Heat Reclaim

[etheric999]

Hello all, i ran into a mcquay rooftop unit today,it has something called heat reclaim valve on it could you explain what is heat reclaim for and how does the valve work, thanks.

[emcoasthvacr]

I'll take a stab at this, and I can always be corrected.

It's a valve that you can manually adjust in the return system to mix with the supply system in the chiller -- i'm thinking that this is an older chiller or you would have controllers to adjust the reheat in the return system.

Chiller might be pissed, but hopefully someone can correct me if i'm wrong:D


Hello all, i ran into a mcquay rooftop unit today,it has something called heat reclaim valve on it could you explain what is heat reclaim for and how does the valve work, thanks.

[hvaccolo]

Sounds like a grocery store hvac unit. Heat reclaim uses the heat typically lost to the outdoor air through the refrigeration rack condensing units. The hot gas refrigerant from the rack compressors is diverted (upon a call for heat) to the heat reclaim coils to heat the supply air.

[Andy Schoen]

This should help you out: http://www.sporlan.com/30-20.pdf

[The Doctor]

could this be similar to the humiditrol feature in some Lennox RTUs? It is a coil fed by the discharge line, presumably to reheat the S/A, preventing overcooling.

not too sure on the McQuay, but since you mentioned rooftop, I thought I'd take a stab.
Let's see if that pans out before we discuss what would be the input/s for controlling this reclaim valve

[heatingman]

could this be similar to the humiditrol feature in some Lennox RTUs? It is a coil fed by the discharge line, presumably to reheat the S/A, preventing overcooling.

not too sure on the McQuay, but since you mentioned rooftop, I thought I'd take a stab.
Let's see if that pans out before we discuss what would be the input/s for controlling this reclaim valve

Same principle, its basically free heat, since it's the unwanted heat from somewhere else. On a rtu, it can be two things, one refrigerant reheat self contained within the unit to feed a coil to reheat the air during demidify mode like in the Doctors lennox. Or it can be fed to the unit for the purpose of heating from a refrigeration system, that is rejecting heat anyway. Or, and I have not seen this, but it is possible to use a remote condensor from the rtu to reclaim the heat to a water heater or something, but that would not be found on smaller equiptment.

Also was this valve a automatic valve, or a manual valve?