Applications; Re-Circulation - Takagi 710 Installation Manual And Owner's Manual

APPLICATIONS


In order to purge air in water pipes within a closed-loop system, an air vent and
air separator should be installed in to the system. Required circulation flow rates
are labeled next to each application diagram. These flow rate requirements must
be followed.

Toxic chemicals used in boiler treatments such as alcohol, glycerol and glycol groups
must not be introduced into the system if the system incorporates an open-loop potable
water system.

Toxic chemicals used in boiler treatments such as alcohol, glycerol and glycol group
must not be introduced into the system when used for open loop potable water and
space heating.

The water heater can be used to supply potable water and space heating and shall not
be connected to any heating system or component(s) previously used with non-potable
water where any chemicals were added to the water heating appliances.

When the system requires water for space heating at temperatures higher than required
for other uses, a means such as a mixing valve shall be installed to temper the water for
those other uses in order to reduce scald hazard potential.
 Water temperature over 125 F (52ºC) can cause severe burns instantly or death from
scalds.

Chemicals such as diluted Glycol can be used for radiant floor, Hydro/fan coil air or
Baseboard heating only. The diluted solution of glycol must contain between 25 and
55% of Glycol. Be aware that in closed-loop glycol systems, low pressure in the heat
exchanger can cause low-temperature boiling, resulting in excessive noise and damage
to the water heater. Consult with the glycol maker for specifications prior to use.
* The recirculation pump is to be controlled by:
‐Dual‐set aquastat (recommended w/timer)
OR
‐"Pump Control Connections". Refer to p.21.
* The recirculation pump is to provide no less
than 2 GPM and no more than 4 GPM through
each activated unit in the system.
Space Heating Applications
Hot water outlet to
fixtures
Recirculation
Air
pump
separator
This is a concept drawing only.
WARNING

Re-circulation:

Air Vent
S
Check valve
- 41 -
Hot Cold
Water Gas
Water
Inlet
Outlet Inlet
Unions
Ball valves
Gas supply
Expansion tank
Check valve
Y‐Strainer
Cold water
inlet