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Dormer Cottage, Spurgrove Lane, Little Frieth,

Nr. Henley on Thames, Bucks, RG9 6NU

Phone/Fax: 01494 882600

Koi Pond Heating Equipment

At Koi Water Garden, we are able to offer competitive prices on not only high quality koi, but also on koi related goods such as Duratech Air Source Heat Pumps, electric heaters, heat exchangers, and other accessories.

 

last updated 13th October 2016

 

 

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Heating your Pond - is it necessary? - What's the best method?

Well frankly - NO - you don't have to heat a koi pond. Koi are poikilothermic, which means their body temperature is governed by the surrounding water temperature. They are hardy 'coldwater' fish which will withstand and proliferate in a wide range of water temperatures. Koi have been known to survive temperatures of 1 Deg C (33 Deg F) up to 32 Deg C (90 Deg F) without ill effect. It is not the extremes of temperatures which seem to bother Koi, but rather the duration of any temperature extremes and rapid temperature fluctuations which can cause problems for the Koi keeper.

 

In the UK, the problems are generally not associated with extremely cold water temperatures during winter, but rather the length of our rather dreary, 'cold' and miserable winters and low water temperatures which cause problems. A Koi's immune system functions properly at temperatures over around 12.5 Deg C ( 55 Deg F). Under this and the immune system ceases to function effectively and at lower temperatures, a Koi's ability to fight diseases can be severely reduced. Unfortunately, many pathogenic bacteria and a range of parasites can survive and even proliferate at temperatures down to around 5 Deg C, meaning that your Koi are at their most vulnerable at temperatures of between 6 Deg C and 12.5 Deg C. As water temperatures in the UK can be in this range for up to 5 months of the year, you will appreciate why it is that most of the disease problems with which we as Koi keepers are faced (generally in Springtime) may be precipitated by this length of relatively cold water temperatures.

 

In addition, smaller ponds of say, 2000 gallons or less will be more prone to the affects of unstable water chemistry as the pond volume is comparatively small. Even in ponds with a larger volume but of a shallow nature can exhibit the same problems. Any water parameters which change too quickly will stress the Koi. One of these water parameters is obviously water temperature, and ideally, this should not fluctuate by more than 0.5 deg C per day. Over winter, and indeed in Spring, we may get very cold and frosty nights, but followed by sunny days, which can result in temperature fluctuations of up to 2 deg C or even more in small, unheated, shallow and uncovered ponds. The degree of temperature change obviously varies across the UK but one of the most important benefits of heating a Koi pond is the ability to achieve a stable water temperature at all times.

The objective of any heating installation is therefore not to heat the pond to high temperatures for reasons of, for example, high growth, or just to keep our koi active. It should be targeted at controlling the water temperature to avoid the temperature 'trap' or fluctuation described above.

 

In our own installations, we heat our stock (and private) ponds until Christmas time, by leaving the pond thermostats set to 16 Deg C ( 61 Deg F). This extends the Koi's Summer and keeps them feeding and growing well. From around the turn of the new year we then progressively turn down the temperature by 1/2 Deg per day until the water temperature returns to ambient levels (whereby the water temperature falls to match the surrounding average air temperature). We then give all our Koi a shortened winter for about 1/2 of January and all of February and then switch the heating on again at the beginning of March. During these cold months we allow the water temperatures to drop as low as we can , normally down to 3 or 4 Deg C. This does absolutely no harm to healthy Koi for this short period but helps to 'cleanse' the pond environment and kill off any remaining parasites or bacteria.

 This means that we are effectively giving the Koi a 10 month Summer and a maximum two month Winter. We are also only using our heating systems for around 4 -5 months of the year, and not heating at all for the two coldest months, January or February, and since we are not trying to raise our pond temperatures to ridiculously high levels, we are also reducing extra fuel bills as much as possible.

 It is an established and accepted fact that Koi live longer if given a 'natural' winter, and we do NOT subscribe to the view that Koi ponds must be heated all the year round to ensure their well being. Indeed we would go further, in that ponds that are heated all the year round must be maintained much more carefully to avoid problems as the Koi never get a period of 'rest' or inactivity and a Summer maintenance regime is absolutely vital to ensure that no problems are encountered. Weekly water changes and filter maintenance must be adhered to whilst water temperatures are elevated simply because whilst you are providing a warm comfortable environment for your Koi, you are also providing the same conditions for parasites and bacteria which can and often do multiply very quickly in ponds kept 'warm' during winter, whilst the not so vigilant Koi keeper is snuggled up in front of a log fire with ample supplies of mince pies and Brandy, completely forgetting about daily or even weekly pond maintenance tasks!

 If you do decide to heat your pond you will have a number of options, including heating using gas, oil, electricity and now electricity in the form of air source heat pumps. Whilst Gas and installations are more expensive to install, they are comparatively cheap to run.  Oil is now becoming very expensive, and the capital outlay for an oil installation is generally also much more expensive than a gas installation. Direct electric heating systems are easy and relatively cheap to install, but are the most expensive to run - and now with the introduction of air source heat pumps, you have the ability to increase the efficiency of your heating system installation by up to 400% as air source heat pumps can deliver up to 5 times the energy consumed and are now by far the cheapest method of heating your pond ( see below). However - the choice is yours!

 

To give you an idea of costs, Gas systems can cost as little as 70p per thousand gallons per day to run, whilst oil is currently around £1.00 per thousand gallons per day, and direct electric heating costs start from around £1.30p per thousand gallons per Day.

 DC inverter air source heat pumps can cost as little as 50p per thousand gallons per day. Insulating a heated pond is vital for keeping costs under control and even a simple cover made from a heat retentive material such as bubble wrap or (ideally) polycarbonate will reduce costs substantially. As an example we have halved the costs of heating our 18,000 gallons of stock ponds this year (November 2008) by covering all the ponds with triple wall polycarbonate sheet. The costs of the insulation will pay for itself in the first season. .

 

 

 

Digital Thermostats.

A necessity if you heat your pond, gives very accurate control down to + or - 0.1 Deg C resolution. Fully adjustable, weather proof (splash proof) and ideal for Gas or Oil installations. Complete with thermostat probe cable (5 metres) and power connections. LED display. Not suitable for the control of direct electric heaters.

 

 

 

Type Price
Pro-line digital £132.50
 Digital thermostat

Digital Thermostats - relay controlled.

A necessity if you heat your pond using direct electric heating, gives very accurate control down to + or - 0.1 Deg C resolution. Fully programmable , weather proof (splash proof) and can also be used for Gas or Oil installations. Complete with thermostat probe cable (5 metres) and power connections. LED display. Suitable for use with mains powered heaters up to 3kw. .

 

 

 

Type Price
Pro-line digital £205.50
 
Digital thermostat

Stainless Steel Heat Exhangers

These are made from high grade stainless steel and incorporate thermostat probe pockets and 1.5" or 2" male threaded pipe fitings.

 

Capacity/Max flow Price
60,000 btu, 900 gph £230.50
100,000 btu, 1440 gph £245.50
130,000 btu, 1860 gph £275.95
170,000 btu, 2460 gph £299.50
230,000 btu, 3300 gph £355.50
460,000 btu, 6600 gph


 
£795.00


 stainless steel heat exchanger

Floating Digital Thermometer

This super floating digital thermometer reads in Centigrade and is really neat. Solar and battery powered. Supplied with tethering cord.

 

 

 

Model Price
solar digital £17.95
 

IR Infra Red Pocket Thermometer

This super little pocket thermometer reads remotely by using Infra Red technology - just point at the water and press the button to get an accurate and instant reading of water temperature. No probe, no wires, no contact with the water. Powered by 2 x AAA batteries, the unit utilises an LCD display which reads from -50 and + 350 deg C, with a resolution of 0.1 deg C - the unit comes complete with batteries. Reads in Celsius or Farenheit.

 

Model Price
IR Pocket £19.95
 

Infra Red Thermometer

This super little pocket thermometer reads remotely by using Infra Red technology - just point at the water and press the button to get an accurate and instant reading of water temperature. No probe, no wires, no contact with the water. Powered by a lithium battery, the unit utilises an LCD display which reads in Farenheit and Celsius (Range from -10 and 100 deg C), the unit comes complete with key ring and clip so you don't lose it.

 

Model Price
TN2 £29.50
 

Pro-line Titanium pond heater systems.

These all new heater units have titanium heating elements for good resistance to chemicals, especially salt in the pond water, and therefore have a long life. Accurate to + or - 0.1 deg C the special thermostats have an internal relay that allows them to be used on a wide range of applications including gas and oil boilers as well as electric heaters up to 3kw. These units represent very good value for money indeed. To calculate the correct heater size you will need 1kw per 1000 gallons. All the units in this range can be connected to a normal domestic 13amp mains supply.

 These new Pro-line heaters also offer ultimate flexibility in that the heaters and thermostats can be used independently. Should either unit fail, they can therefore be replaced individually and systems can be upgraded from 0.5kw to 1kw to 2kw to 3kw using the same thermostat.

 

 

 

Model Price
2kw, 9 amp £365.00
3kw, 13amp £385.00
2kw, 9 amp, Element only £155.00
3kw, 13 amp, Element only £169.00
 Pro-line heater

Elecro Titanium in-line heaters.

These units have accurate digital thermostats (except Nano) and Titanium heating elements for ultimate corrosion resistance AND can accept water flow through either direction thanks to the newly designed exterior flow switch. Accurate to + or - 0.1 deg C. To calculate the correct heater you will need 1kw per 1000 gallons. Units up to 3 kw can be connected to a normal domestic mains supply. For kw ratings in excess of 3 kw, heavy duty circuits will be required. All heaters come with 1.5" female threaded end caps for connection to existing 1.5" pipe work (either solvent or pressure) IP 20 rated, will need protection from inclement weather. The smaller analgue, Nano model can be mounted either vertically or horizontally.

 

 

 

Pack Size Price
Nano 3kw, 13 amp £305.00
2kw, 9amp £529.00
3kw, 13 amp £549.00
4kw, 17 amp £580.00
6kw, 25 amp £625.00
8kw, 34 amp £679.00
 Elecro titanium in line heater

E-Eco Air Source Heat Pumps.

Air source heat pumps are fast becoming the most talked about 'new' technology, as least as far as heating Koi ponds are concerned. They are the latest form of 'green' energy efficient devices, being very economical to run . The technology has been around for many years now and in use for swimming pool heating, and latterly for domestic water and room heating, but only in the last few years have they begun to be developed and marketed with Koi ponds in mind. A normal domestic or industrial heat pump would not be suitable for use with a Koi pond, as they can be very complex and expensive to install to make them suitable, it is only in the last few years that models have been developed with Koi Ponds in mind. So we are very excited to be among the first of a handful of Koi dealers in the UK who can offer a range of air source heat pumps specifically engineered for the Koi market place. The E-Eco range are nor only super efficient, but are very competitively priced, and unusually are offered with the smaller Koi pond in mind, with models starting from 4kw output, ideal for ponds up to around 2,500 gallons (11,350 litres)

 

What is a heat pump?:- A device that converts electrical energy to kinetic to thermal energy through the use of compressed refrigerant. It works like a refrigerator in reverse. It draws heat from the air, and pumps it to the pond water. A heat pump does not create heat like a resistance heater, it extracts heat from one location and transfers it to where it is needed.

Heat pumps operate on the principle of a closed circuit similar to that used in the household refrigerator. One side is cold the other hot. For instance a refrigerator removes heat from its inside as well as from the food, and transfers it via the condenser to the outside air, which is warmed.

 

The E-Eco Heat Pumps utilise the sun’s free heat by collecting and absorbing energy from the outside air. This energy is then transferred to the koi pond water. Your existing koi pond pump circulates the water through the heater and warms the pond. The unit contains a fan that draws in outside air and directs it over the surface of the EVAPORATOR (energy collector). The liquid refrigerant within the EVAPORATOR coil absorbs the heat from the outside air and the refrigerant becomes a gas. The warm gas passes through the compressor where it is compressed to form a very hot gas, which then passes through the CONDENSOR (water heat exchanger). It is here that the heat exchange occurs as the hot gas gives up the heat to the cooler koi pond water circulating through the coil. The pond water becomes warmer and the hot gas is cooling down as it flows through the CONDENSOR coil, returns to its liquid form and, after passing through the expansion valve, the whole process begins again.

Depending upon the design of the installation and ambient temperatures, it is possible to get in excess of 5 times more heat per kw of power consumed using the latest heat pump technology. So for every 1kw of power consumed, up to 6kw of heat can be produced to heat the water.

 

Heat pumps are at least 3 times more efficient than other heating methods including gas, oil, and direct electric. Savings in terms of running costs can be as much as 70% less than for direct electric heating, and up to 40% less than oil or gas.

If you do decide to heat your pond, air source heat pumps are undoubtedly by far the most cost effective method of doing so, being economical to purchase and install when compared to gas or oil installations as well as being cheaper to run, and are way way cheaper to run than direct electric systems.

 

E-Eco Air Source Heat Pump models.

 

These models are represent the latest technology in heat pumps, and have COPs up to 5.8 (coefficient of performance) measured at 20 deg C ambient air temperature. Heat Pumps are very simple to install, just interrupt the pump flow line so that the pond water flows through the heat pump on its way back to the pond. Then just plug in and switch on.

Model E-Eco 04 E-Eco 06 E-Eco 09 E-Eco 12 E-Eco 14
Heating Capacity (kw) 4.12 5.95 8.47 11.6 13.7
Output (btu) 14,000 20,000 29,000 39,500 46,500
Max Input power (kw) 0.73 1.04 1.45 1.98 2.41
Max Current (amps) 3.4 4.8 6.5 9.1 11
Power Supply single phase single phase single phase single phase single phase
COP at 15 deg C 4.12 4.25 4.29 4.46 4.52
Recommended max pond size (gallons) 2500 4500 7250 10000 11000
Heat Exchanger Titanium Titanium Titanium Titanium Titanium
Compressor Rotary Rotary Rotary Rotary Rotary
Inlet/Outlet Connections 50mm 50mm 50mm 50mm 50mm
Nominal Flow rate cu.m/hr 1.5 2.3 3.0 4.5 5.3
Refrigerant RF410A RF410A RF410A RF410A RF410A
Dimensions L x W x H mm 770/315/585 770/315/585 953/360/605 953/360/605 953/360/605
Weight (kg) 35 40 52 67 72
Noise Level DBA 48 50 52 54 56
Price 895.00 1095.00 1295.00 1495.00 1695.00
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Duratech Air Source Heat Pumps.

In the last 3 years or so, a number of manufacturers have introduced DC inverter type air source heat pumps.

 

Inverter heat pumps have DC compressor motors with variable speed for variable performance range - this means an inverter heat pump can heat a given area (or volume of water) quicker than a conventional heat pump of similar capacity by speeding up during initial heating process.  Inverter heat pumps can provide small amounts of heating when required with minimal electrical consumption. DC electric motors are considerably more efficient than conventional AC motors, so even running at full power, they use even less electricity than AC models producing the same power.

Inverter models therefore use less electricity to operate and are highly energy efficient. The amount of heating required by a heat pump inverter will vary depending on the outdoor temperature and the current water temperature. Conventional heat pumps operate their compressors at a fixed speed and therefore deliver a fixed amount of heat/cooling power. As a result the compressor must continually stop and start to maintain temperature required in the room -i.e they are either off, or running at full power.

 

Inverter heat pumps vary the speed of the compressors delivering precise heating as required. They are able to do this because they use DC power rather than AC power to drive the compressor. When the compressor operates at high speed, the amount of refrigerant flow through the system increases the heating capacity. Alternatively, when the compressor operates at low speed the amount of refrigerant flowing through the system decreases thus decreasing the capacity. When an inverter heat pump is switched on the compressor operates at high speed in order to heat the water quickly. As the water temperature approaches the set temperature the compressor slows down maintaining a constant temperature and saving energy therefore saving money. If there is a sudden fluctuation in water temperature the heat pump senses this and instantly adjusts itself to bring the temperature back up to the required temperature.

 

So we are very excited to be among the first of a handful of Koi dealers in the UK who can offer a range of DC inverter air source heat pumps specifically engineered for the Koi market place.

What is a heat pump?:- A device that converts electrical energy to kinetic to thermal energy through the use of compressed refrigerant. It works like a refrigerator in reverse. It draws heat out of one location, and pumps it to another. A heat pump does not create heat like a resistance heater, it extracts heat from one location and transfers it to where it is needed.

Heat pumps operate on the principle of a closed circuit similar to that used in the household refrigerator. One side is cold the other hot. For instance a refrigerator removes heat from its inside as well as from the food, and transfers it via the condenser to the outside air, which is warmed.

 

The Duratech Plus Heat Pumps utilise the sun’s free heat by collecting and absorbing energy from the outside air. This energy is then transferred to the koi pond water. Your existing koi pond pump circulates the water through the heater and warms the pond. The unit contains a fan that draws in outside air and directs it over the surface of the EVAPORATOR (energy collector). The liquid refrigerant within the EVAPORATOR coil absorbs the heat from the outside air and the refrigerant becomes a gas. The warm gas passes through the compressor where it is compressed to form a very hot gas, which then passes through the CONDENSOR (water heat exchanger). It is here that the heat exchange occurs as the hot gas gives up the heat to the cooler koi pond water circulating through the coil. The pond water becomes warmer and the hot gas is cooling down as it flows through the CONDENSOR coil, returns to its liquid form and, after passing through the expansion valve, the whole process begins again.

Depending upon the design of the installation and ambient temperatures, it is possible to get in excess of 5 times more heat per kw of power consumed using the latest inverter heat pump technology. So for every 1kw of power consumed, up to 5kw of heat can be produced to heat the water.

 

What is an Inverter heat pump? An inverter heat pump uses sophisticated DC motors and electronics to monitor and match the units performance to the heat requirements - this means closer temperature control than with conventional heat pumps.

 

Heat pumps are at least 3 times more efficient than other heating methods including gas, oil, and direct electric. Savings in terms of running costs can be as much as 70% less than for direct electric heating, and up to 40% less than oil or gas.

If you do decide to heat your pond, inverter heat pumps are undoubtedly by far the most cost effective method of doing so, being economical to purchase and install when compared to gas or oil installations as well as being cheaper to run, and are way way cheaper to run than direct electric systems.

 

Duratech Air Source Heat Pump models.

 

These DC inverter models are represent the latest technology in heat pumps, and have COPs up to 6.0 (coefficient of performance) measured at 20 deg C ambient air temperature. Heat Pumps are very simple to install, just interrupt the pump flow line so that the pond water flows through the heat pump on its way back to the pond. Then just plug in and switch on.

Model Dura 7+ Dura 10+ Dura 14+ Dura 19+ Dura 22+T
Heating Capacity (kw) 7 9.8 14.3 19.6 22
Output (btu) 23,900 33,450 48,500 66,500
Max Input power (kw) 1.2 1.71 2.46 3.44 3.67
Max Current (amps) 5.2 7.4 10.7 14.95 7.1
Power Supply single phase single phase single phase single phase three phase
COP at 15 deg C 5.3 5.25 5.3 5.3 5.5
Recommended max pond size (gallons) 5000 7000 10000 13800 15500
Heat Exchanger Titanium Titanium Titanium Titanium Titanium
Compressor Rotary Rotary Rotary Scroll Scroll
Control DC Inverter DC Inverter DC Inverter DC Inverter DC Inverter
Inlet/Outlet Connections 50mm 50mm 50mm 50mm 50mm
Nominal Flow rate cu.m/hr 3 3 4.5 6 14
Refrigerant RF410A RF410A RF410A RF410A RF410A
Dimensions L x W x H mm 905/420/650 905/420/650 905/420/650 1200/470/850 660/660/960
Weight (kg) 55 60 77 99 109
Noise Level DBA 51 51 51 54 57
Price 1475.00 1995.00 2495.00 2995.00 on app
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