Minimum pressure to a txv

[Grizzly]

Hi Marc.
Some of the sites I look after have tier chillers running all year round despite the ambient being well below their design parameters.
Extreme I know but as they say "That's Life"!
I would be interested to know which Airedale that was as they have 2 different selectable control strategies.
Add this to their free cooling units and it can get interesting.
No disrespect to Airedale, theirs is some good kit, Only even theirs don't like all ambient conditions.

Grizzly

[marc5180]

Hi Marc.
Some of the sites I look after have tier chillers running all year round despite the ambient being well below their design parameters.
Extreme I know but as they say "That's Life"!
I would be interested to know which Airedale that was as they have 2 different selectable control strategies.
Add this to their free cooling units and it can get interesting.
No disrespect to Airedale, theirs is some good kit, Only even theirs don't like all ambient conditions.

Grizzly

Hi Grizzly,
Tier units? I'm not familiar with those, I take it they are heat pump chillers?

I think the Airedale units were CUHS 6.0, the ones where the fan discharges the air upwards.

I noticed when it was in heat mode and the outdoor fan speed controller was in auto that it the fan as
The fan speed increased suction pressure increased but also discharge pressure increased and the
Opposite if the fan slowed down.
I would have expected the fan to run flat out in order to evaporate all the refrigerant in the coil but
It didn't- it looked like it was maintaining head pressure.