11
3. Water heater thermostat not turned up high
enough.
4. Water heater thermostat not calibrated properly.
5. Restricted or improperly installed dip tube in water
heater.
6. Restriction somewhere in heating loop. Confirm
that no other check valves or devices have been
installed in the heating loop except as supplied by
First Co.
Note:
Some water heaters come with a normally
closed spring-loaded check valve factory installed
on one of the space heating connections. Since
the circulating pump in the
Aquatherm
®
system
may not be able to open this valve in addition to
the
Aquatherm
®
check valve, this valve should
be removed before installation.
7. Air handler or hot water coil not large enough.
8. Water heater not large enough.
Hot water circulates through hot water coil during
cooling cycle:
1. Check valve may be stuck open allowing "thermo-
syphoning" (circulation) of hot water. This occurs
when the hot water pipes are not capped-off dur-
ing installation, allowing foreign debris such as
solder, insulation, and other building materials to
enter the piping. If not completely purged from the
system, this "debris" can lodge under the check
valve seat and allow hot water to flow through the
hot water coil even in the summer. To solve this
problem, flush the heating loop several times as
indicated in the "start-up procedure" on Page 7.
note: Check valve in models made after year 1999
are located in the pump itself.
CONCLUSION
Always leave the appropriate literature and / or
manual with the homeowner and whenever possible
take the time to explain the operation and advantages
of the system.
All technical specifications subject
to change without notice.
TROUBLESHOOTING
(Most likely problems and cause)
Important:
For system to operate properly
power
should be turned ON and all shut - off valves should
be OPEN.
Pump does not run:
These pumps may sometimes
“stick” due to non - use and fail to start. Before replacing
pump:
1. Turn off power. On Grundfos pumps remove large
screw plug in end of pump motor and turn shaft sev-
eral times with a small screwdriver. Replace plug and
start system. Pump should start.
2. If pump
has
to be replaced, first shut off all isolation
valves between the water heater and air handler
and relieve the city water pressure by opening the
air purge valve. Then remove the four screws that
attach the pump motor to the pump volute rather than
un-soldering the entire pump assembly.
Fan motor runs on cooling but not on heating:
Thermostat is wrong type (a gas furnace type ther-
mostat will not bring on the fan motor in the heating
cycle on certain air handlers). For correct type of
thermostat, see “accessories”.
Note:
FWA-HW air handler has a blower delay.
Pump is noisy:
Air may still be in the heating loop. Re-purge the
system as described under “start - up procedure".
Water heater T & P valve “weeping”:
This situation usually occurs in those systems located
in areas where local codes require the installation of
a “backflow preventer” in the cold water supply line
to the water heater. This situation is caused by the
expansion of the water when heated. An expansion
tank may be required to solve this problem. Contact
local plumbing authorities for assistance.
Insufficient or no heat:
1. Air still in heating loop. Re-purge system.
2. Inlet and oulet piping connections at the air handler
may be piped backwards. (See "Piping connec-
tions").
