• Welcome to PlumbersForums.net - The international free plumbing advice forum. Professional plumbers sharing advice with fellow plumbers and DIY alike. Register for free today! - Checkout the Plumbing Advice forum and then our Plumbing Videos area which still needs populating.

combi boiler

Tankless water heaters — also called instantaneous, continuous flow, inline, flash, on-demand, or instant-on water heaters — are water heaters that instantly heat water as it flows through the device, and do not retain any water internally except for what is in the heat exchanger coil. Copper heat exchangers are preferred in these units because of their high thermal conductivity and ease of fabrication.
Tankless heaters may be installed throughout a household at more than one point-of-use (POU), far from or without a central water heater, or larger centralized whole house models may still be used to provide all the hot water requirements for an entire house. The main advantages of tankless water heaters are a plentiful, practically limitless continuous flow of hot water (as compared to a limited flow of continuously heated hot water from conventional tank water heaters), and potential energy savings under some conditions due to the use of energy only when in use, and the elimination of standby energy losses since there is no hot water tank. The main disadvantage of these systems are their high initial costs (equipment and installation).

View More On Wikipedia.org
  1. J

    Combi boiler obsolete part dilemma

    Hi everyone, I have been searching the Web for a spare part for a Worcester 35 cdi ng boiler that is obsolete. I can't find one anywhere and its looking more and more likely I'm doomed . The part is the door extrusion seal 87161031280. I have sold my house STC and this has just happened , so...
  2. W

    Combi boiler - bang when hot water opened

    Hi All! I hope you can give me some advise. I had combi boiler (Viessman vitodens 100-w 30kW) installed about half year ago. Recently I start hearing one single bang when hot water is opened at any of taps around house. It sound like someone in other room will knock a radiator (not relly loud...
  3. M

    Shock arrester combi boiler

    I usually fit these on the cold feed to the boiler close to the boiler. But if fitting near the boiler would be unsightly. Would they still be effective fit somewhere else in the cold.feed in the system. Say under the kitchen sink? Thanks
  4. G

    combi boiler system draindown problem

    during drain down of system with all trc open and bleed valves open water just continues to drain out and boiler pressure remains at 1.5bar.Baxi combi boiler 105
  5. J

    Gloworm combi boiler help!!!

    Some advice would be very much appreciated. Our Gloworm Ultracom 38CXI combi boiler recently developed a few issues. Recently some our taps/shower but not all of them will run hot initially and then run cold after around 2 minutes of running hot. The heat exchanger was replaced by our...
  6. computermike

    Pipes in concrete floor with combi boiler

    I am looking to replace an oldish boiler and hot tank with a combi boiler. The house dates from around 1968 and quite possibly the (copper) piping could be that old. I had someone round to give a quote and they said they would not recommend a combi boiler because the piping downstairs was buried...
  7. A

    Can a council tenant have any say in where a new boiler is situated?

    The council are offering to update the fire and inefficient old radiators and replace the old fashioned boiler with a new combi one. They want to move the boiler from the tank cupboard in the bedroom to the much bigger walk-in wardrobe, presumably for convenience as there seems to be a gas pipe...
  8. J

    Combi boiler keeps locking out

    Hi everyone. I was hoping someone here might be able to help me with a problem I have. After using our shower for around five minutes it seems to be causing the boiler to lock out. It’s a thermostatic mixer shower running from a Worcester Greenstar 30si combi boiler. Weirdly, this only seems...
  9. S

    Need to renew 17yr old combi boiler.

    Renewing 17yr old Gloworm combi boiler, running dom h/w and 15 rads, 40% are doubles. Water flow from stop valve has been measured as 6L p/m, is that enough to run system effectively?
  10. C

    Old Combi Boiler Firestop Advice please

    Hi, We have 28 year old Valiant Combi Boiler in our Bungalow airing cupboard, where the vertical fan flue goes up into roof. As you can see in photo, we need a firestop plate, A) for fire safety B) Hopefully seal around pipe may stop warm air travelling through gap into roof space, and causing...
  11. Robert Tyrrell

    Combi boiler temperature differential

    2 years ago I installed a Baxi 836 and every year the owners complain about the water temperature. Last year I couldn't find anything wrong but this year there's definitely a low-temperature hot water output. Although this is usually a warranty claim I'm having difficulty with this as I messed...
  12. E

    new grants external oil fired combi

    Hi, is it ok to turn on and use new grants external oil combi boiler, before it gets commisioned next week ? or can this cause any damage at all, ? many thanks.
  13. C

    Combi boiler mystery issue

    Hello all, New here so please forgive my ignorance. I have a Main 24 HE combi boiler and it’s playing silly bugg*rs. When given power it runs constantly, providing both heating and DHW. We have to turn it off at the selector switch when we don’t want heating/hot water otherwise it just burns...
  14. D

    install combi boiler and pressurised hot water cylinder

    Hello, looking for a heating engineer to recommend / install a pressurised cylinder and combi boiler system. There is ufh for a living space and two bathrooms, and radiators for the rest of the house. It's a 3 bed 2 bathroom property with solar panels on the roof, located in ringwood bh24. Any...
  15. M

    Urgent advice - Replacing gravity water system

    We need an urgent advice, we have a gravity water system and we are in a middle of loft conversion. We are adding an en-suit in loft and prefer to have a good water pressure there. What we want, is to either be able to run multiple showers at once, or if one person is having a shower, other...
  16. P

    Combi sys losing pressure every 2 days 4 months but no sign of leak

    Combi boiler system losing pressure every 2 days. We've been topping it up for months now and have had various radiators replaced and flooring pulled up downstairs around each of the radiators but so far no leaks have been found. I'm at a bit of a loss of where the leak can be because given...
  17. R

    Baxi 228 combi boiler hot water flow rate poor?

    Hi, Just checking I'm not talking rot. Today I visited a house with a Baxi 228 combi boiler. The technical spec for the DHW output is shown in the image. Boiler was installed 27 months ago. Baxi is claiming 13.3 litres @ DT 30. I set the boiler DHW temperature to a high setting. I was...
  18. E

    Good afternoon , Can any one age this combi boiler ? TIA

  19. A

    Hot water only coming through while preheating

    Hia, I have a baxi instant combi boiler the hot water doesn't work at all. No faults showing. The only way I can get it to work is by putting the 'preheat' on....as soon as the preheat reaches the correct temperature the water goes cold and I have to wait for it to cool down so I can put the...
  20. R

    Advice on Combi Boiler

    Hello - I was hoping for some advice and opinions on a new combi boiler I currently have a 3 bed semi with a myson orion boiler (it isnt a combi) - the boiler was installed around 1989, hasn't given any problems and is still working fine. Due to the increase in gas prices it is time to change...
Creating content since 2001. Untold Media is a Registered Trademark.