Tjernlund HST_HS115_HSUL-J, 1, 2 Series (Discontinued) 8504060 Rev A 11/99 User Manual

Page 17

Solution: Replace the Relay/Timer (HST)
Part # 950-1067 or Ice Cube Relay (HSUL) Part # 950-1040

Solution: Contact the appliance manufac-
turer for further assistance.

Step 3.
Reinstall the WHITE/BROWN wire on Relay/Timer terminal #5 (HST) or the
ORANGE wire from Ice Cube Relay (HSUL).
Verify thermostat is not calling for heat.

Interlocked directly with gas valve
Check for 24V across appliance control such as (Aquastat B1/B2), (Intermittent
Ignition Module MV - MV/PV) or (Standing Pilot TH - Hot & TR - Common).

Interlocked with thermostat at appliance
Check for voltage across W & C at thermostat. If voltage under 24V is present
and the model is a HST with a set-back thermostat, a 24V isolation relay will
have to be installed to isolate the 4 & 5 coil inputs on Relay/Timer. Wiring dia-
gram is included on Page 12 of these instructions.

No call for heat

Contact Tjernlund Products, Inc. for
additional assistance.

24 Volts present

Step 1.
Confirm that thermostat is not
calling for heat.

Step 2.
With the Power Venter running, remove the WHITE/BROWN
wire on Relay/Timer terminal #5 (HST) or the ORANGE wire
from Ice Cube Relay (HSUL).
Result: Power Venter should shut off within 10 minutes
(HST). Power Venter should shut off immediately for HSUL.

Yes

24 Volts not present

Step 1.2
Interlocked directly with gas valve
Check for loose connections between appli-
ance and Power Venter.

Interlocked with thermostat at furnace
Contact T-Stat manufacturer for further
assistance.

24V

24Volts

Not Present

Solution: Contact appliance manufacturer
for further assistance.

Step 1.1
Interlocked directly with gas valve
Verify 24V across appliance control such
as (Aquastat B1/B2), (Intermittent Ignition
Module MV - MV/PV), or (Standing Pilot
TH - Hot & TR - Common) during call for
heat.

Interlocked with thermostat at furnace
Verify 24V across R & C on furnace ter-
minal strip.

Step 2
Remove 115V power source to
the Power Venter. Remove
the two BLACK leads from the
Relay and connect them
together. Reestablish 115V.
Result: Power Venter runs
continuously.

Solution: Replace
Relay/Timer (HST) Part #
950-1067 or Ice Cube Relay
(HSUL) Part # 950-1040

24V

Solution: Replace Power Venter Motor.
Part #’s
HSJ 950-1020
HS1 950-1020
HS2 950-1021

Yes

Step 1
Activate thermostat to call for
heat. Check for 24V across
terminals 4 and 5 of the
Relay/Timer (HST) or the coil
of Ice Cube Relay with the
BLUE and ORANGE leads
attached (HSUL).

SYMPTOM 1:

POWER VENTER DOES NOT RUN DURING CALL FOR HEAT (HSUL & HST SERIES ON GAS OR HST
SERIES ON OIL WIRED WITH SINGLE ZONE 24V THERMOSTAT)

SYMPTOM 2:

POWER VENTER RUNS CONTINUOUSLY / ERRATICALLY (HSUL & HST SERIES
ON GAS OR HST SERIES ON OIL WIRED WITH SINGLE ZONE 24V THERMOSTAT)