10 Start-up
Check/control water chemistry
CAUTION Do not use
Damage to elastomer seals and gaskets in the system could occur, resulting in substantial property damage.
Hardness less than 7 grains
1.Consult local water treatment companies for hard water areas (above 7 grains hardness).
Chlorine concentration less than 200 ppm
1.Do not fill boiler or operate with water containing chlorine in excess of 200 ppm.
2.Filling with chlorinated fresh water should be acceptable since drinking water chlorine levels are much lower.
3.Do not use the boiler to directly heat swimming pool or spa water.
Test/replace freeze protection fluid
1.For systems using freeze protection fluids, follow fluid manufacturer’s instructions.
2.Freeze protection fluid must be replaced periodically due to degradation of inhibitors over time. Follow all fluid manufacturer’s instructions.
Freeze protection (when used)
1.Determine freeze protection fluid quantity using system water content, following fluid manufacturer’s instructions. Boiler water content is listed on page 6. Remember to include expansion tank water content.
2.Local codes may require a backflow preventer or actual disconnect from city water supply.
3.When using freeze protection fluid with automatic fill, install a water meter to monitor water makeup. Freeze protection fluid may leak before the water begins to leak, causing concentration to drop, reducing the freeze protection level.
4.The freeze protection set points may be lowered when freeze protection fluid is used (see the Knight Wall Mount Service Manual).
Fill and test water system
1.Fill system only after ensuring the water meets the requirements of this manual.
2.Close boiler drain valve and manual air vent.
3.Fill to correct system pressure. Correct pressure will vary with each application.
a.The minimum cold water fill pressure for a residential system is 12 psi.
b.Pressure will rise when boiler is turned on and system water temperature increases.
Installation & Operation Manual
4.At initial fill and during boiler startup and testing, check system thoroughly for any leaks. Repair all leaks before proceeding further.
WARNING Eliminate all system leaks. Continual fresh makeup water will reduce boiler life. Minerals
can build up in the heat exchanger, reducing heat transfer, overheating the heat exchanger, and causing heat exchanger failure.
Purge air from water system
1.Purge air from system:
a.Connect a hose to the purge valve (see purge/drain valves, in piping diagrams on pages 38 through 47). Route the hose to an area where water can drain and be seen.
b.Close the boiler or system isolation valve between the purge valve and fill connection to the system.
c.Close zone isolation valves.
d.Open
e.Open purge valve.
f.One zone at a time, open the isolation valves. Allow water to run through the zone, pushing out the air. Run until no noticeable air flow is present. Close the zone isolation valves and proceed with the next zone. Follow this procedure until all zones are purged.
g.Close the
h.After the system has operated for a while, eliminate any residual air by using the manual air vents located throughout the system.
i.If purge valves are not installed in the system, open the manual air vents in the system one at a time, beginning with the lowest floor. Close the vent when water squirts out. Repeat with remaining vents.
2.Open other vents:
a.Starting on the lowest floor, open air vents one at a time until water squirts out.
b.Repeat with remaining vents.
3.Refill to correct pressure.
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