Shopping list · prototype 0
What to order for the Solo Starter.
One orderable line per thing to buy, grouped by build stage. Buy stage 1 first: the bench build tells you whether the design works before anything goes near a bed. Every line maps to a role in the parts catalog, so you can swap any product for one that meets the same requirement.
- Stage 1 · bench
- €1,083.90
- Stage 2 · bed
- €261.86
- Total
- €1,345.76
- Estimated lines
- 48
Prices change. Checked on (Germany / EU, prices incl. VAT). Shipping is not included. Lines marked estimate have no confirmed price. Re-check every price before you order.
Notes on this list
- Shipping is not included (expect ~6 EUR per shop; ~8 shops). Prices change; re-check before ordering.
- Loop size is 13/10 mm (ID 10 / OD 13) everywhere except the cold-plate barbs and the mat's 4 mm channels.
- Metals: brass/copper only (G1/4 fittings, QD3, sensors, copper cold plates). No aluminium in the wet path (parts.toml).
- Pump + 6 fans must stay inside the kit's 25 W per-zone overhead budget: run the DDC at <= 50 % and the fans at quiet speed.
- Sensors match the firmware (board.rs): one ADS1115 @ 0x48, zone 0 uses ch0 = water (inline NTC) and ch1 = TEC hot face
- (bead NTC). Future, not bought: parts.toml also asks for water in AND out, dual NTCs per cold plate and an NTC on every
- heatsink; add them when board.rs reads more channels.
Stage 1: bench build
Everything for the bench build: no bed, a 10 l water container as the thermal load.
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Mean Well GST280A24-C6P (24 V / 11.67 A, IEC C14, desktop)Reichelt no. MW GST280A24. Output is a 6-pin Molex plug: see the mating-connector line. | 1 | 94.80 | 94.80 | Reichelt |
| Mean Well GST90A12-P1M (12 V / 6.67 A, IEC C14, desktop)Reichelt no. MW GST90A12. 5.5 x 2.5 mm barrel plug, center positive. | 1 | 30.40 | 30.40 | Reichelt |
| RD DPS5020 programmable buck module, communication version (USB-BT)Amazon.de only (no German electronics distributor carries it). US listings ~USD 64-107. Buy the communication version: it exposes the TTL UART used for Modbus. Measure output ripple (parts.toml asks). | 1 | 75.00 | 75.00 | Amazon.de |
| Automotive relay 12 V coil, 30/40 A, 1 changeover (SPDT, ISO mini, 5-pin)1x zone enable relay (coil through the cutoff chain, load on NO) + 2x SPDT wired H-bridge style for polarity (parts.toml allows this instead of one 20 A DPDT). TECs see <= 14 V, inside the 14 V automotive rating. Price from the category page, exact part not pinned. | 3 | 5.49 | 16.47 | Conrad |
| Relay socket for ISO mini relay with pigtail leads (>= 2.5 mm2 load leads) | 3 | 3.00 | 9.00 | Conrad |
| Inline ATO/ATC blade fuse holder, waterproof, 2.5-4 mm2 leadsPer-zone DC fuse in the TEC path (parts.toml role polarity_relay). | 1 | 4.00 | 4.00 | Conrad |
| ATO blade fuse 20 A (pack of 10) | 1 × 10 | 3.50 | 3.50 | Conrad |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Raspberry Pi Pico 2 (RP2350), SC1631Without headers; see the pin-header line. | 1 | 4.90 | 4.90 | Reichelt |
| ADS1115 4-channel 16-bit ADC breakoutAddress 0x48 (ADDR to GND). ch0 water, ch1 hot face; ch2/ch3 belong to zone 1 (Duo kits). | 1 | 5.60 | 5.60 | Berrybase |
| Alphacool Eiszapfen temperature sensor flat G1/4, 10k NTC (water, return line)ADS ch0. Screws into a free G1/4 port (the T-adapter in the return line, WIRING.md). A second one for water-in is future. B value not published: calibrate in an ice bath and at ~40 C. | 1 | 10.98 | 10.98 | Alphacool |
| 10k NTC epoxy bead thermistor, B ~3950, with leads (TEC hot face, + 2 spares)ADS ch1: one on the heatsink base of the middle TEC, clamped with thermal paste. Two spares for calibration losses. Calibrate like the inline sensor. | 3 | 1.20 | 3.60 | Reichelt |
| Adafruit SHT45 breakout (room temperature / humidity for the dew-point guard)Read by the ESP32-S3 hub (02-electrical-safety.md, Condensation). | 1 | 13.00 | 13.00 | Berrybase |
| Metal film resistor 10 kOhm 0.1 % (NTC divider references)2 used (ch0, ch1) + 2 spares. Not the same as the generic 10 k pull resistors. | 4 | 0.40 | 1.60 | Reichelt |
| Bimetal thermostat, normally closed (Oeffner), 50 C, auto-reset (cold plates)Select Oeffner + 50 C. Uncertified. Test every unit with a hot-air gun and a thermometer; consider one spare. | 3 | 2.98 | 8.94 | sensorshop24 |
| Bimetal thermostat, normally closed (Oeffner), 80 C, auto-reset (heatsink bases)Select Oeffner + 80 C. All six in series in the zone-relay coil circuit (12 V, coil current only). | 3 | 2.98 | 8.94 | sensorshop24 |
| HW group Sensor WLD Relay 1W-UNI (incl. 2 m WLD sensing cable A)Relay output signals water OR disconnected cable (fault output). Price not shown on the page. Wire the contact so dry = LOW at GP21 with the 10 k pull-up (WIRING.md). Kept after a second search (2026-10-11): the cheap relay-output leak modules (ATO, Amazon 12 V modules, Winland WaterBug) only alarm on water and do not report an open or unplugged sensor cable, so a broken wire would read as dry. The WLD relay also switches on cable disconnect, which matches the firmware input (HIGH = leak or open wire). Cheaper fail-safe fallback: an NC float switch in the drip tray wired to GND (dry = LOW, float lifts or wire breaks = HIGH), but it only reacts to ~1 cm of standing water, not to drops. | 1 | 95.00 | 95.00 | BellEquip (AT) |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Espressif ESP32-S3-DevKitC-1-N8R818.90 EUR (BerryBase ADA5336) seen in a related-items block; check the SKU is N8R8. Mouser EU lists it at ~11-13 EUR net. | 1 | 18.90 | 18.90 | Berrybase |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Peltier module 40 x 40 x 3.8 mm, 6.0 A, 15.4 V, 51.4 W (Reichelt TECB 1)Sold singly, in stock. Specs close to the TEC1-12706 the model uses; get the datasheet from the product page and compare Qmax/R. TEC1 127 05 (23.95 EUR) is the limited-stock alternative. | 3 | 28.40 | 85.20 | Reichelt |
| Copper water block 40 x 40 mm for Peltier modules, barbed portsCopper, not aluminium (no mixed metals). Barbs are ~8 mm OD: see the reducer line. Lap flat if needed. | 3 | 10.00 | 30.00 | Amazon.de |
| Arctic Freezer 36 CO tower cooler (2x 120 mm PWM, continuous-operation fans)One per TEC (hot side). CO fans are rated for 24/7. Measure the real K/W (kit assumes 0.11 K/W per zone). Socket mounts do not fit a TEC: see the mounting line. | 3 | 22.90 | 68.70 | Caseking |
| Alphacool Laing DDC310 Single Edition, silver (12 V, tach)Pump without top: mounts into the Eisstation DDC reservoir below. Low-noise DDC; verify head (>= 1 m), tach wire and PWM on the product page. Tach to a Pico input via the 10 k pull-up. | 1 | 68.58 | 68.58 | Aquatuning |
| Alphacool Eisstation DDC - Solo reservoir (mounts directly on the DDC pump, G1/4)Cheapest reservoir found in a German shop that takes the bare DDC310 (so no separate pump top). Smaller than the ~0.5 L target in parts.toml: fine for prototype 0 (the bench loop has the 10 l container on a coil, the bed loop adds the mat volume); verify volume and fill port on arrival. Plastic (non-metallic) wall, so the capacitive level sensor works if the wall is <= 20 mm. Upgrade path: Watercool HEATKILLER Tube 200 DDC (~500 ml glass, ~115 EUR). | 1 | 34.63 | 34.63 | Aquatuning |
| XKC-Y25-NPN non-contact capacitive level sensor, 5-12 V (LOW_WATER)Taped to the reservoir wall at the minimum level (non-metallic wall <= 20 mm). Listings give 'output high level = VCC', so it may drive its supply voltage: power it at 5 V (not 12 V), put a divider (e.g. 2.2 k / 3.3 k) into GP22, and measure the idle output before connecting. Wanted: LOW = water present (level OK), HIGH = low water or broken wire (WIRING.md). Verify the polarity of your unit; add an inverter if it is reversed. | 1 | 8.00 | 8.00 | Amazon.de |
| YF-S401 hall flow sensor, 98 Hz per L/min, 7 mm barbs (for 6 mm ID hose)Matches the prebuilt Solo UF2: FLOW_HZ_PER_LPM = 98 (Q [L/min] = f [Hz] / 98, per the listing). Range 0.3-6 L/min, +-10 %: our 0.4-0.6 L/min is at the low end, so calibrate with a measuring jug and a stopwatch. Below 0.3 L/min it reads low or zero, so the 0.15 L/min interlock trips early (safe side). Output is open-collector style: power at 5 V, signal to GP14 with the 3.3 V pull-up (measure the idle level first; use a divider if it shows 5 V). Flow direction arrow matters. Upgrade: Aqua Computer mps flow 100 (G1/4, 20-100 l/h, no moving parts, ~55 EUR): its alarm output can be set to an rpm signal via USB, but the exact pulses per litre are not documented for it (the high flow NEXT manual gives 100 l/h = 1000 rpm), so it needs a measured factor and a source build with a new FLOW_HZ_PER_LPM. | 1 | 4.00 | 4.00 | TinyTronics (NL, ships to DE) |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| IEC C13 mains cord with Schuko plug, 1.8 mBoth GST supplies ship without a mains cord. Price from the search page, exact item not pinned. | 2 | 4.80 | 9.60 | Reichelt |
| Molex Mini-Fit Jr 6-pin receptacle + crimp terminals (mates the GST280 C6P plug)Or cut the DC plug off (DC side only, never the mains side) and put ferrules on the 16 AWG leads. Check the pinout in the GST280A datasheet. | 1 | 4.00 | 4.00 | Reichelt |
| DC barrel jack 5.5 x 2.5 mm to screw terminal adapterFor the GST90A12 12 V output. | 1 | 1.50 | 1.50 | Berrybase |
| Elecrow UART TTL to RS485 converter, half duplex, 3.3-5 V (Modbus to the DPS)One at the DPS UART, one at the Pico (WIRING.md: one RS-485 bus). Stand-in for a MAX3485 module; if the module switches direction itself, GP6 (DE) stays unused. Price (1.90 EUR) seen in a related-items block, not on its own product page. | 2 | 1.90 | 3.80 | Berrybase |
| DC-DC buck converter 12 V to 5 V, >= 3 A (powers Pico 2, ESP32-S3, sensors)Fed from the 12 V aux supply. Pico 2 via VSYS, ESP32-S3 via its 5 V pin; common GND at the star point. | 1 | 6.00 | 6.00 | Berrybase |
| 4-channel logic-level MOSFET switch module (3.3 V input, >= 5 A per channel)Low-side drivers: GP10 zone relay coil, GP11 both polarity coils, GP12 pump, GP13 fans. Add the external 10 k pull-downs (WIRING.md); do not rely on the module's own. | 1 | 7.00 | 7.00 | Amazon.de |
| 1N5408 rectifier diode (flyback across each relay coil, pack of 10)1N4007 works as well for 12 V relay coils. Skip if the relays you buy have a built-in diode (then mind the coil polarity). | 1 × 10 | 1.50 | 1.50 | Reichelt |
| Pin header set for Raspberry Pi PicoBerryBase RPIP-PINH, 0.50 EUR seen on berrybase.at. | 1 | 0.50 | 0.50 | Berrybase |
| Resistor 10 kOhm 1/4 W (pull-ups / pull-downs, pack of 100) | 1 × 100 | 1.50 | 1.50 | Reichelt |
| Resistor 4.7 kOhm 1/4 W (MOSFET gate pull-downs, DS18B20 pull-up; pack of 100)RP2350 erratum E9: external pull-downs should be <= 8.2 k, so use 4.7 k on the driver inputs (WIRING.md still says 10 k: open item). | 1 × 100 | 1.50 | 1.50 | Reichelt |
| 1N5819 Schottky diode (Pico VSYS / ESP32 5 V OR-ing, pack of 10)Lets USB and the 5 V buck feed the boards without back-feeding each other. | 1 × 10 | 1.00 | 1.00 | Reichelt |
| Resistor 120 Ohm (RS-485 termination) + 2.2 k / 3.3 k (spare dividers for 5-12 V signals) | 1 | 1.00 | 1.00 | Reichelt |
| Perfboard 160 x 100 mm + 2-pin/3-pin PCB screw terminals (5.08 mm, ~20 pcs) | 1 | 9.00 | 9.00 | Reichelt |
| Raspberry Pi Debug Probe (optional, for defmt logs and flashing)Optional; a second Pico 2 with debugprobe firmware works too. WIRING.md bring-up step 1 uses it. | 1 | 12.20 | 12.20 | Berrybase |
| Single-core flexible wire H07V-K 2.5 mm2, red, per m (TEC path)TEC path carries up to 15 A: >= 2.5 mm2 from DPS through fuse, relays to the TECs. | 5 | 0.80 | 4.00 | Reichelt |
| Single-core flexible wire H07V-K 2.5 mm2, black, per m (TEC path) | 5 | 0.80 | 4.00 | Reichelt |
| Stranded hook-up wire 0.25-0.5 mm2, assorted colours (signals, coils, sensors) | 1 | 12.00 | 12.00 | Reichelt |
| WAGO 221-415 lever connector, 5-conductor, up to 4 mm2Price not shown in the fetched page. Use for the 24 V / 12 V / GND star point. | 10 | 0.95 | 9.50 | Reichelt |
| Knipex ferrule assortment, insulated, 0.5-2.5 mm2 (400 pcs) | 1 | 14.10 | 14.10 | Reichelt |
| Dupont jumper wires F-F / M-F (40 each) and heat-shrink assortment | 1 | 8.00 | 8.00 | Berrybase |
| TEC sandwich mounting: M3/M4 threaded rod, nuts, springs, 3 mm aluminium backplateEven clamping pressure on the ceramic; insulating washers so the block and cooler are not shorted through the screws. | 3 | 5.00 | 15.00 | Amazon.de |
| Arctic MX-6 thermal paste, 4 g6 TEC faces + NTC beads. | 1 | 6.90 | 6.90 | Caseking |
| Barbed hose reducer 10 mm to 6 mm, straight (13/10 loop to the YF-S401) + 20 cm 6 mm ID tube + clampsKeep 5 cm of straight tube before the sensor. Plastic (PP/POM) reducers, no aluminium. | 2 | 2.50 | 5.00 | Amazon.de |
| Alphacool Eiszapfen 13/10 mm compression fitting G1/4, deep black, six-packReservoir, pump outlet, flow sensor, T-adapter (2), cold-plate reducers; spares for the bed stage. Brass. | 2 × 6 | 35.62 | 71.24 | Aquatuning |
| G1/4 T-adapter (3x inner thread), for the inline water temperature sensor | 1 | 5.00 | 5.00 | Alphacool |
| Phobya EPDM tube 13/10 mm, black, per mPrice shown as recommended accessory on the fittings page. 3 m loop + 5 m coiled in the 10 L bench container as the heat exchanger. Check per-m vs per-pack unit at checkout. | 8 | 4.49 | 35.92 | Aquatuning |
| Reducers / short 10/8 mm tube and hose clamps to the cold-plate barbsCold plates in series; match the barb OD of the blocks you receive. | 1 | 10.00 | 10.00 | Aquatuning |
| Aqua Computer Double Protect Ultra, 5 l canister (ready-mixed coolant with inhibitor)Distilled water + inhibitor in one. Enough for the loop plus the mat; replace yearly. | 1 | 32.90 | 32.90 | Aqua Computer |
| Distilled water 5 l (flushing and leak test)Any drugstore. The bench container (10 l) can be plain tap water: the coil keeps it out of the loop. | 1 | 3.00 | 3.00 | Amazon.de |
| Self-adhesive closed-cell insulation tape (Armaflex type), 3 mm x 50 mm x 15 mWrap cold plates and short lines against condensation (02-electrical-safety.md). | 1 | 12.00 | 12.00 | Aquatuning |
| Electronics enclosure, ABS ~250 x 200 x 100 mm (dry compartment, above water level) | 1 | 25.00 | 25.00 | Reichelt |
| Drip tray: plastic storage tray ~60 x 40 cm, low rim (holds the wet parts and the leak cable) | 1 | 10.00 | 10.00 | Amazon.de |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Insulated cool box ~10 l (thermal load: the 'sleeper' for bench tests)Filled with water; the 5 m tube coil lies in it. Lid with two holes for the lines. | 1 | 25.00 | 25.00 | Amazon.de |
| DS18B20 waterproof temperature probe, 1 m cable (bath temperature, logged by the hub)On the ESP32-S3 (ESPHome dallas) with a 4.7 k pull-up. With the coil, the firmware NTC sees only loop water; this logs the 10 l bath in Home Assistant. | 1 | 3.50 | 3.50 | Berrybase |
| Power resistor 1 Ohm, >= 100 W, aluminium housing (DPS bring-up dummy load)WIRING.md bring-up step 3: test the DPS on a 1 Ohm load before any TEC, set to 1-2 A from the DPS front panel (not from the Pico, which would request up to 15 A = 225 W into 1 Ohm). Mount on a heatsink. | 1 | 8.00 | 8.00 | Reichelt |
Subtotal bench €1,083.90
Stage 2: bed
Added when you move from the bench to the bed.
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| HW group WLD sensing cable A, extra length for the hub-side couplingsOptional: route under the QD3 couplings; the included 2 m covers the drip tray. | 1 | 25.00 | 25.00 | BellEquip (AT) |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Koolance QD3 no-spill female, straight, 13/10 mm, black~0.2 ml freed per disconnect (Koolance spec), inside the 0.5 ml target. Hub side. | 2 | 22.98 | 45.96 | Aquatuning |
| Koolance QD3 no-spill male, straight, 13/10 mm, blackThe 16/10 male is listed at 21.98 EUR; 13/10 assumed the same. Mat side. | 2 | 21.98 | 43.96 | Aquatuning |
| DIY mat: PVC tube 4 mm ID / 6 mm OD (fabric-reinforced if available), per mDocumented DIY build (parts.toml water_mat): ~30 m in parallel channels, not one serpentine. 8 mm was too stiff in that build. A generic water-perfused cooling pad bought in the EU is an acceptable v0 stopgap (never a commercial bed system's pad as a dependency). | 30 | 1.20 | 36.00 | Amazon.de |
| DIY mat: foam topper 90 x 200 cm, ~4 cm (channels cut in) | 1 | 45.00 | 45.00 | Amazon.de |
| DIY mat: 1-to-8 manifold, 10 mm inlet to 8x 4 mm barbs (supply + return)Must be pressure-rated (brass or PP), not an aquarium air manifold. Parallel channels keep flow resistance low. | 2 | 12.00 | 24.00 | Amazon.de |
| Item | Qty | Unit € | Line € | Shop |
|---|---|---|---|---|
| Phobya EPDM tube 13/10 mm, black, per m (insulated bed lines, 2 x 3 m) | 6 | 4.49 | 26.94 | Aquatuning |
| Closed-cell tube insulation for 13 mm OD tube, 2 m piecesAgainst condensation and heat loss on the hub-to-mat lines. | 3 | 5.00 | 15.00 | Amazon.de |
Subtotal bed €261.86
Tools
Not in the totals; qty 0 means you probably own it already.
| Item | Qty | Unit € | Shop |
|---|---|---|---|
| Digital multimeter (CAT III) | 0 | 30.00 | Reichelt |
| DC clamp meter (Hall, >= 20 A DC) for TEC current checksAC-only clamp meters do not read the TEC current. | 0 | 45.00 | Reichelt |
| Ferrule crimping tool (0.25-6 mm2) | 0 | 25.00 | Reichelt |
| Soldering iron + solder | 0 | 40.00 | Reichelt |
| Hot-air gun (bimetal cutoff test) | 0 | 25.00 | Amazon.de |
| Reference thermometer with probe, 0.1 C resolution (NTC calibration) | 0 | 15.00 | Amazon.de |
| Plug-in mains power meter (energy monitor socket)Measures real wall power of both supplies during bench tests. | 0 | 15.00 | Reichelt |
| Wire stripper and side cutter | 0 | 20.00 | Reichelt |
Total, bench + bed €1,345.76
Rendered from hardware/shopping/solo-starter.toml. Found a cheaper or better part, or a dead link? Open a part substitution issue or a pull request. Next: the build guide.