System Operation; Power Venter Sizing - Field Controls PVE-100 Instructions Manual

CONTROL KITS
The following are the most commonly used Control Kits.
CK-20F: For operation with 30 millivolt or 750 millivolt gas-fi red water heaters, gas-fi red space heaters
and gas-fi red pool or spa heaters with an internally mounted thermostat. Includes a non-adjust-
able post purge timer. Use the CK-22 for an adjustable post purge timer.
CK-21: For operation with gas-fi red instantaneous water heaters with a pressure tap port in the burner
manifold.
CK-41: For operation with gas-fi red furnaces, boilers, unit heaters and water heaters operating with a
24 VAC gas valve.
CK-43: For operation with draft induced gas-fi red furnaces, boilers, unit heaters and water heaters
operating with a 24 VAC gas valve. Includes an adjustable post purge relay/timer, and a draft
control for draft induced appliances. Use the CK-43F for a non-adjustable post purge relay/
timer. Use the CK-44F for draft hooded appliances.
CK-61: For operation with all 120 VAC oil-fi red systems. Has electronic post purge. Use the CK-62 for
a thermally activated post purge.
CK-81: For operation with 750 millivolt operated boilers, furnaces, water heaters, pool or spa heaters
and gas-fi red fi replaces when operating with a remote mounted 24 VAC thermostat. For
operation with a 120 VAC thermostat or wall switch, use the CK-80.
CK-91: For operation with a draft induced gas-fi red furnace or boiler and a 30 millivolt operated
water heater. Includes an adjustable post purge relay/timer and a draft control. Use the CK-92
for draft hooded appliances. Use the CK-91F or 92F for a non-adjustable post purge relay/
timer.

SYSTEM OPERATION

1. The thermostat (wall thermostat, or aquastat) calls for heat and energizes a relay which activates the
power venter. After the venter motor has come up to speed, the pressure switch closes. This completes the
circuit to the burner and allows the burner to fi re.
2. For millivolt controlled water heaters, the gas pressure switch on the gas valve activates the power venter
at the same time as the burner fi res.
3. After the heating requirement has been satisfi ed, the thermostat circuit will open and deactivate the
burner and power venter circuit.
4. For venting systems equipped with a post purge device, the power venter operates for a period of time
after the burner has shut off to purge remaining fl ue gases.

POWER VENTER SIZING

In order to choose the correct size power venter for a particular installation, the total input fi ring rate and
total equivalent length of vent pipe to be used must be known. Refer to the following sizing chart to determine
the maximum allowable equivalent feet of pipe for each model used with the pipe diameters shown. When
venting multiple appliances, add the input of each appliance to determine the total input. Always choose a
power venter that is capable of handling more than the system requires. The choke plate can be adjusted to
compensate for the diff erence.
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