Smart 40 Indirect Water Heater Manual

661A0300 - Rev B
24
Do not use automotive, ethylene glycol or
petroleum-based antifreeze. Do not use
any undiluted antifreeze. This can cause
severe personal injury, death or substantial
property damage.
Water from opened drain valves, unions
and other connections may be extremely
hot. To avoid severe personal injury, death
or substantial property damage:
- Tighten all drain hose connections.
- Direct hot water away from all persons.
Draining Inner (Domestic Water) Tank
There are 3 methods typically used in the
draining of the inner tank. The first method
outlined as Option 1 is to siphon the water
out. This method is typically the easiest to
perform, but may be lengthly in time to com-
plete. The second method, shown as Option 2,
uses compressed air. This method is more
complicated however it is generally quicker
in draining the tank. The final method,
Option 3, use a pump to drain the tank. As
with Option 2, Option 3 is generally more
complicated, but is quicker in draining the
tank.
Prior to draining the inner tank, ensure the
following is completed:
1. The snap-set wiring connection at the
water heater is disconnected.
2. The DHW system supply isolation valve
is closed.
3. The outer (boiler water) tank pressure is
less than 15 psig.
Reference domestic piping diagrams Figs. 1,
2 and 3 on page 8 and 9.
Draining Inner Tank - Option 1
1. Connect a hose to the domestic water drain
valve at the cold water inlet. The hose should
extend to a drain at floor level to allow siphon-
ing of the domestic inner tank.
2. Open a hot water faucet at the highest point
above the water heater.
3. Open the domestic water drain valve to start
the siphoning of the domestic inner tank.
4. When draining is complete, close the hot
water faucet and the domestic drain valve.
Draining Inner Tank - Option 2
1. Connect a hose to the domestic water drain
valve at the cold water inlet. Direct the hose to
a proper drain/suitable place for drainage.
2. Close the isolation valve on the DHW system
hot outlet of the water heater.
3. On the hot water outlet piping between the
water heater and the isolation valve install a
shrader (air tank) valve or some other fitting or
means that allows connection of an air hose
from a compressor.
4. Open the domestic water drain valve on the
cold water inlet.
WARNING
BEST PRACTICE
NOTICE
WARNING
Water Heater Maintenance
Smart manual_Smart manual 10/29/14 10:00 AM Page 26