Trane ESP #'s

[turbo50mike]

I am ordering some 35 and 40 ton Trane Voyager rooftops and the sales rep is asking me to verify the ESP on the units. The 35 he has listed as 2.0in H20, and the 40's at 2.2 in H20.

With no exaggeration, this is the first time I have been asked to 'verify' these numbers.

All three systems will be changeover/bypass VariTrac systems.

My question is, what exactly do I verify? And why would I want to change this rating?

Thanks in advance,
MJB

[controldude]

ru using varitrane vav's or round dampers if it's the round dampers I would get the units set for lower static so not to blow the blades off especially on 12" or larger varitrac dampers also make sure you order properly sized rectangular bypass dampers because at that size of unit you will ruin those dampers if you try to use round.

[turbo50mike]

As of right now we are only doing the rooftops and main trunks - the space is vacant and will be built to suit, so we could use whatever we want.

Since we would typically use the round Trane 'VVT' pressure dependent dampers in the changeover bypass setup, that's what we were planning on. Although we have used the VariTrane pressure independent boxes (with the sampling tubes) before as well on the bypass systems.

And yes, we always use the rectangular bypasses with opposing blades.

Even if this unit has an ESP of 2.0, with a properly sized bypass wouldn't we be in control of the actual static pressure? That's the part I don't get.

We would have the potential for higher pressure, but we don't necessarily have to use it.