Unit; System Checkout; Unit Start-Up; Initial Start-Up - Bosch SM024 Installation, Operation And Maintenance Manual

SM AH Series Heat Pump
• Cut crimped ends off the air handler suction
and liquid lines. Connect and braze lines to the
air handler.
The air handler is factory supplied with a holding
charge of dry nitrogen.
• Connect and braze lines to service valves on
the condensing section.
WARNING: Always wrap the body of the
service valve with a wet towel or apply some
other form of heatsink prior to brazing and
direct flame away from the valve body.
Failure to do so will result in damage to the
valve. Valve body temperature must remain
below 250°F to protect the internal rubber "O"
rings and seals.
Figure 16: Valve Sizing Chart
Line
Unit Size
Type
SM024/036 Suction
SM048/060/070 Suction
All Valves Liquid
Pressurize the refrigerant line set and air handler
to 150lbs with dry nitrogen through the ports
provided on the self service valves. Check line set
and unit connections for leaks.
Once system integrity is verified, evacuate line set
and air handler with a good vacuum pump to 500
microns and hold for half hour.
Pump down must never be used with heat
pumps.

SYSTEM CHECKOUT

After completing the installation, and before
energizing the unit, the following system checks
should be made:
• Verify that the supply voltage to the heat pump
is in accordance with the nameplate ratings.
• Make sure that all electrical connections are
tight and secure.
• Check the electrical fusing and wiring for the
correct size.
Valve Allen
Conn. Wrench
Size size
3/4 5/16
7/8 5/16
3/8 3/16
• Verify that the low voltage wiring between the
thermostat and the unit is correct.
• Verify that the water piping is complete and
correct.
• Check that the water flow is correct, and
adjust if necessary.
• Check the blower for free rotation, and that it
is secured to the shaft.
• Verify that vibration isolation has been
provided.
• Unit is serviceable. Be certain that all access
panels are secured in place.

UNIT START-UP

1. Set the thermostat to the highest setting.
2. Set the thermostat system switch to "COOL",
and the fan switch to the "AUTO" position. The
reversing valve solenoid should energize. The
compressor and fan should not run.
3. Reduce the thermostat setting approximately 5
degrees below the room temperature.
4. Verify the heat pump is operating in the cooling
mode.
5. Turn the thermostat system switch to the
"OFF" position. The unit should stop running
and the reversing valve should deenergize.
6. Leave the unit off for approximately (5)
minutes to allow for system equalization.
7. Turn the thermostat to the lowest setting.Set
the thermostat switch to "HEAT".
8. Increase the thermostat setting approximately
5 degrees above the room temperature.
9. Verify the heat pump is operating in the heating
mode.
10. Set the thermostat to maintain the desired
space temperature.
11. Check for vibrations, leaks, etc...

INITIAL START-UP

1. Make sure all valves in heat recovery water
piping system are open. NEVER OPERATE HR
PUMP DRY.
2. Turn on the heat pump. The HR pump should
not run if the compressor is not running.
3. turn the HR switch to the "ON" position. The
pump wil operate if entering water
temperature to HR is below 120° F.
4. The temperature difference between the water
entering and leaving the heat recovery should
be 5° to 15° F.
SYSTEM CHECKOUT | 13
8733920846 (2015/01)