We have a traditional hot water system that uses a storage tank for the hot
water, the heating of the water is primarily through a gas boiler with an
electrical immersion heater as back up.

I would like to connect the electric immersion heater up, so it works when
the Gas boiler switches to heat the water. Thus reheating the water at a
much faster rate.

I have tried to adjust the thermostats so they work in tandem, but have been
unsuccessful, either the water is heated to too high a temperature or the
electrical immersion does not kick in.

I was thinking of some sort of relay device that would switch the electrical
immersion heater on when the motorised valve is switched to open, but what
sort of relay would I buy and where from.? And if this was implemented would
it still just heat the water to the same temperature as set for the gas
boiler or would the water still be overheated?

On 12 May, 15:41, "Stuart" wrote:

We have a traditional hot water system that uses a storage tank for the hot
water, the heating of the water is primarily through a gas boiler with an
electrical immersion heater as back up.

I would like to connect the electric immersion heater up, so it works when
the Gas boiler switches to heat the water. Thus reheating the water at a
much faster rate.

I have tried to adjust the thermostats so they work in tandem, but have been
unsuccessful, either the water is heated to too high a temperature or the
electrical immersion does not kick in.

I was thinking of some sort of relay device that would switch the electrical
immersion heater on when the motorised valve is switched to open, but what
sort of relay would I buy and where from.?

16A contacts, 240v coil. Try rapid electronics, or any other
electronic/electrical supplier.

And if this was implemented would
it still just heat the water to the same temperature as set for the gas
boiler

yes, as long as your gas system has a tank thermostat. There are some
old systems without one, with those you'd get overheating, which can
be a safety issue.


NT

On 12 May, 15:41, "Stuart" wrote:
We have a traditional hot water system that uses a storage tank for the hot
water, the heating of the water is primarily through a gas boiler with an
electrical immersion heater as back up.

I would like to connect the electric immersion heater up, so it works when
the Gas boiler switches to heat the water. Thus reheating the water at a
much faster rate.

Why? Unless your hot water cylinder is too small you are simply
helping it with a more expensive fuel source.
You would be far better fitting a bigger, insulated cylinder


I have tried to adjust the thermostats so they work in tandem, but have been
unsuccessful, either the water is heated to too high a temperature or the
electrical immersion does not kick in.

I was thinking of some sort of relay device that would switch the electrical
immersion heater on when the motorised valve is switched to open, but what
sort of relay would I buy and where from.? And if this was implemented would
it still just heat the water to the same temperature as set for the gas
boiler or would the water still be overheated?

"cynic" wrote in message
oups.com...
On 12 May, 15:41, "Stuart" wrote:
We have a traditional hot water system that uses a storage tank for the
hot
water, the heating of the water is primarily through a gas boiler with
an
electrical immersion heater as back up.

I would like to connect the electric immersion heater up, so it works
when
the Gas boiler switches to heat the water. Thus reheating the water at a
much faster rate.

Why? Unless your hot water cylinder is too small you are simply
helping it with a more expensive fuel source.
You would be far better fitting a bigger, insulated cylinder


Some stab in the dark calculations

purchase new tank and have fitted £500 ??
differance between gas and electric 2p /kwh ??

2 hours per day * 365 = £14.60 per year

payback time 34 years

the present situation of every body wanting baths one after the other will
dissapear in a couple oy years time.

On 12 May, 16:48, "Stuart" wrote:
"cynic" wrote in message

oups.com...





On 12 May, 15:41, "Stuart" wrote:
We have a traditional hot water system that uses a storage tank for the
hot
water, the heating of the water is primarily through a gas boiler with
an
electrical immersion heater as back up.

I would like to connect the electric immersion heater up, so it works
when
the Gas boiler switches to heat the water. Thus reheating the water at a
much faster rate.

Why? Unless your hot water cylinder is too small you are simply
helping it with a more expensive fuel source.
You would be far better fitting a bigger, insulated cylinder

Some stab in the dark calculations

purchase new tank and have fitted £500 ??
differance between gas and electric 2p /kwh ??

2 hours per day * 365 = £14.60 per year

payback time 34 years

the present situation of every body wanting baths one after the other will
dissapear in a couple oy years time

Fit a TMV blending valve on the DHW outlet pipe from the cylinder.
About £30. Then have the cylinder water stored at 75 to 80C. The TMV
drops the DHW temperature to 50-55C or less. This stores more energy
and effectively increases the size of your cylinder, and still heated
with cheap gas.

wrote:

Fit a TMV blending valve on the DHW outlet pipe from the cylinder.
About £30. Then have the cylinder water stored at 75 to 80C. The TMV
drops the DHW temperature to 50-55C or less. This stores more energy
and effectively increases the size of your cylinder, and still heated
with cheap gas.

**** me, Drivel is back.

In article ,
Stuart wrote:
I was thinking of some sort of relay device that would switch the
electrical immersion heater on when the motorised valve is switched to
open, but what sort of relay would I buy and where from.

Rapid do a suitable one - 60-4383 - which is a 30 amp DPST with 240v AC
coil for 6.45 plus vat. It's PCB mounting and could be mounted on a bit of
veroboard with the appropriate tracks beefed up with some 2.5mm copper
stripped from TW&E and soldered to it. Fit 15 amp chock blocks to the ends
of the 2.5mm for external connections. And then mount it all in a suitable
box - I'd use an 'adaptable' metal one with knockouts, and earth the
casing. Use insulated spacers to fit the veroboard to the box, and remove
the tracks near to the mounting points. I think you'll find it difficult
to find a ready made 'box' to do this job at a reasonable price. The above
should cost no more than about a tenner.

http://www.rapidonline.com/

? And if this
was implemented would it still just heat the water to the same
temperature as set for the gas boiler or would the water still be
overheated?

The water will heat to the highest set thermostat - I'd set the immersion
one slightly below that of the boiler.

--
*Atheism is a non-prophet organization.

Dave Plowman London SW
To e-mail, change noise into sound.

On 12 May, 17:20, "Dave Plowman (News)" wrote:
In article ,
Stuart wrote:

I was thinking of some sort of relay device that would switch the
electrical immersion heater on when the motorised valve is switched to
open, but what sort of relay would I buy and where from.

Rapid do a suitable one - 60-4383 - which is a 30 amp DPST with 240v AC
coil for 6.45 plus vat. It's PCB mounting and could be mounted on a bit of
veroboard with the appropriate tracks beefed up with some 2.5mm copper
stripped from TW&E and soldered to it. Fit 15 amp chock blocks to the ends
of the 2.5mm for external connections. And then mount it all in a suitable
box - I'd use an 'adaptable' metal one with knockouts, and earth the
casing. Use insulated spacers to fit the veroboard to the box, and remove
the tracks near to the mounting points. I think you'll find it difficult
to find a ready made 'box' to do this job at a reasonable price. The above
should cost no more than about a tenner.

http://www.rapidonline.com/

? And if this
was implemented would it still just heat the water to the same
temperature as set for the gas boiler or would the water still be
overheated?

The water will heat to the highest set thermostat - I'd set the immersion
one slightly below that of the boiler.

Totally unnecessary. Read my previousl post.

In article .com,
wrote:
Rapid do a suitable one - 60-4383 - which is a 30 amp DPST with 240v
AC coil for 6.45 plus vat. It's PCB mounting and could be mounted on a
bit of veroboard with the appropriate tracks beefed up with some 2.5mm
copper stripped from TW&E and soldered to it. Fit 15 amp chock blocks
to the ends of the 2.5mm for external connections. And then mount it
all in a suitable box - I'd use an 'adaptable' metal one with
knockouts, and earth the casing. Use insulated spacers to fit the
veroboard to the box, and remove the tracks near to the mounting
points. I think you'll find it difficult to find a ready made 'box' to
do this job at a reasonable price. The above should cost no more than
about a tenner.

http://www.rapidonline.com/

? And if this was implemented would it still just heat the water to
the same temperature as set for the gas boiler or would the water
still be overheated?

The water will heat to the highest set thermostat - I'd set the
immersion one slightly below that of the boiler.

Totally unnecessary. Read my previousl post.

You've already told the OP what your 'solution' is. I have simply answered
his question.

--


Dave Plowman London SW
To e-mail, change noise into sound.

On 13 May, 01:23, "Dave Plowman (News)" wrote:
In article .com,
wrote:





Rapid do a suitable one - 60-4383 - which is a 30 amp DPST with 240v
AC coil for 6.45 plus vat. It's PCB mounting and could be mounted on a
bit of veroboard with the appropriate tracks beefed up with some 2.5mm
copper stripped from TW&E and soldered to it. Fit 15 amp chock blocks
to the ends of the 2.5mm for external connections. And then mount it
all in a suitable box - I'd use an 'adaptable' metal one with
knockouts, and earth the casing. Use insulated spacers to fit the
veroboard to the box, and remove the tracks near to the mounting
points. I think you'll find it difficult to find a ready made 'box' to
do this job at a reasonable price. The above should cost no more than
about a tenner.

http://www.rapidonline.com/

? And if this was implemented would it still just heat the water to
the same temperature as set for the gas boiler or would the water
still be overheated?

The water will heat to the highest set thermostat - I'd set the
immersion one slightly below that of the boiler.
Totally unnecessary. Read my previousl post.

You've already told the OP what your 'solution' is. I have simply answered
his question.

Because you couldn't think of anything else, as you don't know about
water systems. The OPs idea is the wrong one and I put him on track.

In article .com,
wrote:
You've already told the OP what your 'solution' is. I have simply
answered his question.

Because you couldn't think of anything else, as you don't know about
water systems.

And I'd guess you haven't a clue about electronics.

The OPs idea is the wrong one and I put him on track.

No you haven't. Trying to heat and store water at 80c with a standard
cylinder is a daft idea.

--
*Honk if you love peace and quiet*

Dave Plowman London SW
To e-mail, change noise into sound.

The message .com
from contains these words:

Because you couldn't think of anything else, as you don't know about
water systems. The OPs idea is the wrong one and I put him on track.

An uncanny echo of Dribble there. I am beginning to doubt they are
siblings, more likely two facets of a split personality. I wonder how
many more there are out there that aren't quite so obvious.

--
Roger Chapman

Stuart wrote:

We have a traditional hot water system that uses a storage tank for the hot
water, the heating of the water is primarily through a gas boiler with an
electrical immersion heater as back up.

What sort of boiler is it?

Conventional or condensing?

What flow temperature do you usually run it at?

How long does the current setup take to recover the water temp? What
sort of cylinder is it? i.e. what capacity and is it a normal indirect
one or a fast recovery type?

I would like to connect the electric immersion heater up, so it works when
the Gas boiler switches to heat the water. Thus reheating the water at a
much faster rate.

I have tried to adjust the thermostats so they work in tandem, but have been
unsuccessful, either the water is heated to too high a temperature or the
electrical immersion does not kick in.

Sounds like you have too much hysteresis in your stats.

I was thinking of some sort of relay device that would switch the electrical
immersion heater on when the motorised valve is switched to open, but what
sort of relay would I buy and where from.? And if this was implemented would
it still just heat the water to the same temperature as set for the gas
boiler or would the water still be overheated?

Depends on which stat you use to control what. You may get better
results by adding an additional strap on tank stat to control your
relay, and then turning up the one in the immersion so as to effectively
remove it from the equation (for all purposes other than as a safety
backup).

Also look at what cylinder temperature you are currently requesting on
the cylinder stat. It might be you could tweak it up some more to allow
more cold to be mixed with the water at the point of use.

(A higher tank temp is partly a "one shot" solution in that recovery
via the boiler will take a long time finish off the last bit of
temperature rise, since the temperature differential between primary CH
water and cylinder temp will be small toward the end of the heating
phase. It does however mean the first tank full will go a bit further)


--
Cheers,

John.

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