Pneuma
07-21-2008, 03:56 PM
Throwing this out to the masses for ideas. This is at my church where I am a trustee.
This is in the DC area.
Sanctuary has four 10 ton lennox units.
Each unit has a single refrigeration circuits feeeding a single 10 ton coil sitting on top of twinned gas furnaces.
So that's 8 furnaces 4 evap coils 4 condeensing units. twinning kits, relays up the wazzoo ect. It's hard to look at really.
The existing condening units have the two speed Bristol compresors but have never been hooked up to operate that way. In fact someone has installed a one stage cooling stat and it's running two of the ten ton units.
Anyway now a compressor is toast in one of the units. Units were originally installed in 1991.
So the way I see it I can
A replace the compressor with a single speed 10 ton.
B replace the condensing unit with an r-22 unit
C replace the condensing unit and coil, flush the lines and get away from the r-22.
As is the case with churches money is tight.
The system is set up so you have 20 tons at opposite ends of the sanctuary.
Trane makes a 10 ton condensing unit with a pair of 5 ton scrolls manifolded so you can use it on a single circuited system. Seems like not a bad way to go.
One other thing, the duct work for each 10 ton evap coil ties together into a common trunk. So you can end up with a wet coil and a dry coil and the air flow problems thatcauses. Except of course where that was solved with the singe stage stat!
Suggestions and opinions all welcome. BTW I have 20 years in HVAC so feel free to ask technical questions or give technical answers.
Thanks!
This is in the DC area.
Sanctuary has four 10 ton lennox units.
Each unit has a single refrigeration circuits feeeding a single 10 ton coil sitting on top of twinned gas furnaces.
So that's 8 furnaces 4 evap coils 4 condeensing units. twinning kits, relays up the wazzoo ect. It's hard to look at really.
The existing condening units have the two speed Bristol compresors but have never been hooked up to operate that way. In fact someone has installed a one stage cooling stat and it's running two of the ten ton units.
Anyway now a compressor is toast in one of the units. Units were originally installed in 1991.
So the way I see it I can
A replace the compressor with a single speed 10 ton.
B replace the condensing unit with an r-22 unit
C replace the condensing unit and coil, flush the lines and get away from the r-22.
As is the case with churches money is tight.
The system is set up so you have 20 tons at opposite ends of the sanctuary.
Trane makes a 10 ton condensing unit with a pair of 5 ton scrolls manifolded so you can use it on a single circuited system. Seems like not a bad way to go.
One other thing, the duct work for each 10 ton evap coil ties together into a common trunk. So you can end up with a wet coil and a dry coil and the air flow problems thatcauses. Except of course where that was solved with the singe stage stat!
Suggestions and opinions all welcome. BTW I have 20 years in HVAC so feel free to ask technical questions or give technical answers.
Thanks!