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Stainless steel stands suitable for flat roof or ground mounting of panels.
For fixing collector to roof. Available in two
lengths, stainless steel bolts 7mm dia with M8 thread at one end and coach screw thread at
the other. The maximum distance from top of the rafter to roof surface
may be no more than 50mm for the short bolts or 90mm for the long bolts.
Includes 2 nuts, two stainless washers and two rubber washers. See here for
installation instructions for both fitting methods.
180mm overall length
For fixing collector to roof. Stainless steel strap
1m x 27mm punched with 9mm holes on 20mm centres. Includes 2 M8 x 20 bolts
and nuts per strap to fix to the panel frame. These are an alternative
to the fitting bolts above.
Lead or aluminium "slates" which can be formed to match the shape of the tile, incorporating a high temperature silicon boot (suitable for temperatures between -60C and +240C) with provision for a sensor wire. Makes for a neat job, resolves weatherproofing issues, and keeps the building inspector (should you be involved with one) happy. Recommended for roof pitches up to 45 degrees and pipe diameters between 5 and 40mm, suitable for both copper and corrugated stainless steel pipe. One flashing per pipe required, except for twin entry version..
Lead flashing 410mm x 490mm
Aluminium flashing 450mm x 600mm
Twin entry aluminium flashing 450mm x 600mm
Spare Tubes assemblies are available from stock. They include the internal fins and heat pipes, and are ready to slot into the manifold.
These are the copper pipes used in the centre of the collector tubes. They are sealed and contain fluid at low pressure which vaporizes (boils) at low temperature. When placed sloping upwards, the vapour rises to the top of the tube and transfers heat to whatever is attached to the top, then condenses and runs back down the tube to restart the cycle. Useful for science projects and various applications such as using heat from a compost heap. Suitable for moving heat at temperatures between about 40°C and 220°C
Differential Temperature Controllers
Solar controllers compare the temperature of the water in
the collector header with that in the hot water cylinder. If the
temperature of the former exceeds that of the latter by more than a preset
amount, typically 6°C,
it switches on the circulation pump. We stock controllers from market
Basic differential controller with maximum temperature
setting to switch off pump in the event of overheating.
Controller with graphical display and ability to operate
diverter valve heat dump circuit to avoid overheating.
As BS3 with additional ability to control variable speed
Resol BS Plus (formerly designated BS Pro)
Adds the facility to control two pumps for East/West
panels, used when only East or West facing collectors can be installed (the East
facing panel is used in the morning and the West facing in the afternoon).
Includes 10 sensor inputs and 6 relay outputs, variable
pump speed control and East/West collector configuration. Most usually
specified for systems with 2 stores, typically a hot water cylinder and a
preheat cylinder, used when there is a requirement to retain the original
Includes 13 sensor inputs and 7 relay outputs, of which up
to three are for variable pump speed control. Supports 30 layout
schemes including East/West collectors with up to 3 stores or a single collector
field with up to 4 stores.
Device to prevent voltage surges on the sensor lines
caused by nearby lightning damaging the controller. Placed in the cable
between the collector sensor and controller.
Additional sensors, all PT1000 thermistors
FKP6 This is the sensor supplied with the Resol
controllers to install in the collector manifold, with a high temperature
silicon insulated cable.
FRP6 As supplied for temperature sensing at the hot
FRP21 Sensor with flat end and pipe clip, for
sensing the temperature of fluid in a pipe.
These allow accurate power delivery figures to be derived, by combining flow volume and temperature change figures.
Max flow 600litres/hr. 2 x 3/4" BSP male
connections. Readout in m3, and signal output for automatic
Note: Flowcon A pump stations have been discontinued, and replaced with the Flowcon AS
A pump station comprises a number of components required in a
solar circuit assembled in a neat insulated package. Flowcon AS pump
stations include a flowsetter, pump, differential temperature controller, non
return valve, pressure relief valve, pressure gauge, and fill and drain valves.
Flow direction is upwards, and connections are 3/4" BSP female for the flow,
return and pressure relief valve output, 3/4" BSP male and 1/2" BSP female
combined for the fill and drain valves, and 3/4" BSP male for an additional
connection which may be used for an expansion tank or part of a heat dump
circuit etc, or may be blanked off.
Resol Flowcon AS
ITT Lowara EBV 15-1/65 low energy 230V bronze circulation
pump. These super pumps have a variable power setting of 2 - 8W and are
suitable for closed loop solar circuits. Maximum continuous temperature
built in electronic temperature protection shuts the pump down at 125°C.
*The taps are spurred off the hot water loop. There will be a small amount of cold water in the spur which will cause a second or two delay before the water runs hot.
1/2" BSP female connections. Includes non-return valve.
£115 + VAT (£138)
12V DC Equipment
It is possible to use a 12V pump connected to a photovoltaic (pv) panel instead of using 230V equipment. This has the advantage of not using any (albeit a small amount of) mains power. Two strategies are possible. The first is to connect the circulating pump directly to the pv panel. The principle here is that when the sun shines, the pump will run and (hopefully!) the water in the collector will be hotter than the water in the cylinder (because the sun is shining). An alternative approach is to use a 12v differential temperature controller and connect via a charge controller and battery, which will give better control, but be more expensive. Don't make the mistake of undersizing the pv panel. Bear in mind that the quoted output is always a peak figure for full sun, which as noted elsewhere on this site, may occasionally not be the case in the UK.
BP Solar SX30U pv collector
£160 + VAT, (£192.00)
Laing D5 SOL-38/7B Ecocirc low voltage pump.
Automatic voltage selection in range 8 - 24V. Minimum startup power 1W,
max power consumption 22W, current .25 - 1.46A. Note that this pump is
designed to be connected directly to a pv panel, it incorporates firmware which
deals with a fluctuating supply. The pump checks the power supply
characteristics every 3 seconds, and adjusts its speed accordingly.
Laing D5 vario-38/700 B low voltage pump. Automatic voltage selection in range 8 - 24V. This pump is for stable regulated power supplies.
£ 136.45 + VAT (£163.74)
Resol Deltasol B 12v differential temperature controller.
Similar to the Resol BS3 in specification, but 12V.
Used to accommodate thermal expansion of the solar fluid.
Solar expansion tanks have a membrane which can withstand a higher temperature
than regular expansion tanks. Domestic installations usually require an 18
litre tank. Connection 3/4" BSP male.
Fitting Kit comprising bracket, fixing screws, 500mm flexible
stainless steel hose with 3/4" BSP female connection at both ends, and quick release valve
(3/4" BSP male/female) (which allows removal of the
expansion vessel without draining the solar circuit).
Solar Fluid (Antifreeze Solution)
Ready mixed propylene glycol based antifreeze
solution. This is used neat, and 10 litres is sufficient for typical domestic
installations. See here for more information
and details on
Thermal Transfer Paste
Tube of thermal transfer paste as supplied with the solar collectors. Used to improve the thermal connection between the heat pipe and collector manifold.
£3.00 + VAT (£3.60)
Valves & Fittings
Resol VA22 2 port high temperature motorised valve. 3/4" BSP female connections.
Eco-nomical 3 port high temperature motorised ball valve.
No power consumption when heat dump not in use. 1/2" BSP female connections.
Thermostatic mixing valve.
Allows a higher temperature in the hot water cylinder by mixing the output with
cold water to a safe level. Effectively increases the capacity of the hot
water cylinder. Adjustable temperature. Max input temperature 100°C.
Three compression fittings for connection to copper. Note that the maximum hot/cold or
cold/hot pressure ratio is 2:1.
28mm compression connections, larger valve for higher flow
Automatic high temperature air bleed valve, to be fitted
at the highest point of the solar circuit, usually on the roof next to a panel.
3/8" BSP connection.
Automatic air scoop. This is
a device which filters out micro air bubbles from the solar fluid and ejects
them via a high temperature automatic air vent which is included in the item.
This does not need to be fitted at the highest point of the circuit, and may
obviate the need for the external air vent. The belt and braces approach
is to fit them both. Fits in horizontal pipe run via two 3/4" BSP female
High temperature isolating valve for use with automatic air vent. Two
3/8" BSP connections, one male, one female.
Pressure relief valve, 6 bar
Fill and drain blocks. Makes filling the solar circuit easier. Comprise 3 high temperature valves, 2 to air and one in the solar circuit between them. Close the solar circuit valve, open the others, fill through top one. When fluid emerges from lower valve close it, open the solar circuit valve and bleed and pressurise the circuit. Already included with our Flowcon pump stations.
PAW monobloc fill and drain valve block.
15mm compression fittings to the solar circuit, fill and drain valves with 15mm
OD barbs, 1/2" BSP female threads and 3/4" BSP male threads, and blanking caps.
Eco-nomical built up fill and drain block. 15mm
compression fittings to the solar circuit, fill and drain valves with 1/2" BSP
Flowmeter/setter 2-8 litres/min. Two 15mm
Non return valve. 1/2" BSP female threads.
15mm-22mm reducing compression fitting, used on return
side of collector
15mm compression to 3/4" male BSP, for connecting 15mm
pipework to pump station, air scoop etc.
22mm compression to 3/4" male BSP, for connecting 22mm
pipework to pump station, air scoop etc.
15mm straight compression coupling
22mm straight compression coupling
15mm elbow compression coupling
22mm elbow compression coupling
Equal T compression fitting 15 x 15 x 15mm
Equal T compression fitting 22 x 22 x 22mm
Reducing T compression fitting 22 x 15 x 15mm (branch is
Unequal T fitting. One 22mm and one 15mm compression
fitting with a 3/8BSP T leg. Use on feed side of collector to connect 15mm
pipework to 22mm collector manifold inlet with connection to automatic air vent.
PTFE Tape reel
Flat plate heat exchanger, 4 x 3/4 BSP male connections, 5kW, 190 x 60 x 60mm, max pressure 12 bar. Suitable for use as external heat exchanger for solar loop.
£42.00 + VAT (£50.40)
Swimming Pool Heat Exchangers
Because chlorinated pool water attacks the copper manifold in the solar collector, it is recommended to use an indirect system with a heat exchanger. We offer Bowman cupro-nickel purpose built solar pool heat exchangers, incorporating thermostat pockets.
Bowman 4825-5 heat exchanger, suitable for pools up to
91000 litres, 20000 gallons. Connection to the solar circuit via two 3/4 BSP female connectors, and to the pool water circuit via two
11/2" BSP female connectors. For larger pools, please contact us.
Preinsulated with Armaflex HT, comprises feed and return pipes in corrugated stainless steel, insulation, and sensor wire. The two pipes are joined by the insulation, but easily separated where required. This is used in place of copper pipe, and is generally favoured by professional installers because of its speed of installation and reduced possibility of leaks (no pipe bending, fewer joints). No special tools are required to make the joints. Nominal ID 16mm, insulation thickness 14mm. Stocked in 10m coils (20m of pipe, 10 feed and 10 return). Other lengths available on request.
10m coil Armaflex Duo Solar DN16
Fittings for Armaflex Duosolar (note that fitting are sold singly, 4 are required for all pipe ends in one coil).
To connect a single pipe to itself
To connect a single pipe to 3/4" BSP female, eg to a
Flowcon pump station
To connect a single pipe to 1/2" BSP female
To connect a single pipe to 22mm copper via compression
To connect a single pipe to a 22mm compression fitting.
Used to connect
T connector for 3 DN16 pipes, as for a heat dump circuit
Armaflex HT foamed HDPE high temperature pipe insulation from Armacell. This is a top quality German product designed for the high temperatures that can be produced by evacuated tube collectors. The pipe insulation is supplied in 2m unslit tubular form, either slip it over your pipe work as you go, or slit it yourself with a sharp blade. We stock Armacell high temperature adhesive for joints and seams, resulting in a tidy job. Good for 150°C and waterproof and UV resistant (can be used outside without additional protection). Thermal conductivity at 40°C 0.045W/mK. We stock it for 15mm and 22mm pipe in 13 and 19mm wall thickness.
Five litre pump up sprayer for introducing the solar fluid
into the system. Includes adaptor to fit pump stations or fill/drain
blocks. Includes original lance, so may also be used as a garden sprayer.
Power filler/flusher, quickly fills and removes air from the solar circuit. Solid German built professional tool with welded steel chassis, self priming centrifugal pump pump and large fluid reservoir.
£465.00 + VAT (£558.00)
Hot Water cylinders
We suggest you deal directly with the manufacturer for solar hot water cylinders (mainly because we have no room here to stock them!).
Companies which will deal with individuals
and are knowledgeable in the solar field are:
Newark Copper Cylinder Co Ltd
Send mail to
SW@eco-nomical.co.uk with questions or
comments about this web site.