Manual

ManualsBrandsKees ManualsHoodsDFG (DIRECT FIRED GAS) MAKE-UP AIR UNITS

KEES, INC.

Installation & Maintenance Manual

DFG Series Direct Gas Fired

Make-up Air Heaters

Table of Contents

Page # Topic

1 Description of Operation

1 Receiving the Unit

1 Positioning the Unit

1 Curbing the Unit

2 Piping the Unit

2 Wiring the Unit

3 Optional Equipment

5 Controls Description

9 Troubleshooting Guide

13 Start-up of the Unit

15 Maintenance Schedule

FOR YOUR SAFETY

If you smell gas:

1. Open windows.

2. Don't touch electrical switches.

3. Extinguish any open flame.

4. Immediately call your gas supplier.

FOR YOUR SAFETY

The use and storage of gasoline or other

flammable vapors and liquids in open

containers in the vicinity of this appliance is

hazardous.

WARNING: Improper installation, adjustment,

alteration, service or maintenance can cause

property damage, injury or death. Read the

installation, operating and maintenance

instructions thoroughly before installing or

servicing this equipment.

Summary of content (16 pages)

PAGE 1
KEES, INC. Installation & Maintenance Manual DFG Series Direct Gas Fired Make-up Air Heaters Table of Contents Page # 1 1 1 1 2 2 3 5 9 13 15 Topic Description of Operation Receiving the Unit Positioning the Unit Curbing the Unit Piping the Unit Wiring the Unit Optional Equipment Controls Description Troubleshooting Guide Start-up of the Unit Maintenance Schedule FOR YOUR SAFETY If you smell gas: 1. 2. 3. 4. Open windows. Don't touch electrical switches. Extinguish any open flame.
PAGE 2
INSTALLATION INSTRUCTIONS Description of Operation The KEES DFG series heater is a direct gas fired heater using 100% outside air. It is designed for outdoor installation but may be mounted indoors provided the intake is ducted to the outdoors. Natural gas or propane fuel the burner. The flame is modulated to provide a constant preset discharge temperature or room temperature (optional).
PAGE 3
Piping the Unit Applicable codes and standards must be followed in sizing and installing the gas piping. A manual gas shutoff valve is provided for field installation. A 1/8" N.P.T. plugged tapping must be installed immediately upstream of this valve for pressure test gauge connection. The pressure at this tap must fall within the minimum and maximum pressures shown on the nameplate in order for the unit to operate properly. 1/2" or greater diameter pipe is recommended for the incoming pipe.
PAGE 4
OPTIONAL EQUIPMENT LOW TEMPERATURE LIMIT SWITCH This control is commonly called a Freeze Stat. This unit mounted, low limit thermostat will shut the blower off if the discharge temperature drops below 40°F. A Bypass Timer which is part of the control will allow the unit to run on a cold start-up. After 5 minutes, control power will pass through the low temperature thermostat. If the remote panel has operating lights, the red light will glow on "ALARM".
PAGE 5
CONTROL SYSTEM DIAGNOSTIC INDICATOR This component is used as a diagnostic tool for troubleshooting burner problems. It attaches to the burner control module monitoring the function of the module and storing in memory any failures that occur. AUDIBLE ALARM An alarm horn is supplied with the remote control panel. On a flame failure, the horn will sound. A reset of the flame failure relay will silence the horn.
PAGE 6
HIGH PRESSURE REGULATOR It is necessary to install a high-pressure regulator upstream of the unit if the incoming gas pressure is greater than ½ PSIG. This item ships loose for field installation and is available in 1” and 1-1/4” diameter pipe sizes. HIGH AND/OR LOW GAS PRESSURE SWITCH As an option these switches are available to monitor high, low or high & low gas pressure to the burner. If improper gas pressure is measured than the burner circuit is de-energized.
PAGE 7
2. DAMPER MOTOR The function of the damper motor is to power open or spring return close the dampers on the discharge or intake of the unit. It will seal off or open the building to the make-up air supply. Test: 3. Remove damper motor linkage cover. Energize unit. Damper motor will open, pushing linkage to open the damper blades. De-energize unit. Damper motor will close damper blades by spring return.
PAGE 8
7. LOW GAS PRESSURE SWITCH The function of this switch is to de-energize the burner circuit if the gas pressure to the burner is below its setting. Manual reset to energize. Set: 2" W.C. Test: Using test gauge in parallel with sensing tubing, adjust unit to high fire, decrease regulator pressure at gauge below 2" W.C. 8. BURNER CONTROL MODULE This module supervises the flame circuit and the energizing of the ignition/pilot and main gas valves.
PAGE 9
13. REMOTE TEMPERATURE SELECTOR The function of this dial is to set the desired discharge temperature the unit is to supply. This dial working in conjunction with the discharge temperature sensor sends a D.C. voltage signal to the amplifier that modulates the burner to a specific supply temperature. 14. ROOM SELECTRASTAT The function of this room thermostat is to vary a D.C. voltage signal to the amplifier that will modulate the burner to maintain a supply air temperature to satisfy space temperature.
PAGE 10
TROUBLE SHOOTING GUIDE If a service problem should occur, the following guide can be used to isolate and correct the problem. IMPORTANT: Before this heater will operate, the following conditions must be met and, therefore, should be checked before proceeding to the steps of the "Trouble Shooting" section herein. 1. Adequate supply of air into intake of the unit -- check for obstructions in intake hood and filters. 2.
PAGE 11
B. BLOWER MOTOR STARTER GOES OUT ON OVERLOAD. Probable Cause: REMEDY 1. Motor drawing too many amps. Slow blower RPM down. 2. Loose wiring. Check wire connections. 3. Low voltage to unit. Check power supply to unit. 4. Defective motor. Replace motor. 5. Belts too tight. Adjust belts for 1" deflection. 6. Defective blower bearings. Replace bearings. 7. Dirty blower wheel. Clean blower. 8. Defective starter overload. Replace starter overload.
PAGE 12
D. PILOT LIGHTS, BUT FLAME SAFETY LOCKS OUT AFTER 30 SECONDS Probable Cause: REMEDY 1. Defective flame rod. Check porcelain for cracks. Replace rod if crack is visible. 2. Pilot flame too small. Adjust pilot gas regulator to increase pilot flame. 3. Defective burner control module. If micro-amp meter measures 3 milliamps or more to module and it locks out, replace relay. ____________________________________________________________________ E.
PAGE 13
G. UNIT UNDER-FIRED (Temperature Rise Too Low) Probable Cause: REMEDY 1. Lack of gas pressure. Adjust gas pressure as stated on unit identification plate. 2. Lack of static external pressure. Adjust motor sheave to decrease blower RPM or adjust temperature rise using regulator inside unit. 3. Gas line obstruction. Remove obstruction. 4. Dirty burner. Clean burner. 5. Defective gas valve. Replace valve. 6. Improper adjustment of temperature rise.
PAGE 14
START-UP OF THE UNIT 1. Turn the remote switch to the "OFF" position. 2. Turn the main disconnect switch to the "OFF" position. 3. Remove the control cabinet cover and the blower cabinet cover. 4. Turn all the manual gas shutoff valves to the "OFF" position. 5. Check to make sure that all wiring has been completed according to the furnished wiring diagram including the installation of all field installed components. 6. Check all wiring terminals for tightness and good connection. 7.
PAGE 15
20. Open the main gas shutoff valve. Disconnect the wire from the "A4" terminal block. This will cause the unit to call for continuous high fire. 21. Check the outside air temperature and add the nameplate temperature rise to this value. Measure the discharge air temperature. Adjust the main gas pressure at the main pressure regulator until the proper discharge temperature determined above is reached. On units with the Maxitrol MR212 valve, there is no separate regulator.
PAGE 16
MAINTENANCE SCHEDULE Service and maintenance should be performed four times a year (three-month intervals) or after every 2,000 hours of operation. The following items should be checked at each inspection: A) Check wear and tension of the belt; replace if necessary. (Tension of the new belt should be re-adjusted after first two weeks of operation to compensate for stretching.) B) Check cleanliness of the burner. Clean air ports are essential for good burner operation.