my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of warranty,
i think it is made by drall but i can't find any info on the company,
anyone got any suggestions or experience of building pond heating system?

In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on the
company, anyone got any suggestions or experience of building pond
heating system?

What's the reason for having a pond heater ?

--
geoff

raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
the company, anyone got any suggestions or experience of building pond
heating system?

What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.

all it is is water into a tube that contains a submersible heater, kind
like an immersion heater, with a seperate control box that controls the
temp via a thermostat that is at the side of the element.

all i need to achieve is the temp controlled by a thermostat to switch
the heat on and off, seperate if needs be to the original heater part,
maybe some kind of inline 'box' after the heater.

any help would be grateful

Gav

Gav ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote:
raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
the company, anyone got any suggestions or experience of building pond
heating system?

What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.

Err, no.
They do just fine with a nice deep pond (~1m or so), even if the top
freezes, the bottom will generally stay at 4C, due to the thermocline.

(~60 fish in 2m deep pond, in scotland, over a couple of winters, and
none have died, despite occasional 10cm thick ice.)

Ian Stirling wrote:
Gav ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote:
raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
the company, anyone got any suggestions or experience of building pond
heating system?
What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.

Err, no.
They do just fine with a nice deep pond (~1m or so), even if the top
freezes, the bottom will generally stay at 4C, due to the thermocline.

(~60 fish in 2m deep pond, in scotland, over a couple of winters, and
none have died, despite occasional 10cm thick ice.)
i don't keep the things myself, i'm into tropical and can handle thier
temp changes and care well but cold water fish are a mystery to me, all
i know is what the inlaws tell me. if they dont need heat then they are
wasting thier cash on leccy etc so maybe i can convince them just to buy
one of the heaters that just stop ice for air and waste gas??????

Gav ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote in
. uk:

if the top
freezes, the bottom will generally stay at 4C, due to the
thermocline.

(~60 fish in 2m deep pond, in scotland, over a couple of winters, and
none have died, despite occasional 10cm thick ice.)

i don't keep the things myself, i'm into tropical and can handle thier
temp changes and care well but cold water fish are a mystery to me,
all i know is what the inlaws tell me.

Well, *my* inlaws have kept koi and other fish for ages in a completely
unheated pond, about a meter deep, but the earlier pond was shallower.

They died of herons, fin rot, knob rot, scabies, black death, and old age,
but never of hypothermia.

mike

In message , Gav writes
Ian Stirling wrote:
Gav ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote:
raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms
the thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
the company, anyone got any suggestions or experience of building
pond heating system?
What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.
Err, no.
They do just fine with a nice deep pond (~1m or so), even if the top
freezes, the bottom will generally stay at 4C, due to the thermocline.
(~60 fish in 2m deep pond, in scotland, over a couple of winters,
and
none have died, despite occasional 10cm thick ice.)
i don't keep the things myself, i'm into tropical and can handle thier
temp changes and care well but cold water fish are a mystery to me, all
i know is what the inlaws tell me. if they dont need heat then they are
wasting thier cash on leccy etc so maybe i can convince them just to
buy one of the heaters that just stop ice for air and waste gas??????

Sounds like a plan

--
geoff

Gav ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote:
Ian Stirling wrote:
Gav ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote:
raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
the company, anyone got any suggestions or experience of building pond
heating system?
What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.

Err, no.
They do just fine with a nice deep pond (~1m or so), even if the top
freezes, the bottom will generally stay at 4C, due to the thermocline.

(~60 fish in 2m deep pond, in scotland, over a couple of winters, and
none have died, despite occasional 10cm thick ice.)
i don't keep the things myself, i'm into tropical and can handle thier
temp changes and care well but cold water fish are a mystery to me, all
i know is what the inlaws tell me. if they dont need heat then they are
wasting thier cash on leccy etc so maybe i can convince them just to buy
one of the heaters that just stop ice for air and waste gas??????

You don't really need a heater for that.
Just a bubbler.
The bubbler goes under a 30cm bit of polystyrene.
You don't want to stir the water down deep, as then you break up the
thermocline (water gets most dense at 4C, so convection stops there, and
you get a layer of 4C water at the bottom). Stirring the bottom with an
airstone or whatever, can result in a temperature of under 4C, as can a
very shallow pond.

In message , Gav writes
raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms
the thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
company, anyone got any suggestions or experience of building pond
heating system?
What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.

all it is is water into a tube that contains a submersible heater, kind
like an immersion heater, with a seperate control box that controls the
temp via a thermostat that is at the side of the element.

all i need to achieve is the temp controlled by a thermostat to switch
the heat on and off, seperate if needs be to the original heater part,
maybe some kind of inline 'box' after the heater.

any help would be grateful

Well, Koi are cold blooded creatures and survive quite happily over
winter without any heating

My fish seem to have come through an unheated winter .. as usual

I think pond heating is a) expensive and b) unnecessary

--
geoff

raden wrote:
In message , Gav writes
raden wrote:
In message , Gav writes
my inlaws have asked me to have a look at thier pond heater, semms
the thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of
warranty, i think it is made by drall but i can't find any info on
company, anyone got any suggestions or experience of building pond
heating system?
What's the reason for having a pond heater ?

you want the long or short answer?

they(alledgedly) require 10 degrees c, koi that is.

all it is is water into a tube that contains a submersible heater,
kind like an immersion heater, with a seperate control box that
controls the temp via a thermostat that is at the side of the element.

all i need to achieve is the temp controlled by a thermostat to switch
the heat on and off, seperate if needs be to the original heater part,
maybe some kind of inline 'box' after the heater.

any help would be grateful

Well, Koi are cold blooded creatures and survive quite happily over
winter without any heating

My fish seem to have come through an unheated winter .. as usual

I think pond heating is a) expensive and b) unnecessary

probably but you know what the jones's have! i will convince them it
aint needed!

thanks for input

Gav wrote:
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of warranty,
i think it is made by drall but i can't find any info on the company,
anyone got any suggestions or experience of building pond heating system?

You dont tell us much about it! All I can usefully say is if its not
solar, make a solar one instead. Pool heating is one of the few apps
where solar energy can pay back _very_ well indeed. Hosepipe panel etc

NT

wrote:
Gav wrote:
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

simple answer buy a new one, but this unit is only just out of warranty,
i think it is made by drall but i can't find any info on the company,
anyone got any suggestions or experience of building pond heating system?

You dont tell us much about it! All I can usefully say is if its not
solar, make a solar one instead. Pool heating is one of the few apps
where solar energy can pay back _very_ well indeed. Hosepipe panel etc

NT

dunno if solar would be appropriate as the temp needs to be above 10
degrees c all year round, including night time.

if you think a solar system would work please let me know in more detail
how to build such a system and keep in mind this is an ornamental garden
and not a science museum. they like the discreet system and 'it just
works' attitude(the in-laws that is not the fish!)

Gav wrote:
wrote:
Gav wrote:
my inlaws have asked me to have a look at thier pond heater, semms the
thermostat is not working and i can't find a replacement part.

dunno if solar would be appropriate as the temp needs to be above 10
degrees c all year round, including night time.

if you think a solar system would work please let me know in more detail
how to build such a system and keep in mind this is an ornamental garden
and not a science museum. they like the discreet system and 'it just
works' attitude(the in-laws that is not the fish!)

OK, a little info for a start, see if any of this lines up with what
you want.

Pool/pond solar heaters are very efficient because they heat water to a
very low temp, in contrast to DHW solar heating. Theyre also cheap to
make, at under £100 the lot. The usual recommendation is a lot of
hosepipe in a big flat coiled pancake shape, preferably with gaps
between the turns and polythene on top. Plus a pump. This wont look
good in an onrnamental situation though, would need something more
prettified. Acid etched glass could be used to put a pretty front on
such a heater.

Since you need it in winter, the power output will be a few hundred
watts per square metre, rather than a good double that in summer. It
can deliver this as long as you have daylight, so by knowing the power
and run time of the present heater you can work out what you need to
maintain 10C.

Day/night temps: the water acts as storage, its just heated in the day.
If you need 10C at night, you might need 10.5 (etc) in day to keep it
above 10.

Hosepipe pancakes are max output per metre of hose when the turns are
spaced out a bit. But a glass cover will be the highest cost part, so
to maximise return per purchase cost, pipe turns close together.

To maximise temp rise, reflective mylar sheet behind the pipes with
pipes spaced out with 1 pipe dia space between each turn. Sun that
misses the pipes will reflect off the mylar onto the pipe, and you get
at least some concentration effect. Concentrated panels using low cost
plastic pipes are best covered or hinged and swung out of the full sun
in summer.

Panel is arranged so it drains at least semi-empty when the pump stops,
since it will see freezing day in day out. It will freeze happily as
long as it has air in as well as water.

Pipe: most colours work ok, best to avoid red or orange.

Pump: keeping pump size and rate low minimises electricity use. Use
thermostat to turn pump on/off. You also need a thermostat on the panel
so the pump can only come on once the panel starts to warm up. Set this
to just over your target temp, so maybe 15C. It is common for people to
use unnecessarily high power pumps, eg hundreds of watts. If your temp
rise thru the panel is under 10C, you can use lower power pumping and
save your money. 30w of pump is more the ballpark.

A low cost way to boost panel output is to use something reflective to
put more sunlight onto it. Matt white paint looks nicer than mylar
coated plastic film. Sun can be reflected direct into the pond as well,
as probably the cheapest type of solar pond heating.

Set pond target temp to above your wanted minimum to allow for a snowy
night plus a dull dark day etc.

If you wish you could keep the present heater as well as backup in case
anything fails, and as 2 systems backing each other up makes a very
much more reliable combination than one alone. And its there already.

alt.solar.thermal is all about this sort of thing, and often assist
people work out how much panel area they need, and how much pump power.

Thermostat repair: most common fault is simply burnt switch contacts.
These can be tidied up with _very_ fine sandpaper, or even go-easy use
of a rats tail file. Note they may need temp setting readjustment after
handling.

An open pond with snow falling in it is going to take a lot of heating.
partial covering would really help.

What the solar panel does is use a little electricity to capture a lot
of sunlight & skylight heat. Hosepipe panels have excellant payback
figures, these things can pay their low cost back many times over. The
systems are very simple, and if you calculate each number before
building you can get impressive performance.


NT