Retrofit assembly for operating a motor of an hvac system as a multi-stage motor and an hvac system including the retrofit assembly

Patent metadata

Field	Value
Publication number	US-2016348939-A1
Application number	US-201514724477-A
Country	US
Kind code	A1
Filing date	May 28, 2015
Priority date	May 28, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

Retrofit assemblies and an HVAC unit including a retrofit assembly are disclosed herein. In one embodiment, the retrofit assembly includes: (1) a base plate, that is mountable to a face of a motor speed driver (MSD), having an attachment area, (2) a standoff bracket that is mountable to the attachment area of the base plate and having a configuration that secures the MSD in a position relative to an interior wall of the HVAC system and provides clearance between the interior wall of the HVAC system and the MSD such that wires can be routed between the MSD and the interior wall and (3) a control interface, electrically connectable between the MSD and a thermostat of the HVAC system, configured to differentiate thermostat calls from the thermostat and translate the thermostat calls to coordinate blower speeds for the blower motor via the MSD.

First claim

What is claimed is:

1 . A retrofit assembly for a constant air volume heating, ventilation, and air conditioning (HVAC) system, comprising:
a base plate, that is mountable to a face of a motor speed driver (MSD), having an attachment area; a standoff bracket that is mountable to said attachment area of said base plate and having a configuration that secures said MSD in a position relative to an interior wall of said HVAC system and provides clearance between said interior wall of said HVAC system and said MSD such that wires can be routed between said MSD and said interior wall of said HVAC system; and a control interface, electrically connectable between said MSD and a thermostat of said HVAC system, configured to differentiate thermostat calls from said thermostat and translate said thermostat calls to coordinate blower speeds for said blower motor via said MSD.

2 . The retrofit assembly of claim 1 , wherein said standoff bracket is a right-angled metal strip that is attachable to said attachment area of said base plate.

3 . The retrofit assembly of claim 1 , wherein said standoff bracket has a mounting face and one or more standoff supports that extend from said standoff bracket at least by ninety degrees and have a length sufficient to create a space between said standoff bracket and said interior wall of said HVAC system when mounted thereto.

4 . The retrofit assembly of claim 1 , wherein said standoff supports are individual leg members.

5 . The retrofit assembly of claim 1 , further including an electrical relay mounting plate that is mountable to said base plate.

6 . The retrofit assembly of claim 5 , wherein said control interface includes a relay block and said relay block is mountable to said electrical relay mounting plate.

7 . The retrofit assembly of claim 6 , wherein said relay block includes four relays including a heat speed relay, a blower cooling speed relay and a continuous low speed relay.

8 . The retrofit assembly of claim 6 , wherein said relay block includes only four relays.

9 . The retrofit assembly of claim 6 , wherein said control interface includes a relay coil harness configured to provide said thermostat calls to operating coils of relays of said relay block and a relay contactor harness configured to provide motor control signals from contacts of said relays to said MSD.

10 . The retrofit assembly of claim 1 , further comprising a power supply conversion circuit that includes said MSD and a blower motor contactor employed as a distribution block.

11 . A heating, ventilation and air conditioning (HVAC) unit, comprising:
a controller configured to direct operation of said HVAC unit to condition air for an enclosed space employing constant air volume; and a retrofit assembly configured to convert said HVAC unit to a Multi-Stage Air Volume HVAC unit, said retrofit assembly comprising a control interface configured to receive thermostat calls for operating said HVAC unit at said constant air volume and translate said thermostat calls to motor control signals to operate said HVAC unit as said Multi-Stage Air Volume HVAC unit.

12 . The HVAC unit as recited in claim 11 , wherein said retrofit assembly further includes a power supply converter circuit having a motor speed driver (MSD) that receives said motor control signals and operates a blower motor of said HVAC unit at multiple speeds.

13 . The HVAC unit as recited in claim 12 , wherein said power supply converter circuit further includes a blower contactor of said HVAC unit that is used as a distribution block to deliver line power to said MSD and receive output power from said MSD to provide to said blower motor.

14 . The HVAC unit as recited claim 12 , wherein said control interface includes a relay block, a relay coil harness configured to provide said thermostat calls to operating coils of relays of said relay block and a relay contactor harness configured to provide said motor control signals from contacts of said relays to said MSD.

15 . The HVAC unit as recited in claim 12 , further comprising:
a base plate that is mountable to a face of said MSD and having a dimension that is larger than a dimension of said MSD to provide an attachment area; and a standoff bracket that is mountable to said attachment area of said base plate and having a configuration that secures said MSD in a position relative to an interior wall of said HVAC unit and provides clearance between said interior wall of said HVAC unit and said MSD such that wires can be routed between said MSD and said interior wall of said HVAC unit.

16 . The HVAC unit as recited in claim 15 , wherein said standoff bracket has a mounting face and one or more standoff supports that extend from said standoff bracket at least by ninety degrees and have a length sufficient to create a space between said standoff bracket and said interior wall of said HVAC unit when mounted thereto.

17 . A retrofit assembly for converting a single speed motor of a heating, ventilation and air conditioning (HVAC) unit to operate as a multi-speed motor, said retrofit assembly comprising:
a power supply conversion circuit including a motor speed driver (MSD) and configured to provide power to a motor of said HVAC unit via said MSD and a contactor for said motor; a control interface configured to translate control signals for operating said motor at a single speed to motor control signals for operating said motor at multiple speeds, and provide said motor control signals to said MSD; a base plate that is mountable to a face of said MSD and having a dimension that is larger than a dimension of said MSD to provide an attachment area; and a standoff bracket that is mountable to said attachment area of said base plate and having a configuration that secures said MSD in a position relative to an interior wall of said HVAC unit and provides clearance between said interior wall of said HVAC unit and said MSD such that wires can be routed between said MSD and said interior wall.

18 . The retrofit assembly as recited in claim 17 wherein said motor is a blower motor for said HVAC unit.

19 . The retrofit assembly as recited in claim 17 further including an electrical relay mounting plate that is mountable to said base plate, wherein said control interface includes a relay block mountable to said electrical relay mounting plate, said relay block configured to receive said control signals and, based thereon, provide said motor control signals to said MSD.

20 . The retrofit assembly as recited in claim 17 wherein said power supply conversion circuit employs said contactor as a distribution block.

Assignees

• Lennox Ind Inc

Inventors

• Davis Ii Walter
• Perez Eric M
• Chanthalangsy Eric

Classifications

• F24F13/00 Primary

  Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening · CPC title

• F24F2013/207

  with control knobs; Mounting controlling members or control units therein · CPC title

• F24F11/77 Primary

  by controlling the speed of ventilators · CPC title

• Y02B30/70

  Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating · CPC title

• F24F11/46

  Improving electric energy efficiency or saving · CPC title