Friedrich VERT-I-PAK VHA-18K75RTP, Service & Parts Manual, Page: 50 / 103

50 PB
COMPONENTS TESTING
Heating Element and Limit Switch
WARNING
ELECTRIC SHOCK HAZARD
Turn off electric power before service or
installation. Extreme care must be used, if it
becomes necessary to work on equipment with
power applied.
Failure to do so could result in serious injury or
death.
Heating Element
Example
All heat pumps and electric heat models are equipped with a heating element and a limit switch (bimetal thermostat). The limit
switches are in series with the element and will interrupt the power at a designed temperature.
Should the blower motor fail, filter become clogged or air-flow be restricted etc., the high limit switch will open and interrupt
the power to the heater before reaching an un-safe temperature condition.
Heater Elements And Limit Switches’ Specifications
VPAK 9K, 12K and 18K BTUs Models:
2.5 KW, 230 V
, Resistance 18.61 Ohms + - 5%.
Has 1 Limit Switch, Opens at 120° F, Closes at 90° F,
It has a One Time Open Temp. of 145° F.
3.4 KW, 230 V, Resistance 13.68 Ohms + - 5%.
Has 1 Limit Switch, Opens at 120° F, Closes at 90° F,
It has a One Time Open Temp. of 145° F.
5 KW, 230 V, Resistance 9.31 Ohms + - 5%.
Has 1 Limit Switch, Opens at 130° F, Closes at 100° F, It has a One Time Open Temp. of 155° F.
VPAK 24K BTUs Models:
2.5 KW, 265 V, Resistance 24.86 Ohms + - 5%.
Has 2 Limit Switches, Primary Opens at 120° F,
Closes at 90° F, Secondary’s Open Temp. is 145° F.
3.4 KW, 265 V,
Resistance 13.68 Ohms + - 5%.
Has 2 Limit Switches, Primary Opens at 120° F,
Closes at 90° F, Secondary’s Open Temp. is 145° F.
5 KW, 265 V,
Resistance 9.31 Ohms + - 5%.
Has 2 Limit Switches, Primary Opens at 130° F,
Closes at 100° F, Secondary’s Open Temp. is 155° F.
7.5 KW, 265 V (composed of 2, 3.7 KW Elements) Each Has a Resistance of 16.47 Ohms + - 5%.
Each Has 2 Limit Switches, Primary Opens at 155° F, Closes at 125° F With a 1 time Open Temp. of 200° F. Secondary Limit’s
Open Temp. is 200° F.
Figure 708 (Heating Element)