Security Chimneys Secure Temp ASHT, Manual

Installation

Assembly always requires the male coupler to be 

positioned upwards. Size the chimney in accordance 

with the appliance instruction manual. Map out the 

chimney path closest to the heating unit. Prior to 

installation, consult the detailed installation manual 

included with the support components.

SAFETY

Security Chimneys International’s Secure Temp 

ASHT chimneys can be installed as close as 2 

inches to combustible materials, regardless of 

the diameter to be used. Radiation shields and 

appropriate supports must be used to maintain 

a safe clearance as the chimney passes through 

floors and combustible partitions.
Some radiation shields in the Secure Temp ASHT 

line have been designed specifically for use with 

wood-burning fireplaces. For the use of Secure 

Temp ASHT with manufactured wood fireplaces, 

refer to the instructions of these products.

LOADBEARING CAPACITY

Maximum 

height

Ø int.

5"

6"

7"

8"

10"

Floor support

32' 32' 32' 32' 32'

Tee support

63' 63' 55' 48' 39'

Adjust. tee/

wall support

63' 63' 55' 48' 39'

Roof support

42' 34' 27' 24' 20'

Offset 

support

--

28' 24' 20' 14'

Sq. cathedral 

support

--

60' 50' 45' 35'

Finishing 

support

--

75' 65' 59'

--

Adj. square 

support w/ 

faming arms 

and coupler

--

27' 22'

--

--

Offset/Wall 

support

--

28' 24' 20' 14'

Reduced 

Clearance 

support 

--

60' 50' 45'

--

SIZE OF OPENINGS*

Hole size 

(framing)

Ø int.

5"

6"

7"

8"

10"

Floor 

support

11-

3/8"

12-

3/8"

13-

3/8"

14-

3/8"

16-

3/8"

Sq. 

cathedral 

support

--

14-

3/8"

14-

3/8"

14-

3/8"

--

Finishing 

support

14-

3/8"

14-

3/8"

14-

3/8"

14-

3/8"

--

Roof 

support

11-

3/8"

12-

3/8"

13-

3/8"

14-

3/8"

16-

3/8"

Wall 

thimble

11-

3/8"

12-

3/8"

13-

3/8"

14-

3/8"

16-

3/8"

Firestop

11-

3/8"

12-

3/8"

13-

3/8"

14-

3/8"

16-

3/8"

Reduced 

Clearance 

support

--

10"

11"

12"

--

SECURE TEMP

ASHT GENERAL SPECIFICATIONS

Ø int.

Ø ext.

Insulation 

thickness

Weight 

lb./ft.*

Twist-Lock 

assembly

Clearance to 

combustible

5"

7"

1"

4.1

YES

2"

6"

8"

1"

5.2

YES

2"

7"

9"

1"

6.4

YES

2"

8"

10"

1"

7.2

YES

2"

10"

12"

1"

8.9

YES

2"

Temperature Rating

Period of Operation

538°C (1000°F(

Max. continuous

760°C (1400°F)

Brief forced fired

1150°C (2100°F)

3 x 30 minutes, tested

Residential furnace and 

water heater

Chimney with several 

fireplaces

10

9

11

9

8

8

3

12

13

5

7

3

3

8

11

5

1

Chimney on a wood 

stove

16

14

15

3

17

18

19

6

7

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