wireless Heating & Hot Water Smart Thermostat (Y6H920RW5031) review
An S-plan or Y-plan home with a hot water cylinder that needs one thermostat to run both.
By Tom Calder · Updated 24 July 2026 · Price checked against our tracker
The answer to a common and badly served UK problem: a single, sensible thermostat that controls both heating and a stored hot water cylinder. Resideo specifies it for 24–230V on/off and OpenTherm appliances including gas boilers, combis and heat pumps, and for Sundial S-plan, Y-plan and W-plan stored hot water systems with 24V and 230V zone valves, with no separate hub required. Screwfix lists a 5-year manufacturer's warranty for domestic use subject to proof of purchase and terms; the frost protection and holiday mode are built-in functions rather than any external certification.
£159.00 inc VAT at Screwfix, checked directly on 24 July 2026. Screwfix does not publish a live online stock figure for this line — only a local store check — so treat availability as normally stocked rather than confirmed in stock. Make sure the listing shows model Y6H920RW5031: the wired-only T6 variants are different products with different specifications.
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- Genuinely controls a stored hot water cylinder as well as heating
- Specified by Resideo for S-plan, Y-plan and W-plan systems, 24V and 230V zone valves
- No hub to buy, and Screwfix lists a 5-year manufacturer's warranty for domestic use
- Single zone only — there is no radiator valve ecosystem for room-by-room control on this product
- The 2-channel receiver box always requires a 230V supply wired in at the boiler or programmer position
- Ignore the 'suitable for all boilers' retailer wording — Resideo makes no universal claim, and unsupported systems such as solid fuel are out
Key specs
| Works with | 24–230V on/off and OpenTherm boilers, heat pumps; S/Y/W-plan |
| Control | OpenTherm or relay; genuinely controls stored hot water |
| Zoning | Single zone only — no radiator valve ecosystem |
| Fitting | No hub; 2-channel receiver needs a wired 230V supply |
Our rating is a considered spec-and-evidence verdict: we verify every specification against at least two independent sources, track the UK price daily, and say plainly who a product isn't for. Commissions never change a rating. Read the full methodology →
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