[jives11]

hi,

I have a fully pumped gas CH + HW system, with a hot water tank. The
tank has a topup immersion in the top, and a thermostat strapped to
the outside, contacting the cylinder through a cut away in the foam
insulation.

I also have E7 electricity which with offset washing machine +
dishwasher works out fractionally cheaper if I can offset around 9% of
total use. I'm experimenting with using the immersion for an E7 boost.
My gas bill is very high and I think the efficiency of Gas heating of
my water is compromised by too complex a layout and too many heated
towel rails , also possibly poor insulation on the pipe runs

My question is regarding the immersion heater. I have noticed that if
I turn it on after a while it appears to get turned off, or rather it
is on but not drawing current. I can see this from one of those
currentcost electricity monitors that measure the total mains. So If I
get up at 6:00am and turn on the immersion, the house consumes around
3.5Kw, but after around 45 minutes it drops to around 400 watts.

I assume this is because the water is hot enough, and that is a good
thing, but I'm curious what is doing that ? Is it the strap on tank
stat ? If so the light in the immersion switch is still on ? Maybe
there is a stat in the heater element itself ?

I'm not complaining, if the immersion cuts out when it's done it's job
- that's great , I'd just like to understand how .

[Trevor Smith]

"jives11" wrote in message
...

hi,

I have a fully pumped gas CH + HW system, with a hot water tank. The
tank has a topup immersion in the top, and a thermostat strapped to
the outside, contacting the cylinder through a cut away in the foam
insulation.

I also have E7 electricity which with offset washing machine +
dishwasher works out fractionally cheaper if I can offset around 9% of
total use. I'm experimenting with using the immersion for an E7 boost.
My gas bill is very high and I think the efficiency of Gas heating of
my water is compromised by too complex a layout and too many heated
towel rails , also possibly poor insulation on the pipe runs

My question is regarding the immersion heater. I have noticed that if
I turn it on after a while it appears to get turned off, or rather it
is on but not drawing current. I can see this from one of those
currentcost electricity monitors that measure the total mains. So If I
get up at 6:00am and turn on the immersion, the house consumes around
3.5Kw, but after around 45 minutes it drops to around 400 watts.

I assume this is because the water is hot enough, and that is a good
thing, but I'm curious what is doing that ? Is it the strap on tank
stat ? If so the light in the immersion switch is still on ? Maybe
there is a stat in the heater element itself ?

I'm not complaining, if the immersion cuts out when it's done it's job
- that's great , I'd just like to understand how .

The emersion heater has its own thermostat, if you remove the top cover you
will see it and there will be a small adjuster with a temperature scale so
you can alter the temp at where it turns off.
The stat that's on the side of the cylinder is for the boiler and has
nothing to do with the emersion heater.
Trevor Smith

[Donwill]

"jives11" wrote in message
...

hi,

I have a fully pumped gas CH + HW system, with a hot water tank. The
tank has a topup immersion in the top, and a thermostat strapped to
the outside, contacting the cylinder through a cut away in the foam
insulation.

I also have E7 electricity which with offset washing machine +
dishwasher works out fractionally cheaper if I can offset around 9% of
total use. I'm experimenting with using the immersion for an E7 boost.
My gas bill is very high and I think the efficiency of Gas heating of
my water is compromised by too complex a layout and too many heated
towel rails , also possibly poor insulation on the pipe runs

My question is regarding the immersion heater. I have noticed that if
I turn it on after a while it appears to get turned off, or rather it
is on but not drawing current. I can see this from one of those
currentcost electricity monitors that measure the total mains. So If I
get up at 6:00am and turn on the immersion, the house consumes around
3.5Kw, but after around 45 minutes it drops to around 400 watts.

I assume this is because the water is hot enough, and that is a good
thing, but I'm curious what is doing that ? Is it the strap on tank
stat ? If so the light in the immersion switch is still on ? Maybe
there is a stat in the heater element itself ?

I'm not complaining, if the immersion cuts out when it's done it's job
- that's great , I'd just like to understand how .

Yes, you're quite right the immersion heater also incorporates a rod
thermostat which is obviously doing it's job.

Cheers
Don

[Calvin Sambrook]

"Trevor Smith" wrote in message
...

"jives11" wrote in message
...

hi,

I have a fully pumped gas CH + HW system, with a hot water tank. The
tank has a topup immersion in the top, and a thermostat strapped to
the outside, contacting the cylinder through a cut away in the foam
insulation.

I also have E7 electricity which with offset washing machine +
dishwasher works out fractionally cheaper if I can offset around 9% of
total use. I'm experimenting with using the immersion for an E7 boost.
My gas bill is very high and I think the efficiency of Gas heating of
my water is compromised by too complex a layout and too many heated
towel rails , also possibly poor insulation on the pipe runs

My question is regarding the immersion heater. I have noticed that if
I turn it on after a while it appears to get turned off, or rather it
is on but not drawing current. I can see this from one of those
currentcost electricity monitors that measure the total mains. So If I
get up at 6:00am and turn on the immersion, the house consumes around
3.5Kw, but after around 45 minutes it drops to around 400 watts.

I assume this is because the water is hot enough, and that is a good
thing, but I'm curious what is doing that ? Is it the strap on tank
stat ? If so the light in the immersion switch is still on ? Maybe
there is a stat in the heater element itself ?

I'm not complaining, if the immersion cuts out when it's done it's job
- that's great , I'd just like to understand how .

The emersion heater has its own thermostat, if you remove the top cover
you will see it and there will be a small adjuster with a temperature
scale so you can alter the temp at where it turns off.
The stat that's on the side of the cylinder is for the boiler and has
nothing to do with the emersion heater.
Trevor Smith

Trevor is absolutely right but the tone of your original question (that is
the fact you asked it at all) has me thinking that I should also add that
with the top cover removed there are almost certainly exposed live
terminals. *Only remove the cover with the circuit isolated at the consumer
unit*.

If you can still read uk.d-i-y, great. If not, my words arrived too late!