46
AGZ 010B through 034B
IOMM AGZB1
ALSO
If Unit Mode = Cool,
AND
At least one compressor is running,
AND
LWT error > Upper Control Band,
AND
Pulldown rate <= Max pulldown rate,
AND
Compressors running < unit capacity limit,
AND
Stage up timer is expired,
THEN
Stage Up Now
= True
ALSO
If Unit Mode = Ice,
AND
no compressors are running,
AND
LWT error > Start delta + Upper Control Band,
AND
Motor Protect Timer is expired,
AND
Ice Delay Timer is expired,
AND
Stage up timer is expired,
THEN
Stage Up Now
= True
ALSO
If Unit Mode = Ice,
AND
LWT error > 0,
AND
At least one compressor running,
THEN
Stage Up Now
= True
Stage Down Now
The
Stage Down Now
flag is set based on the following tests:
If Unit Mode = Cool,
AND
LWT error < -(Lower Control band),
AND
More than one compressor is running,
AND
Stage down timer is expired,
THEN
Stage Down Now
= True
ALSO
If Unit Mode = Cool,
AND
LWT error < -(Lower Control band) - stop delta,
AND
One compressor is running,
AND
Stage down timer is expired
THEN
Stage Down Now
= True
ALSO
If Unit Mode = Cool,
AND
Number of compressors running > Demand limit,
AND
Stage down timer expired,
THEN
Stage Down Now
= True
ALSO
If Unit Mode = Ice,
AND
LWT error < 0,
THEN
Stage Down Now
= True
Compressor Sequencing
Compressor staging is based primarily on compressor run-hours and starts. Compressors
that have less starts will normally start before those with more starts. Compressors that
have more run-hours will normally shut off before those with less run-hours.
Summary of Contents for AGZ 010BM
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