Hot water: TOO HOT. Cold water: only from taps

[JohnD]

I can't make out what the wheelvalve is for. But it looks like you have an ordinary vented system.

BTW the thing you called a "tank" is actually a cylinder. You can call the things in the loft "tanks" if you like.

You can change the thermostat in the immersion heater yourself, it is in a watertight pocket so you don't have to drain the cylinder to change just the stat. Isolate the power and remove the old one so you can get a new one to match. If you don't want to do it yourself any local plumber or electrician will do it easily, but ask round friends and neighbours for a recommended local person. Before doing any work on the immersion heater, don't just turn it off at the switch, remove the fuse or turn off the MCB in your consumer unit, and, if there is anyone else in the house, attach a label saying "do not turn on." Test that there is no live electricity present with a multimeter (not just a neon screwdriver)

as your immersion heater failed hot, it is not the latest type (which will automatically shut off to prevent boiling you in your bath like a lobster) and as you have been running it 24 hours a day it will presumably be nearer the end of its life than if you just used it in summer. however fitting a new immersion heater needs a partial drain as water will gush out, so leave that until either it fails, or you are having other work done on the system. You might consider having a timer fitted to the immersion instead of an on/off switch as this will also save you money.

I am just a householder, not a plumber or heating engineer.

 

[Janderclander]

You can change the thermostat in the immersion heater yourself, it is in a watertight pocket so you don't have to drain the cylinder to change just the stat.

The thermostat is just that small white box attached to the cylinder, yes?. That is where I adjust the temperature and can be removed easily. It is just being held there by the white string around the cylinder. I found a new one on ebay for £7.00. Just need to open it and reconnect the cables on the new one, I suppose.

 

[JohnD]

NO!

that is the thermostat that controls heat from the boiler to the cylinder.

the immersion heater has a long rod-like thermostat with a bigger plastic head (and a small adjusting dial) that you acces by removing the plastic cap from the top of the immersion heater.

immersion heater

immersion heater thermostat (older ones have a reddish brown head)
they vary so take out the old one and get a new one to fit

 

[Janderclander]

Ok

Thanks very much. You saved me £7.00 from the wrong thermostat I was going to buy, plus £100s from the plumber I would have called after seeing it did not fix the problem, plus ££££s on electricity bills since, once fixed, I would probably had switched it on 24hours again. I will start using the gas boiler from now on for water as well as heating.

Only question is, before, I used to have hot water available anytime (at a cost I now realize), while now, if I use the timer for the gas boiler HW, I kind of have to limit the times I can wash the dishes, put the washing machine on, have a shower, etc. If, lets say, I set it on for 3 hours in the morning, 6am until 9am, at what time approximately will the water lose the temperature? How many hours a day do people usually set it on for? My timer admits 2 slots of ON / OFF a day so maybe 3hr in the morning and 3 in the evening? Thinking more of the weekends rather than weekdays, when I will put it on only when I am at home.

Cheers

 

[JohnD]

the cylinder will get hot in 20 minutes. If you leave the boiler on, it will stop heating once the cylinder stat tells it the water is fully hot.

If you actually turn the boiler off, the cylinder will stay hot for 24 hours (unless you use up all the hot water) though it will gradually cool down. one cylinderful will easily do all your washing up for the day. It usually has about enough to do one decent bath. however if you have two or more people wanting baths, you just leave the boiler running, and by the time the first person has finished, it will be hot again (an immersion heater is far slower, as the boiler is much more powerful).

I usually leave my hot water on all day if I am going to be at home; otherwise on in the morning and evening.

Many timers/programmers have a single button or switch to change it from twice a day/all day/24 hours a day on/all off, as well as the timer. You can use this at weekends or holidays without having to change the timer.

It would be a good idea to put some climaflex pipe insulation round all those copper pipes. it will only cost you a few pounds at the DIY shed. Look to see about how much you have of each size of pipe - it will be 15mm, 22m and 28mm. the thinner economy insulation will be easier to fit if the pipes are tight to a wall.

 

[TicklyT]

For information, the small white box strapped on the side of the cylinder is the thermostat that (indirectly) controls the gas boiler. When it switches, you may see a lever on the 3 port valve move to a different position. This valve controls the flow of heat to the radiators or hot water.

We find that running our boiler for about an hour morning and evening each day provides enough hot water for our daily needs.

PS. if your immersion heater has been running 24/7, and your electricity supplier has been sending you estimated bills, check your electric meter reading against their estimates to make sure you aren't in for a nasty surprise when they do turn up to read the meter....

 

[Janderclander]

Thank you all.

Someone mentioned the immersion heater is only used as a backup or during the summer. Why would I switch from gas to electric during summer? Isn't it better to use always the gas boiler whether I also use the radiators or not?

 

[markplumb]

it's there as a backup in case your boiler ever breaks down. like TickyT said set your hot water for an hour in the morning and an hour in the evening summer and winter. the stat on the cylinder will knock the boiler off when the cylinder is hot (might only take 20mins).