Whirlpool EDP/EDN - Manual (Page 10)

Page 10 LAARS HEATING SYSTEMS
WARNING
Failure to install a hot water tempering (mixing)
valve (12) creates a scalding hazard with potential for
serious bodily injury. Some brands of tempering
(mixing) valves are not designed as anti-scald valves.
Where domestic water is supplying multiple
apartments or large whirlpool tubs, additional storage
tank may be connected as shown in Figure 13. The
bronze circulator shown must be connected to tank
aquastat and must not run continuously. If the
circulator is wired to run continuously, unit's domestic
water flow switch will keep the unit in domestic water
priority, and no water will be allowed to be sent to the
heating system.
SECTION 4.
Hydronic Heat Piping
4A. Hydronic Piping
The appliance incorporates its own circulating
pump and bypass loop and is capable of providing
flow through heating zones, in addition to what it
needs for itself. Model size 110 is capable of
providing flow for two heating zones (up to 67 feet of
¾" baseboard each), and model 175 is capable of
providing flow for four heating zones (up to 67 feet of
¾" baseboard, each).
EDP/EDN boilers installed in radiant (in floor)
systems and other low mass boilers should be provided
with a buffer/blender tank to assure a controlled
supply temperature, and to prevent short cycling. In
radiant systems utilizing 3-way tempering valves, a
bypass pipe must be installed between supply and
return piping.
1.
EBP ONLY: Connect system supply to 1¼"
supply connection marked “SUPPLY”.
2. EDP/EDN ONLY: Connect 1¼" thermostatic
union to system supply connection in direction
designated with union.
3. Pipe the discharge of the relief valve, full size, to
a drain or in a manner to prevent injury in the
event of pressure relief.
4. Install an air purger in flow supply line as shown
in Figures 15, 16 or 17.
5. Install automatic float type air vent on air scoops.
6. Install a diaphragm expansion tank in boiler
outlet piping. To ensure sufficient expansion
volume for the hydronic system water, due to
heat-up and cool-down during normal operation,
a #30 or larger expansion tank must be used on
EBP combo units.
NOTE: Never install expansion tank and auto
fill valve on return.
7. If necessary, install a properly sized circulator
with optional isolation valves in supply beyond
expansion tank.
Caution
All hot water pipes must be installed with a minimum
1" (25mm) clearance from combustible materials.
8. Connect boiler feed water supply with shut off
valve to inlet connection of automatic fill valve.
Locate in boiler outlet piping.
9. If codes require, install suitable back flow
preventer between automatic fill valve and city
main.
10. The appliance may be installed in single and
multiple zone systems (using either zone valves
Figure 14. EBP Domestic Water Piping with Recirculating Loop.