Burnham FREEDOM 101008-01R1-2/07 - Manual (Page 48)

48
WATER QUALITY AND BOILER WATER ADDITIVES
IMPORTANT NOTE
This boiler is equipped with an aluminum heat exchanger that can be seriously damaged by failure to follow
the following guidelines:
1) Flush the system before connecting the boiler y g - In a replacement installation, fl ushing the system will remove r
sediment, solder fl ux, and traces of old boiler additives. Even if the system is new, do not omit this step - new
systems will contain solder fl ux and may even contain sediment.
2) Make sure that the system is tight y g - t This is the single most important guideline. Tap water contains dissolved
oxygen which causes corrosion. In a tight system, this oxygen comes out of solution and is quickly removed
from the system through the automatic air vent. The system then remains essentially free of oxygen. If the
system is not tight, however, frequent additions of make-up water can expose the heat exchanger to oxygen on
a continuous basis. In addition, frequent additions of hard make-up water can cause calcium deposits to collect
in the heat exchanger, causing severe damage.
To minimize additions of make-up water:
• Inspect the system thoroughly for leaks before placing it in service.
• If the system includes underground piping, or other piping in which a leak might go undetected, consider
isolating the boiler from the system with a heat exchanger. Alternatively, consider installing a water meter
in the fi ll line to record additions of make-up water.
• Make sure that the expansion tank is properly sized and in good condition. If it is not, the relief valve may
open frequently, resulting in regular additions of make-up water.
3) Radiant Tubing and Oxygen Barriers g yg - Even if the system is tight, oxygen can be introduced into the system
through some types of non-metallic tubing used in radiant or snow melt systems. Other non-metallic tubing is
equipped with an oxygen barrier to prevent migration of oxygen into the water. If the boiler is to be installed in
a system containing non-metallic tubing without an oxygen barrier, it must be isolated from the boiler with a
heat exchanger as shown in Figure 9.10.
4) Antifreeze - Do not use antifreeze unless absolutely necessary. If antifreeze must be used, the only permitted
antrifreezes are:
• Fernox Alphi-11
• Fernox CHP in virgin propylene glycol (available from U.S. Boiler)
If either of the above antifreezes are used, test the boiler water on an annual basis to ensure that the antifreeze
remains non-corrosive. This is done with Fernox test kit I-TK (available from U.S. Boiler).
5) Other Antifreezes and Boiler Additives - Do not add other additives unless they are specifi cally approved in
wiring by U.S. Boiler for use with this boiler. This includes other “aluminum safe” antifreezes.
6) System PH y - Maintain the PH in the system between 6.5 and 8.5.