DTH Common Parts

DTH Heater Replacement Options

There are not many parts still available for this 40+ year old heater series. Due to the original design of this heater, it is NOT possible to simply attach a new burner head onto the existing tubing. A new heater is required to replace the old unit.

A DES3 Series with U-Bend package is a great replacement.

DTH Parts by Year

Part Description	DTH	DTH-2	DTH-2	DTH-2 125, 150 MBH	DTH-3 125 MBH	DTH-3 150 MBH
	Prior ----> 11/1986	11/1986 to 01/1987	01/1987 to 04/1992	1988 to1989	1989 to1994	1990 to1994
Inducer Fan Blower	N/A	TP-55A	TP-55A	TP-55A	TP-55A	TP-55A
Circuit Board	N/A	N/A	N/A	N/A	TP-78D & TP-390	TP-78D & TP-390
Radiant Sensor	TP-64	TP-64	TP-64	TP-64	TP-64	TP-64
Ignition Device	TP-50A	TP-50A	TP-50A	TP-50A	TP-50A	TP-50A
Gas Valve (Nat)	N/A	N/A	N/A	N/A	TP-107 VR4205M-1324	TP-79 VR4205M-1308
Gas Valve (LP)	N/A	N/A	N/A	N/A	TP-107P VR4205M-1357	TP-107P VR4205M-1357
Control Voltage	120V	120V	120V	120V	120V	120V
IOM Link

Pressure Switch

Model	Year Range		40 MBH	50-75 MBH	100 MBH	125 MBH	150 MBH
DTH	Prior ----> 11/1986	Switch 1 N.O. Switch 2 N.C.	N/A N/A	N/A N/A	N/A N/A
DTH-2	11/1986 to 01/1987 01/1987 to 04/1992	Switch 1 N.O. Switch 2 N.C.	TP-264B TP-60C	TP-264B TP-60C	TP-264B TP-60C
DTH-2	1988 to 1989	Switch 1 N.O. Switch 2 N.C.				TP-264B TP-60D	TP-264B TP-60D
DTH-3	1989 to 1994	Switch 1 N.O. Switch 2 N.C.				TP-264B TP-60D	TP-264B TP-60D

Note: For heaters with (2) pressure switches, the burner switch in the blower compartment is a normally open switch and the exhaust switch in the gas valve compartment is a normally closed switch.