77
Once you have made the connections in accordance with page 7 be sure to seal and pressure test
to at least 1 and a half times the proposed working pressure of the system (suggested working
pressure 3 - 4 Bar), normal testing pressure will be 6.5 Bar. Once the system has been tested
connections can be taken from the roof space to the proposed location of the double pump station.
Be sure to use 22mm Copper Pipe, and Compression fittings. If required using a small amount of
sealing compound on the outside of the olive is suggested in order to give a good seal for glycol.
Important: Plastic pipe should NEVER be used.
The use of the correct insulation is critical. Normal central heating insulation will melt and become
brittle at the very high solar generated temperatures in the system. Insulation materials must endure
the highest occurring temperature, which will be more than 170
o
C near the collector.
When the insulation is to be used outside it must be:
• Resistant to temperatures up to 170
o
C
• Must have a flexibility in - 30
o
C conditions
• Resistant to air pollution
• Resistance to UV radiation
• Resistance to pests, such as mice and birds that may eat it
• Insulation should be externally sealed to prevent it carrying moisture.
RM Solar carry a range of suitable insulation in stock that can be purchashed through your plumbers
merchant.
The glycol is used as heat exchange fluid with a very low freezing point, already pre-mixed to allow
give a freezing point of -20
o
C. RM Solar only recommend using the glycol supplied by ourselves and
that comes as part of the kit purchased. RM Solar glycol has the following properties:
• Premixed to give protection down to -20
o
C (Do not dilute further).
• Contains anti-corrosion inhibitors for pipe protection
• Glycol is a low toxic polypropylene product approved for use in solar systems by all major
countries including the USA & EU
• The glycol has a notably more intensive creeping property than water
• Glycol is not compatible with Zinc, so pipes with internal zinc galvanising should not be used
• As with all chemicals, normal precautions should be taken in handling the glycol to prevent
ingestion and delivery into the water system.
Important
Under no circumstances should any ethylene based glycol be used in solar systems. The material
safety data sheet for the RM Solar glycol is available from RM Solar on request.
Section 5 - Piping S
ystem, I
nsulation & Gly
col
System Piping
Insulation
Glycol
