Low flow vertical hot tub spa heaters will usually be mounted vertically like a juice can on the side of the control box. Some heaters have replaceable elements but most don't.
Caldera spas Low Flow heater Assembly for hot tub spas - $138.40
Caldera Spas, Etc.
Stainless heater assembly
3/4" barb x 3/4" 90° barb
5.5kW/240v
Caldera Spas and others
No pressure switch
Part # Description
46-238-1546 Low flow heater assembly Ca... More Info
Discovery Spas Heater Assembly for hot tub spas - $151.58
Discovery Spas
Vertical 3" x 6-5/8" housing
1" barb inlet/outlets on opposite sides
Ready for an electrical box to be mounted on it
Includes a 5.5kW/240v, EP element.
26-00105
Par... More Info
DM, Vita Spas heater assembly for hot tub spas - $144.25
DM, Vita Spas
E2400-0127ET
Vertical heater assembly
3" x 11" with 3/4" barb x 3/4" 90°
barb inlet/outlets
4.0kW/240v
Part # Description
46-238-1560 Lo flow heater 4.0kW/240v... More Info
Gatsby Spas vertical heater for hot tub spas - $166.80
Gatsby Spas Vertical heater assembly
3" x 6.469" housing
5.5kW/240v, 1" 90° barb tailpiece, no box
Part# Description
46-371-1277 Low flow assembly, Gatsby, 5.5kW/240v, 26-00155
4... More Info
Hurricane Proshield G heater assembly for hot tub spas - $124.25
Hurricane, Proshield model G & Others
Leisure bay,watson's, rec warehouse
Vertical 3" x 9" housing
1" barb inlet/outlet
5.5kW/240v element
1/8"npt p/s tap located between heat... More Info
Hydro-Quip Versi-Heat assembly for hot tub spas - $222.71
Hydro-Quip Versi-Heat remote heater replacement
26-08159
4.0kW/240v.
Fits Hydro-Quip 9400, 9600 series controls
1/8"npt pressure switch tap
1" barb inlet and 1" 90° barb tailpiece,... More Info
Leisure Bay & Others heater assembly for hot tub spas - $154.79
Leisure Bay spas hot tubs & Others
E2550-0202ET
Vertical heater assy
1" barb inlet/outlet same side,
3" x 9" dimensions,
Rated at 5.5kW/240v.
Similar to Hurricane except that the
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Maax Spas heater assembly for hot tub spas - $261.59
Maax Spa
26-08145
Vertical heater assembly
3" x 6.469" housing, 4.0kW/240v
1" 90° spocket tailpiece 1" barb
36" cord w/terminals (10/3 so)
pressure switch & plastic 4 x ... More Info
Nu-Wave Spas heater assembly for hot tub spas - $167.70
Nu-Wave Spas
E2400-0007
9.42" x 3" stainless steel manifold
1-1/2"QD heater unions
4.0kW/240v.
Found in Nu-Wave Spas.
Part # Description
46-238-1550 Low flow heater, 4.0kW/240v
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Saratoga Spas heater assembly for hot tub spas - $149.49
Saratoga Spas
20-00540
Stainless steel 3" x 13-1/2"
4kW/240v element,
3" x 90° 3/4" barb tailpieces
(2) 10-32 x 3/8" mounting stud
1/8"npt pressure switch tap
Part... More Info