Installing an Electric or Hybrid AlumiTub: Deck, Enclosure and Power Options

Most of the questions we get about the Electric and the Hybrid are not about the tub. They are about where the equipment goes, how the tub meets a deck, and what the electrical run needs to be. Here are the options, with the dimensions a builder or electrician will ask for.

The short version: the tub is the same in every case, the heating and filtration equipment is detachable, and there are more ways to arrange the two than most people expect. Nothing here needs a contractor beyond an electrician for the connection.

What the equipment is

The system is a filter canister, a circulation pump and a heating coil, plumbed together on a base, plus a wall-mounted control box and a touchpad. Two 1.5 inch lines connect it to the tub: one draws water to the heater and filter, the other returns it. The return feeds one gentle 30 gpm jet, and there is no other plumbing anywhere in the tub.

Component	Dimensions
Filter canister	8" L x 8" W x 22" H
Pump	13" L x 7" W x 9" H
Heating coil	20" L x 3" W x 4" H
Control box, wall mounted	15" W x 8.5" H x 4" D
Touchpad	4" L x 1.25" W x 1.5" D, on a 5 ft cord
Plumbed together on the base	24" L x 24" W x 22" H

The control box mounts on a wall within 36 inches of the floor-mounted parts. The filter canister is the only tall item, at 22 inches, and it is also the item that needs regular access: every two weeks for a clean, and at each water change. Everything else can sit lower.

How the tub connects

Two ports through the aluminum structure, normally set vertically, one 8 inches up from the base and one 10 inches down from the rim, which puts them 20 inches apart on a standard 38 inch tub. That 20 inch spacing is the minimum. The ports can go anywhere around the tub except directly behind the firebox on a Hybrid, and the drain is positioned the same way.

If the tub is being built into a deck, the ports can be offset both vertically and horizontally so the plumbing runs below the joists rather than through them. Send us the deck elevations and we will position the ports for your framing before the tub is built.

Water lines are 1.5 inch. Electrical conduit can be the same size, or use Teck cable.

Four ways to arrange it

1. Tub on the ground, equipment in the cedar steps

The standard arrangement, and the one we designed the tub for. The equipment lives inside a weatherproof cedar step against the tub, a two-in-one step and powerhouse, with every component reachable. The tub sits on its insulated base, the steps go beside it, and setup takes 1 hour, plus the electrician for the connection. This is also the arrangement to choose if you want to be able to move the tub later.

The equipment steps are 34 inches wide, 24 inches deep and 24 inches high, in two 12 inch steps, as shown in the site prep drawings. Tubs already fitted with the earlier equipment box are not plumbed the same way, but the components are identical and the fittings can be retrofitted for the steps if you want them later. Rough in the plumbing and power where you want the steps to sit.

2. Tub on the ground against a deck cutout

The tub stays at ground level on its own base and the deck is built up to it, so the rim sits at or near deck height on one side. You keep the standard equipment steps on the ground side, the tub stays moveable, and the deck side gives you a place to sit and slide in. Most of the built-in look with none of the built-in constraints.

3. Flush or partially sunk into the deck

The tub is recessed so the rim sits at deck level, or a few inches above it, with built-in seating around it. It is the cleanest look and the easiest tub to slide into off the edge.

Three things to know before committing. The lids are not designed to be walked on, so a flush tub is a hole in the deck when the lid is off and access means kneeling or sitting to get in, or building stair access from below. The fabric lid has a skirt that has to tuck between the decking, which the cedar lid avoids. And the lid cannot be locked unless the rim sits partly above the boards. A partially sunk tub, rim a few inches proud, solves the lock and the skirt and keeps most of the look, but the raised edge is not comfortable to sit on.

The deck structure has to carry the filled weight: 3,200 lbs for the Small, 5,000 for the Standard, 7,000 for the Large, plus roughly 1,000 lbs on 44 or 48 inch builds. The drain and the two ports need planning into the framing, which is the reason to send us elevations early.

4. Custom enclosure under or beside the deck

If your setting doesn't allow for steps, such as when the tub is completely recessed in a deck, the equipment can go in an enclosure instead. You build the enclosure, we supply the parts and the site prep support. This is the arrangement our earlier equipment box was designed around, so the spec is well proven. What the enclosure needs:

• A weatherproof, protected space of 30 x 30 x 20 inches, or 24 x 24 x 22 at minimum if the filter canister can come up between the joists
• Access to the filter canister every two weeks and at water changes. The canister is 22 inches tall and can come up between joists so it is reachable from above
• The control box on a wall within 36 inches of the equipment
• Hard PVC connections in place of the flexible hoses if you prefer, for a permanent below-deck run
• The touchpad mounted in the deck surface on its 5 ft cord, or temperature managed from the Wi-Fi app with scheduled settings

In these settings the equipment can sit up to 10 feet away, provided there is no elevation change between the equipment and the tub and you supply the weatherproof enclosure. The cedar steps remain the simplest arrangement, at 1 hour of setup plus the electrician; the enclosure is for settings where steps will not fit.

Heights, so the deck comes out right

• Tub: 38 inches standard, 44 available on Wood Fired and Hybrid, 44 or 48 on Electric
• Rigid insulation beneath adds 2 to 4 inches depending on thickness; the recommended 3.5 inch base adds 3.5
• Bench height inside is 13.5 inches at 38 and 44. On a 44 inch Standard, two of the four seat sections can be raised to roughly 20 to 22 inches
• Fabric lid: 4 inches thick at the center, tapering to 3 at the edges
• Accessory steps: 24 inches wide, 20 deep, 20 high, in two 10 inch risers
• Equipment steps: 34 wide, 24 deep, 24 high, in two 12 inch steps
• Equipment height inside a custom enclosure: 22 inches, set by the filter canister
• On a Hybrid, chimney and cap: 58 inches above the tub, 96 inches from the ground on a standard build, and at least ten feet clear of anything overhanging

Power: 120V and 240V, and switching later

A Wood Fired with the optional filtration system runs on a dedicated 15 amp, 120V outdoor outlet within 13 feet of the equipment steps, with a plug-in cord. An Electric or Hybrid heater runs on a dedicated 240V, 30 amp, 4kW circuit with an 18 amp draw, installed by a certified electrician. The standard 4kW heater suits most tubs. Where a tub will rely on electric heat alone, with no wood fire, somewhere that stays well below freezing, there is an optional 5.5 kW element; it draws about 23 amps on its own and needs a larger circuit than the standard 30 amp, which your electrician sizes from the heater specification, so tell them before the run goes in.

The two are not separate systems. A 120V filtration setup can be converted to 240V heating later using the same equipment: a replacement fuse and a hardwired GFCI-protected connection in place of the plug-in cord, around ten dollars in parts plus the electrician's time. So a Wood Fired with filtration can become a Hybrid without replacing anything, which is the reason we suggest running the 240V circuit to the site at the outset even if you are starting on 120V.

Run the circuit before the tub arrives. Trenching is far easier before the tub is sitting there, and the electrician makes the connection on delivery day.

Freeze protection, and what it does not do

When the temperature sensor reads 44°F, freeze protection runs the pump automatically and keeps the water circulating so it cannot freeze, for as long as the unit has power. It circulates rather than heats. That is what makes an unattended property workable through winter.

It gives no protection in a power outage, so if one is likely, drain the tub. Water held at 104°F takes time to cool, so there is time to do it before the tub is at risk.

The system heats. It does not cool. The lowest setting is 50°F, and the heater only comes on if the water drops below the set point. If summer sun warms the water above what you have set, there is no chilling function to bring it down; shade, the lid, and a cold top-up are the tools.

What to send us

If you are building the tub into a deck or a custom enclosure, three things let us position the ports and drain before the tub is built: the deck elevation relative to grade, where you want the equipment to sit, and where the steps or access will be. We will send dimensioned drawings back, and the site prep support that goes with them. Everything else, from the power run to the base, is covered in how to prepare for arrival.

Common questions

Can an electric hot tub be built into a deck?

Yes, flush, partially sunk, or on the ground against a deck cutout. The deck must carry the filled weight, 5,000 lbs on a Standard, and the two 1.5 inch plumbing ports and the drain can be offset to run below the joists if you send the deck elevations before the tub is built. Flush installs trade lid locking and easy access for the cleanest look.

How much space does the heating and filtration equipment need?

In the standard cedar equipment steps, none beyond the steps themselves: 34 inches wide, 24 deep and 24 high, in two 12 inch steps. In a custom enclosure, a weatherproof space of 30 by 30 by 20 inches, or 24 by 24 by 22 at minimum, with the control box wall mounted within 36 inches and the filter canister reachable for its two-weekly clean.

Does the equipment have to sit right beside the tub?

No. The standard arrangement puts it in the cedar steps against the tub. If your setting doesn't allow for steps, such as a tub completely recessed in a deck, it can sit up to 10 feet away with no elevation change, in your own weatherproof enclosure, using hard PVC in place of the flexible hoses if preferred.

Can a 120V hot tub be converted to 240V later?

Yes, with the same equipment. A 120V filtration setup converts to 240V heating with a replacement fuse and a hardwired GFCI-protected connection in place of the plug-in cord, around ten dollars in parts plus an electrician. That is how a Wood Fired with filtration becomes a Hybrid without replacing anything.

What does freeze protection do on an electric hot tub?

It runs the pump automatically when the sensor reads 44°F, circulating the water so it cannot freeze, for as long as the unit has power. It circulates rather than heats and gives no protection in an outage, so drain the tub if one is likely. Water held at 104°F takes time to cool, which leaves time to drain it.

Can an electric hot tub cool the water in summer?

No. The system heats only. The lowest setting is 50°F and the heater comes on only if the water drops below the set point, so if sun warms the water above it, shade, the lid and a cold top-up are the ways to bring it down.