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hot water

Water heating is a thermodynamic process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heating. In industry, hot water and water heated to steam have many uses.
Domestically, water is traditionally heated in vessels known as water heaters, kettles, cauldrons, pots, or coppers. These metal vessels that heat a batch of water do not produce a continual supply of heated water at a preset temperature. Rarely, hot water occurs naturally, usually from natural hot springs. The temperature varies with the consumption rate, becoming cooler as flow increases.
Appliances that provide a continual supply of hot water are called water heaters, hot water heaters, hot water tanks, boilers, heat exchangers, geysers, or calorifiers. These names depend on region, and whether they heat potable or non-potable water, are in domestic or industrial use, and their energy source. In domestic installations, potable water heated for uses other than space heating is also called domestic hot water (DHW).
Fossil fuels (natural gas, liquefied petroleum gas, oil), or solid fuels are commonly used for heating water. These may be consumed directly or may produce electricity that, in turn, heats water. Electricity to heat water may also come from any other electrical source, such as nuclear power or renewable energy. Alternative energy such as solar energy, heat pumps, hot water heat recycling, and geothermal heating can also heat water, often in combination with backup systems powered by fossil fuels or electricity.
Densely populated urban areas of some countries provide district heating of hot water. This is especially the case in Scandinavia and Finland. District heating systems supply energy for water heating and space heating from waste heat from industries, power plants, incinerators, geothermal heating, and central solar heating. Actual heating of tap water is performed in heat exchangers at the consumers' premises. Generally the consumer has no in-building backup system, due to the expected high availability of district heating systems.

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  1. B

    hot water on combi boiler setting query

    Good morning, I have a query about the water dial on my boiler bought a few months ago (Vokera Easi-Heat Plus 25C Boiler) and apologies for no pictures. My hot water is fed via the combi boiler and cold water is mains fed. There are two dials under the flap one is for hot water and the other...
  2. S

    URGENT no hot water of heating

    I have no hot water or heating, my boiler has no error symbols, my cylinder has gone cold, pump seems to be working well it’s making the same usual noise/vibrations, pipe under th boiler are hot but none near the cylinder is! Can anyone help
  3. P

    Hot water but cold rads

    I have a Worcester Greenstar Ri Woke up this morning with plenty of hot water but a cold house. All the rads were luke warm. From searching online I tried switching the 3 port valve to manual. This seemed to result in the boiler heating and the rads became warm, however this only lasted for...
  4. S

    Clunk when switching on hot water heating system - non vented system

    Hi, about 5 years ago I had a new boiler fitted. The location of the boiler was moved so new pipes fitted. No problems. About 2 years ago I then needed to have my 3 way valve replaced, this is when issues began. Initially there was no heat and the system was drained several times, this...
  5. T

    Glow Worm Ultimate 30 C hot water but no heating.

    Hi everyone, hope you're all well and hopefully someone will be able to help with a problem I have. The boiler seems to fire up with heating no problem at the start of a program but will randomly stop heating. There are no error codes on the boiler and the thermostat (Climapro 2RF) shows no...
  6. A

    Clogged Faucets and Low Hot Water Pressure on 1 faucet

    I have 2 issues/questions. To start from the beginning, we just purchased and moved into a home at the beginning of November that has a private well, once we moved in I noticed we had water pressure issues. Upon investigation I found that all the faucets/fixtures with pressure issues were...
  7. C

    Whistling sound coming from Hot Water Cyclinder

    Hi there, I have a joule cyclone twin solar unvented pressurised hot water cylinder that is floor standing. Just recently, I have noticed when I turn on the hot water supply taps anywhere in the house, a whistling sound starts to come from the tank itself. It gets louder the more you open the...
  8. J

    Boiler cuts out before hot water temp satisfied.

    Hi all, My problem is that my oil-fired boiler cuts out before the hot water has reached the thermostat temperature set on the hot water cylinder. At best I get luke-warm water. I have a vented system and the heating side of the system looks like it is working fine. However, with the boiler...
  9. B

    Hot water temp Query

    Good morning everyone, I would like to know when you run the hot water tap in the bathtub by law/water regulation how hot should the water be set at without mixing any cold water? I used a thermometer today and it came at 45c, should it be higher or is that okay? I have a combi boiler in the...
  10. N

    New boiler; heating working but hot water in shower going off in 10 mins

    Hi, Just replaced my 20 years old Vaillant boiler with a Alpha E-tec 20S; all went smooth with chemical flush etc on the day. Didn't have any issues with heating but when taking shower first time water started to get luckwarm and cold at the end of 20 mins or so. Also another issue I have...
  11. B

    URGENT Leaking hot water tank

    My hot water copper tank has sprung a leak just below where the top fitted immersion heater screws into the tank. I have replaced the gasket but can now see a small squirt of water coming from the tank just below the raised threaded area. Is there a suitable product to repair the leak or do I...
  12. A

    URGENT Noisy boiler problem

    Can someone please advise as to what is causing this issue with my sons boiler
  13. A

    Hot water only when heating is on

    I have a grant vortex heat only boiler with a 2 port set up. At present I only get hot water if the heating is on. Ive checked both 2 port valves and they seem to work (they both don't spring back when energised), Ive checked the tank stat for continuity but now I've run out of ideas, can...
  14. C

    Hot water but no Central Heating with young children

    We have a Potterton Titanium Combi Gas Boiler which was setup with the wireless Nest Thermostat last year to provide heat to our radiators, heat up our unvented indirect cylinder to provide us hot water and to heat up our under floor heating in our kitchen. There is also one tap in the house...
  15. D

    Hot water dominating central heating?

    Hi all, Have just had a new Ideal Vogue Max 26 system boiler installed (s plan) - along with 9 new vertical rads downstairs, new 15mm supply pipes, new Stelflow tank - its connected to 4 old rads upstairs (2 TRV, 2 non TRV). Having a tricky time balancing the new system, but most rads are now...
  16. S

    RM cylinder coil 1 and soil 1 hot water storage

    I’ve got advantage invented hot water storage RM cylinder. I have got coil1 soil 1 Both are connected with copper pipe. Looks like one for heating and one for hot water but the soil 1 for hot water pipe has a stop cock What is the difference between coil1 and soil 1
  17. G

    Combi boiler making noises and pressure gauge jumping, when hot water is turned off?

    Hi, I am just after some advice on my Glow worm Combi Compact 80e. Background- The boiler started to drop pressure a few weeks ago and required occasional topping up. I searched everywhere I could for leaks on the rads,[pipes etc. Nothing found as yet. It got worse and I consulted a combi...
  18. F

    Hot Water Cylinder incorrectly connected

    I bought a new replacement indirect vented cylinder and immersion but it turns out that the plumber has wrongly connected it up and needs to rotate it. The water from the radiators is coming out of my hot tap. I have had to switch of the boiler, after it started making a noise and water came out...
  19. Matt0167

    Baxi inovia 30c no hot water

    Hi guys any of you lot familiar with these , Not firing for hot water at all doesn't even try, had the call brought a hot water flow sensor as it was only pennies saved going back to merchants , no joy . heating works fine. Can some one explain to me how the sensor works ( on a blue tab...
  20. A

    Vaillant Turbo Max 837E Hot water issues

    Hi looking for advice please Have Vaillant Turbo Max 837E boiler, the dial temperature set at 42 degree (on 10 clock where as used to be 2oclock if you know what I mean), however when water comes out the tap it continues to go warm, hot, boiling hot, cold, within 10 seconds it can go from 28...
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