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HomeKit reviewsSmart thermostatsHoneywell Home T6R-HW Wall-Mounted Wireless Heating & Hot Water Smart Thermostat (Y6H920RW5031)
Review · Smart thermostats

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

Our verdict
4.3 / 5

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.

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What we like
  • 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
Worth knowing
  • 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

Who shouldn't buy this

you want room-by-room zoning — evohome, Drayton Wiser and tado all support radiator valves and this does not.

Key specs

Works with24–230V on/off and OpenTherm boilers, heat pumps; S/Y/W-plan
ControlOpenTherm or relay; genuinely controls stored hot water
ZoningSingle zone only — no radiator valve ecosystem
FittingNo hub; 2-channel receiver needs a wired 230V supply
How this review works

Our rating is a considered spec-and-evidence verdict: we verify every specification against at least two independent sources, re-check the UK price on a schedule where we can track it automatically, and say plainly who a product isn't for. Commissions never change a rating. Read the full methodology →

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