Draining Outer (Boiler Water) Tank; Draining Inner (Domestic Water) Tank - TriangleTube PRESTIGE Excellence 110 Installation & Maintenance Manual

CHAPTER 4 - WATER HEATER MAINTENANCE
If antifreeze is used in boiler water, check concentra-
tion. Boiler water (including additives) must be prac-
tically non-toxic, having toxicity rating or class of 1, as
listed in Clinical Toxicology of Commercial Products. A
maximum 50/50 mixture of inhibited propylene glycol
is recommended. Follow antifreeze manufacturer's in-
struction.
WARNING
• Do not use automotive, ethylene glycol
or petroleum-based antifreeze. Do not
use any undiluted antifreeze. This can
cause substantial property damage, seri-
ous injury, or death.
• Water from opened drain valves, unions
and other connections may be extremely
hot. To avoid substantial property dam-
age, serious injury, or death:
Ū Tighten all drain hose connections.
Ū Direct hot water away from all per-
sons.
14
4.4.

Draining Outer (Boiler Water) Tank

1. Disconnect power supply to water heater.
2. Close boiler isolation valves.
3. Connect hose to boiler water drain valve under wa-
ter heater. Open and drain water to a safe place.
4. To speed draining procedure, loosen air vent on top
of tank.
5. When draining is complete, close drain valve and
retighten air vent.
4.5.

Draining Inner (Domestic Water) Tank

See Fig. 4 on page 7.
1. Disconnect power supply to water heater.
• If outer (boiler water) tank pressure is greater
than 15 psig, close boiler isolation valves and
relieve pressure before proceeding.
2. Close domestic cold water inlet isolation valve.
3. Connect a hose to domestic water drain valve at
cold water inlet. Hose should extend to drain at
floor level to allow siphoning of domestic water
tank.
4. Open hot water faucet at highest point above heater.
5. Open domestic water drain valve to start siphoning.
6. When draining is complete, close hot water faucet
and domestic water drain valve.