DIY Doctor

Main navigation

Worcester bosch greenstar 28i combi boiler radiators work but water not heating up?

Postby doffcocker » Tue Jun 01, 2021 10:00 pm

having a few issues with my boiler. worcester bosch greenstar 28i. has been serviced every year. last serviced in jan. i moved into this property in feb. been experiencing these issues since feb but in the past month has gotten much worse.

so radiators work fine they all heat up. the combi boiler came with its own control panel receiver plus thermostat.
its the waters for the sinks baths and showers. since feb, the water sometimes would go lukewarm instead of hot. the boiler pressure meter would be in the green zone, usually the middle but still the water from the taps and showers would stay lukewarm. the boiler would be turning on and the green light that indicates that the fire is on would also be on. but still lukewarm. the radiators would still work. the water would still be lukewarm even if the radiators were on or off. the only thing that would solve this issue and increase the temperature of the water is I would have to turn the valves under the boiler so that i could increase the pressure from green to borderline green/red.

but this would solve the issue for a few days to a week. eventually the pressure would normalize back to bang on the middle of the green area.

about a month ago, i bought several HIVE smart TRV's and a HIVE receiver and thermostat. the hive system has been installed for about a month and works well. but i have definitely noticed that in the past month this issue with the water has become more frequent and i have to turn the valves under the boiler right to the top of the red area. and even that doesnt give hot water it just gives lukewarm. the radiators still work perfectly.
Rank: Labourer
Progress to next rank:
Posts: 1
Joined: Tue Jun 01, 2021 9:52 pm


Simply Build It

  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!

  • Related Topics