Greenheck Fan 470658 MSX Maintenance - Fall, Winterizing Chilled Water Coils, Blowing-OutCoils

Maintenance - Fall

Evaporative Coolers

The water should be shut off and all the lines drained when the outside temperature drops below 45°F.

Remove drain plugs for the winter.

Clean all interior parts of any mineral deposits or foreign materials that may have built-up during the cooling season.

Replace any worn or non-functioning parts.

Winterizing Chilled Water Coils

During the winter, chilled water coils need to be protected against freezing. Greenheck recommends protecting the coils by either blowing-out the coils or by flushing the coils.

Blowing-Out Coils

1.Close valves on the supply and return lines.

2.Open drain valves and/or drain plug. Remove vent plug to allow coil to drain faster.

3.After coil is fully drained, connect a blower to the caps. Do not connect the blower to the air vent or drain plug.

4.Close the vent plug on the header that the blower is connected to. Open the drain valve or cap on the other header.

5.Turn on blower for 30 minutes. Place mirror at discharge. If the mirror fogs up, repeat procedure until no fog appears on the mirror.

6.After drying the coil, wait a few minutes then repeat Step #5.

7.Leave drains open and do not install plugs until beginning of cooling season.

Flushing Coils

Greenheck recommends the use of inhibited glycol (such as propylene or ethylene) to flush water coils to protect against freezing. Additionally, the use of inhibited glycol provides corrosion protection.

The table below indicate the percentage of glycol required to prevent freezing in a coil at a given outdoor air freeze point. Completely fill coil with solution. Drain coil. Residual glycol fluid per these concentrations can be left in the coil without concern of freezing. Recovered fluid can be used to flush other coils.

Percent of	Freeze Point		Percent of	Freeze Point
Ethylene			Propylene
Glycol	°F	ºC	Glycol	°F	ºC
by Volume			by Volume
0	32	0	0	32	0
10	25	-4	10	26	-3
20	16	-9	20	19	-7
30	3	-16	30	8	-13
40	-13	-25	40	-7	-22
50	-34	-37	50	-28	-33
60	-55	-48	60	-60	-51

36 Model MSX Make-Up Air ®