AERCO CXT-E Retrofit Kit - Manual (Page 11)

ECS and CXT-E Retrofit Instructions Kit # 27004-TAB
Technical Instruction Document TID-0141_0A
12/30/2014 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288 Page 11 of 76
2.1 ISOLATING WATER HEATER
To isolate the Water Heater from all facility energy sources (steam, water, electrical power),
proceed as follows:
1. Disconnect and Lock-Out/Tag-Out external AC power supplied to the Control Box and any
other devices connected to the Heater.
2. Using a voltmeter, check to ensure that all incoming voltage readings are zero Before
continuing.
3. If the Heater is equipped with a Pneumatic Control Valve Actuator, close the valve supplying
air inlet pressure to the Pneumatic Controller.
4. Close all stop valves in the Steam Inlet and Condensate Outlet lines. On water-to-water
systems, do not rely on the Boiler Water Out Check Valve to stop the flow of water.
5. On the water-side, close the stop valves in the following order:
(a) Hot water outlet line
(b) Recirculation line
(c) Cold water inlet line
6. Carefully open the Relief Valve located on the Top Head to relieve pressure in the Heater
Shell. Water should stop flowing from the valve within one minute. If water continues to
flow from the Relief Valve, one of the water stop valves is not securely closed.
2.2 DRAINING WATER HEATER
Allow the Water Heater to cool sufficiently prior to draining the unit. When sufficiently cooled, drain
as follows:
1. After ensuring there is no pressure build-up in the Heater Shell (para. 2.1, step 6), block
open the Relief Valve in the Top Head to avoid creating a vacuum in the Heater Shell when
it is drained.
2. Open the Drain Ball Valve in the Bottom Head and allow the potable water in the Heater
Shell to drain completely. If the unit is a Water-to-Water Double-Wall Heater (WWDW-24,
WWDW-45 or WWDW-68), the Drain is located on the Shell and may either be plugged with
a 3/4” NPT Plug or equipped with a Ball Valve and additional drain piping. Remove Plug or
open Drain Ball Valve as applicable.