New system tripping on low pressure??

[DTLarca]

But this being a kitchen, we need to offset a heavy moisture load from cooking, washing dishes, etc... so let's lower our target RH to say 40%.

Following the same procedure on the psych chart, our new supply air wetbulb would be about 11C.

Choosing 40% is very arbitrary - why not 45% or 35% or even 30%.

I have attached a psychrometric chart showing two different SHR's being achieved with two different BPF's but each with 11°C WB leaving temps.

[Gary]

Choosing 40% is very arbitrary - why not 45% or 35% or even 30%.

The 40% is arbitrary. I have no idea what RH% will be needed to offset the unknown moisture load. Actually, I chose 40% because it is the bottom of the comfort range (40-60%RH).

I have attached a psychrometric chart showing two different SHR's being achieved with two different BPF's but each with 11°C WB leaving temps.

I don't see where they both have a leaving wetbulb of 11C?

[DTLarca]

I don't see where they both have a leaving wetbulb of 11C?

You sure?

[Gary]

You sure?

Am I sure I don't see it? Yes.

Am I sure you are wrong? No.

[DTLarca]

Am I sure I don't see it? Yes.

Am I sure you are wrong? No.

Healthy scepticism

See the attached, Gary.

[Gary]

Healthy scepticism

See the attached, Gary.

Maybe after a few more cups of coffee it will sink in.

In any case, would you agree that a volume of air at 11C WB when warmed to 25C DB will be at ~40% RH?

[DTLarca]

Maybe after a few more cups of coffee it will sink in.

In any case, would you agree that a volume of air at 11C WB when warmed to 25C DB will be at ~40% RH?

No

I could give you a final RH, after a 100% sensible reheat to 25°C, anywhere from 42% to 23% using ADP's from 11°C to 2°C using different BPF's.