FITTED EQUIPMENT
115
The glycol mixture should be changed every
second year, since its ability to protect against
corrosion, for example, will deteriorate. The
glycol content should be checked before
topping up with new liquid. This will ensure
that the concentration of glycol in the mixture
is not too high.
If the fluid level in the expansion tank falls for
reasons other than evaporation, please check
all joints, drain cocks and bleeder screws to
ensure that they are not leaking. If the glycol-
water mixture leaks out, rinse with water and
wipe up.
Never allow the heating system to stand empty
of glycol.
Filling the system with glycol fluid
Note:
Any vessels used to carry the fluid
must be spotlessly clean and the pipes in
the system must be free of contamination.
This will prevent the growth of bacteria in the
system.
The system is filled through the expansion
tank, either manually or using the Alde filling
pump which both tops up and bleeds the
system. For manual filling, unfasten the
circulation pump nut (R) and lift the pump (S)
out of the tank. Slowly pour the glycol mixture
into the tank. Bleed the system.
Top up with more liquid if the level has fallen
after bleeding. Bleed a newly filled system
regularly during the first days the heating
system is in operation.
- MAX
- MIN
R
S
Types of glycol
Various types of antifreeze (as used in car
radiators) are available from service stations,
car accessory shops and on line retailers and
these types of antifreeze can be used to top
up or replace the heating system fluid in the
Alde heating system.
Frost and corrosion damage are not covered
under warranty, so it is important that the
type purchased contains corrosion inhibitors
suitable for use with aluminium systems.
Always check the label, ask the retailer for
advice, or check with your supplying dealer
if unsure. Please note the corrosion inhibitor
will have a limited life, and after it expires, the
system will have no corrosion protection.
The fluid will usually be named as Ethylene
glycol, but may also be described as
monoethylene glycol, MEG, ethanediol, or
G12++. There is no industry standard for
the colour of the antifreeze, but as a general
guideline it indicates the type of corrosion
inhibitor:
Blue, Green
- Silicate inhibitor, usually offering
2-year corrosion protection
Red, Orange -
OAT inhibitor, usually offering
5-year corrosion protection
Purple, Magenta -
G12++ Silicated OAT
inhibitor, usually offering 5 year corrosion
protection
It is important that antifreeze containing Silicate
inhibitor (Blue or Green) is not mixed with
antifreeze containing OAT inhibitor (Red or
Orange). To guarantee compatibility, there are
two options:
1. Match the colour, taking care to also check
the label on the antifreeze bottle, i.e. if the
system is filled with blue silicate-containing
antifreeze, top up with blue silicate-
containing antifreeze.
2. Use G12++ antifreeze which is compatible
with any of the other types of inhibitor
described.
