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Ultimate₂ combi boiler

Exclusive combi boiler with 5 years warranty*

  • Leading combi boiler offering great performance
  • FREE 5 year warranty* with option to extend
  • £15 reward when registered through Club Energy
  • Available in 30kW and 35kW models

Our leading combi boiler

The Ultimate₂ is Glow-worm’s high performance, ErP A rated boiler range developed for the one off installer market, and exclusively manufactured for City Plumbing Supplies.

The Ultimate₂ combi is available in a choice of 30kW and 35kW models and offers both high DHW flow rates and flexible flue options. The high performance model also features a modulating Grundfos pump for reduced energy use, a manual pressure gauge for easy installation and a modern, bright, LCD display with a simple-to-use interface.

Designed using an automotive grade, aluminium heat exchanger, the Ultimate₂ offers proven reliability and performance whilst being light to install and also easy to maintain.

The complete Ultimate₂ range (available in combi, system and regular (open vent) options) is compatible with the full range of Glow-worm controls including the popular MiGo app based control.

The Ultimate₂ also comes with a £15 reward and a free 5 year warranty when registered through Club Energy; where installers can also benefit from business tools including the Plumbing Toolbox app, Gas Safe Notifications, Benchmark and some great rewards

*When registered through Club Energy

Features & benefits

  • Combi boiler range with choice of 30 and 35 kW outputs
  • Modern, bright, LCD display with easy-to-use interface
  • High quality, automotive grade, aluminium heat exchanger providing excellent performance
  • ErP A rated for efficiency - helping to reduce energy bills
  • Modulating Grundfos pump for reduced energy use
  • Manual pressure gauge to make installation easy
  • Uses familiar Glow-worm diagnostics for easy install & servicing
  • Inbuilt filling loop
  • Compatible with full range of Glow-worm controls, flues and accessories
  • Ideal for use with innovative MiGo app based control
  • 5 years parts and labour guarantee*
  • Telescopic flue option available
  • ø60/100 and ø80/125 flue options available
  • Wide range of accessories available including spacing frame and pipe cover plate
  • Plume Management kit compatible

*with option to extend



Ultimate₂ combi boilerUnits30c35c
Casing dimensions (H x W x D)mm740 x 418 x 300740 x 418 x 300
Weight (lift)kg3333
CH output minimum/maximumkW6.1/25.57.1/25.5
DHW output CH output minimum/maximumkW6.1/30.67.1/35.7
DHW flow rate storage/combi (35°C rise)l/min12.514.4
SEDBUK rating 2009 89.389.2
NOx class (natural gas) 55
LPG compatible  NoNo
ErP rating heating AA
Erp rating DHW AA
Heat exchanger materialAluminium/Stainless steelAluminiumAluminium
Burner type Pre-mixedPre-mixed
Fully modulating YesYes
DHW plate heat exchanger YesYes
Integrated hydrobloc YesYes
Suitable for sealed systems YesYes
Inbuilt filling loop IntegratedIntegrated
Inbuilt adjustable system bypass Yesyes
Inbuilt condensate trap/siphon YesYes
Inbuilt boiler frost protection 2 Stage2 Stage
Zero compartment ventilation YesYes
Pump ErP fully modulating GrundfosErP fully modulating Grundfos
Top (from top of boiler)mm300300
User interface
User display Super bright LCDSuper bright LCD
Diagnostics AdvancedAdvanced
User adjustable CH temperature control YesYes
User adjustable DHW temperature control YesYes
Water connectionsmm2 x 22/2 x 152 x 22/2 x 15
Maximum horizontal Ø60/100m99
Maximum vertical Ø60/100m99
Maximum horizontal Ø80/125m2525
Maximum vertical Ø80/125m2525
Optional plume management kit Ø60/100 YesYes
Optional spacing frame YesYes

*See manual for clearance if side panels are to be removed to assist future service and maintenance

** 5mm if removable panel/door

Related Products

Related Products

Climapro₂ RF Control

Climapro₂ RF

  • Two channel wireless programmable room thermostat
  • Backlit display provides advanced user control and functionality
  • Capable of room and weather compensation*
  • Simple to use handheld unit

Introducing MiGo

The personal heating assistant

  • Wi-Fi thermostat and easy-to-use app
  • Manage heating and hot water from anywhere
  • Reduces energy consumption, saves money
  • Internet weather compensation
  • eBUS communication

Climastat room thermostat

  • Easy to use
  • Extra low voltage
  • Simple & discreet 2 wire connection
  • Polarity not important

Climapro₁ control

Available wireless and wired

  • Annual service reminder function
  • Automatic update for summer and winter
  • Simple and discreet
  • Weather compensation ability (when used with optional outdoor sensor)



Alternative products

Alternative products

Ultimate₂ system boiler

Exclusive system boiler with 5 years warranty*

  • ErP A rated for efficiency - helping to reduce energy bills
  • FREE 5 year warranty with option to extend*
  • £15 reward when registered through Club Energy
  • Available as 25kW model

Ultimate₂ regular (open vent) boiler

Exclusive regular (open vent) boiler with 5 years warranty*

  • ErP A rated for efficiency - to reduce energy bills
  • £15 reward when registered through Club Energy
  • Lightweight boiler with cupboard fit dimensions
  • FREE 5 year warranty with option to extend*