ASME Thermal Expansion & Hydronic Expansion Tanks

BackStop AC & HC (ASME) Series Tanks are fixed diaphragm type, pre-pressurized expansion tanks that are used to absorb the expansion forces and control the pressure in Potable and Hydronic water systems.

Model No.	Volume (gal.)	Height	Diameter	Sys. Conn.	Wt. (lbs.)
12-AC5	3.5	14”	10”	3/4”	22
12-AC12	5	14”	12”	3/4”	28
12-AC20	8	20”	12”	3/4”	34
12-AC30	15	23”	16”	1”	64
12-AC42	22	32”	16”	1”	88
12-AC60	26	34”	16”	1”	93
12-AC80	35	45”	16”	1”	109
12-AC100	45	38”	20”	1”	148
12-AC125	60	49”	24”	1-1/2”	175
12-AC160	70	46”	24”	1-1/2”	259
12-AC180	80	49”	24”	1-1/2”	268
12-AC210	90	52”	24”	1-1/2”	283

ELBI ASME Expansion Tanks

Model No.	Volume (gal.)	Description	Diameter (inch)	Height Base Included (inch)
12-ACB8	2 GAL	ASME THERMAL EXP TANK	10.6”	7.8”H
12-ACB19	5 GAL	ASME THERMAL EXP TANK	10.6”	7.8”H
12-ACB30	8 GAL	ASME THERMAL EXP TANK	15.8”	13.1”H
12-ACB45	12 GAL	ASME THERMAL EXP TANK	15.8”	13.1”H
12-ACB80	21 GAL	ASME THERMAL EXP TANK	15.8”	33.7”H
12-ACB100	26.5 GAL	ASME THERMAL EXP TANK	19.7”	26.2”H
12-ACB140	37 GAL	ASME THERMAL EXP TANK	19.7”	32”H
12-ACB170	45 GAL	ASME THERMAL EXP TANK	19.7”	50”H
12-ACB200	53 GAL	ASME THERMAL EXP TANK	21.7”	50”H
12-ACB300	80 GAL	ASME THERMAL EXP TANK	25.6”	51”H
12-ACB400	105 GAL	ASME THERMAL EXP TANK	25.6”	60”H
12-ACB450	120 GAL	ASME THERMAL EXP TANK	25.6”	67”H

AC SERIES

Gal.	Backstop©	Amtrol	Flexcon	Watts	Wessels	Wilkins
3.5	AC5	ST-5-C	FTTA-5	DETA-5	TTA-5	WTTA-5
5	AC12	ST-12	FTTA-12	DETA-12	TTA-12	WTTA-12
8	AC20	ST-12-C	FTTA-20	DETA-20	TTA-20	WTTA-20
15	AC30	ST-30V-C	FTTA-30	DETA-30	TTA-30	WTTA-30
22	AC42	ST-42V-C	FTTA-42	DETA-42	TTA-42	WTTA-42
25	AC60	ST-60V-C	FTTA-60	DETA-60	TTA-60	WTTA-60
35	AC80	–	FTTA-80	DETA-80	TTA-80	WTTA-80
45	AC100	–	FTTA-100	DETA-100	TTA-100	WTTA-100
60	AC125	ST-80V-C	FTTA-125	DETA-125	TTA-125	WTTA-125
70	AC160	ST-120V-C	FTTA-160	DETA-160	TTA-160	WTTA-160
80	AC180	ST-180V-C	FTTA-180	DETA-180	TTA-180	WTTA-180
90	AC210	ST-180V-C	FTTA-180	DETA-180	TTA-180	WTTA-180