Bryant 450D - Manual (Page 10)

VIII. BALANCE THE SYSTEM
After the unit is in operation and the input has been
measured and adjusted to agree with the rating plate
requirements, balance the system.
Any approved method of checking the air flow over the
water coil may be utilized. Reference is made to the
Bryant Service Manual on Gas Air Conditioners for a
review of standard methods.
IX. PURGE NON-CONDENSIBLES
Purging is accomplished through Valve “A” as shown
in Figure 6, and at Valve “D” at the purge pot.
Operate unit for a minimum of 15 minutes. While still
operating, proceed as follows:
1. Open Valve "D” at purge pot about 1/8 turn. Solu­
tion trapped in valve body will appear as soon as valve
opens. If non-condensibles are present they will follow
this surge of solution. When solution re-appears in
quantity the non-condensibles trapped in the purge pot
will have been released. Close Valve “D”.
2. Attach purge line to Valve “A” as shown in Figure 6
and place free end of purge line in bucket of water.
3. Open Valve “A” about 1/8 to 1/4 turn. If non­
condensibles are present, bubbles will rise to the
surface of the water in the bucket.
4. Leave Valve “A” open until the bubbles cease and
ammonia starts to escape through the purge line.
Presence of ammonia will be clearly indicated by a
sharp, crackling sound (the sound of absorption). Close
Valve “A”.
The installation should now be complete.
HARD FITTII^G-MAX.2,
ADAPTER
PLASTIC PIPE
ADAPTER
HARD FITTING-MAX.2;
HARD NIPPLE MAX. LENGTH 4"
PLAN VIEW
Figure 7
Figure 6
FREEZING WEATHER PROTECTION
1. GAS AIR CONDITIONER
The Gas Air Conditioner has built-in freeze protec­
tion sufficient to protect the chiller and pump plus a
small amount of external hard (non-plastic) pipe as
shown in Figure 7.
2. CHILLED WATER PIPES
If hard pipe is used (instead of plastic) for the chil­
led water lines, be sure that adequate steps are taken
to prevent these pipes from bursting when they are
subjected to freezing temperatures.
Consult Bryant Distributor.
3. BRYANT COIL
If the Bryant coil used with the absorption unit is
subject to freezing it must be protected. Consult
Bryant distributor for recommended procedure to
follow.
4. OPERATION AT FREEZING TEMPERATURES
If the air conditioning system is required to operate
under freezing conditions, consult your Bryant Dis­
tributor for special procedures to follow.
EH 450 - 8-