Howden Roots Metric Series, Installation, Operation And Maintenance Manual

ISRB_2002 GEA 19171 Roots URAI 

Page 9 of 32



  Howden Roots 

does NOT

 recommend the use of 

automotive type lubricants, as they are not formulated 

with the properties mentioned above. 

Roots URAI-DSL blowers with splash lubrication/oil 

on each end. No grease.



  The specified and recommended oil is Roots Synthetic 

Oil of correct viscosity per Table 2, page 16. 



  The lubrication should be changed after initial 100 hours 

of operation. 



  The proper oil level should be half way or middle of the 

sight gauge when the blower is not operating. 

DO NOT 

OVERFILL OIL SUMP/S

as damage to the blower may 

occur.



  The oil level should not fall below the middle of the site 

gauge when the blower is idle. 



  The lubrication/oil level may rise or fall in the gauge 

during operation to an extent depending somewhat on 

oil temperature and blower speed. Proper service 

intervals of the oil thereafter are based on the discharge 

air temperature of the blower. Please refer to the 

information below to “How to properly determine the oil 

service intervals” shown on this page. 



  Unless operating conditions are quite severe, a weekly 

check of the oil level and necessary addition of lubricant 

should be sufficient. During the first week of operation, 

check the oil levels in the oil sumps about once a day, 

and watch for leaks. Replenish as necessary. 



  If you choose to use another oil other than the specified 

and recommended Roots Synthetic Oil, use a good 

grade of 

industrial type

non-detergent, rust inhibiting, 

antifoaming oil and of correct viscosity per Table 2, page 

16. 



  Roots does 

NOT

recommend the use of automotive type 

lubricants, as they are not formulated with the properties 

mentioned above. 

How to properly determine the oil service intervals. 

Normal life expectancy of the specified and 

recommended Roots Synthetic Oil is approximately 

6000 hours with an oil temperature of 180°F (82°C) or 

less. As the oil temperature increases by increments of 

15°F (8°C), the oil life is reduced by half for each 15°F 

(8°C) increase. Example: Oil temperatures of 195°F 

(90.5°C) will produce a life expectancy reduced by half 

or 3000 hours oil service life. 
Normal life expectancy of petroleum based oils is about 

2000 hours with an oil temperature of about 180°F 

(82°C). As the oil temperature increases by increments 

of 15°F (8°C), the life is reduced by half for each 15°F 

(8°C) increase. Example: Oil temperatures of 195°F 

(90.5°C) will produce life expectancy reduced by half or 

1000 hours oil service life. 

NOTE:

To estimate oil temperature, multiply the 

discharge temperature of the blower by 0.80. Example: if 

the discharge air temperature of the blower is 200° F, it 

is estimated that the oil temperature is 160° F 

For Units with grease lubricated drive end bearings. 
URAI AIR (Non GAS) blower grease specifications. 



  When servicing drive end bearings of a AIR (Non Gas) 

blower, use the specified and recommended Shell 

Darina SD 2 NLGI #2 product code 5067628. 



  For grease lubricated drive end blowers see page 16, 

table 4, regarding specified greasing intervals. 



  Lithium based greases are not compatible with the 

specified and recommended Shell Darina SD 2 grease 

used when assembling the blower. 

Lithium based 

grease is not approved for any ROOTS blowers.



  Table 4 page 16 has been prepared as a general 

greasing schedule guide based on average operating 

conditions. More frequent intervals may be necessary 

depending on the grease operating temperature and 

unusual circumstances. 

URAI-G blower grease specifications. 



  When servicing drive end bearings of a URAI-G blower, 

use the specified NLGI #2 premium grade aluminium 

complex† grease, GE P/N T20019001. Lithium based 

greases are not compatible with the specified and 

recommended Roots Synthetic Grease used when 

assembling a GAS blower. 

Lithium based grease is 

not approved for any Roots blowers.



  The lubricants selected must be compatible with the 

gas. 

†Roots Synthetic Oil is superior in performance to petroleum 

based products. It has high oxidation stability, excellent 

corrosion protection, extremely high film strength and low 

coefficient of friction. Typical oil change intervals are increased 

2-3 times over petroleum based lubricants. Also, Roots 

Synthetic Oil is 100% compatible with petroleum based oils. 

Simply drain the oil in the blower and refill the reservoirs with 

Roots Synthetic Oil to maintain optimum performance of your 

Roots 

ISRB_2002 GEA 19171 Roots URAI.indd   9

17/09/2015   12:52