Underslung LPG Tank 30 l, Ø 270 mm, GZWM, with Valves and Valve Box - Vapour Take-off for Motorhomes and Caravans
- Cylindrical 30 l LPG tank, 270 mm in diameter, for mounting under the floor of a motorhome, caravan or food truck. Comes with valves, valve box and U-brackets, has R67 approval and supplies heating, cooker and fridge.
This tank replaces the gas bottles you carry in the locker. It is mounted permanently under the floor of a motorhome, caravan, food truck or van conversion, and gas is drawn from it in vapour form, just like from a bottle. Type ZC 270/30 P holds 30 l, is 270 mm in diameter and about 605 mm long. It is filled to 80%, which is about 24 l of gas. The tank is made by the Polish manufacturer GZWM, is approved under UN ECE Regulation No. 67 and is supplied with valves fitted, a valve box and two U-shaped brackets.

Key features
- capacity 30 l, filled to 80%, which is about 24 l of LPG
- diameter 270 mm, length about 605 mm according to the manufacturer
- fill valve with 80% stop
- pressure relief valve opening above 27 bar
- float level gauge with dial and sender output for a remote gauge
- valve box and 2 U-brackets with bolts included
- E20 approval under UN ECE Regulation No. 67, class 1

Valves and fittings
- Fill valve with 80% stop. A float closes the inlet at 80% of capacity, leaving room above the liquid for the gas to expand as the temperature rises. 3/8" NPT female thread, with the included 3/4" UNF (JIC) elbow.
- Manual outlet valve with 1/4" NPT thread and W21.8 LH adapter. It draws gas from the space above the liquid, so your appliances get vapour, not liquid LPG.
- The pressure relief valve opens when the pressure exceeds 27 bar and protects the tank from overheating, for example in full sun.
- The float level gauge with dial shows how much gas is left, and its resistive sender output lets you connect a remote gauge in the cab.

Valve box and mounting
The valves sit in a four-hole valve plate welded to the tank. A box over them protects the valves from water, mud, road salt and stone chips. The tank is made of P310NB steel with a 2.1 mm wall and is fixed to the chassis on two U-brackets, supplied with bolts and washers. It is mounted horizontally, with the valves set according to the mounting mark on the tank.
Filling and installation
- The tank is filled at autogas stations through an external filling point in the side wall or sill, connected to the fill valve with an LPG hose. Filling point, hose and adapters are not included.
- The 80% stop ends filling automatically.
- Choose a place away from the exhaust and moving suspension parts, with access to the valve box.
- A regulator or a hose to the existing gas installation is connected to the outlet valve.
- Have a qualified gas technician check for leaks and approve the installation.
Intended use
The tank stores liquefied LPG and delivers it as vapour, so it supplies the appliances in the habitation area: heating, cooker, absorption fridge, barbecue or water heater.
Size overview
| Type | Diameter [mm] | Capacity [l] | 80% filling [l] | Length [mm] | Weight [kg] |
|---|---|---|---|---|---|
| ZC 200/16 P | 200 | 16 | 12.8 | 585 | 11.4 |
| ZC 200/20 P | 200 | 20 | 16 | 720 | 12.2 |
| ZC 200/25 P | 200 | 25 | 20 | 890 | 14.2 |
| ZC 200/30 P | 200 | 30 | 24 | 1070 | 16.2 |
| ZC 230/23 P | 230 | 23 | 18.4 | 630 | 12.4 |
| ZC 230/30 P | 230 | 30 | 24 | 809 | 14.9 |
| ZC 230/40 P | 230 | 40 | 32 | 1014 | 17.6 |
| ZC 270/30 P (this item) | 270 | 30 | 24 | 605 | 14.6 |
| ZC 270/40 P | 270 | 40 | 32 | 785 | 17.2 |
| ZC 270/55 P | 270 | 55 | 44 | 1060 | 21.7 |
| ZC 300/40 P | 300 | 40 | 32 | 647 | 17.2 |
| ZC 300/60 P | 300 | 60 | 48 | 935 | 21.8 |
| ZC 300/70 P | 300 | 70 | 56 | 1085 | 23.4 |
| ZC 315/60 P | 315 | 60 | 48 | 870 | 24.5 |
| ZC 315/70 P | 315 | 70 | 56 | 1000 | 28.4 |
| ZC 360/55 P | 360 | 55 | 44 | 629 | 24.9 |
| ZC 360/85 P | 360 | 85 | 68 | 936 | 33 |
| ZC 360/100 P | 360 | 100 | 80 | 1087 | 36 |
| ZC 360/120 P | 360 | 120 | 96 | 1298 | 40.2 |
Manufacturer data, weight of the bare tank.
Technical data
| Feature | Value |
|---|---|
| Type | ZC 270/30 P, cylindrical tank with valve plate |
| Capacity | 30 l |
| Permitted filling (80%) | 24 l of LPG |
| Diameter | 270 mm |
| Length | about 605 mm according to the manufacturer |
| Weight of the bare tank according to the manufacturer | 14.6 kg |
| Material | P310NB steel, wall thickness 2.1 mm |
| Test / burst pressure | 3.0 MPa (30 bar) / min. 6.75 MPa |
| Fill valve | 80% stop, 3/8" NPT, 3/4" UNF (JIC) elbow |
| Outlet valve | manual, 1/4" NPT, W21.8 LH adapter |
| Approval | E20 67R-01 0609, UN ECE Regulation No. 67, class 1 |
| Included | tank with valves, valve box, 2 U-brackets with bolts |
Questions and answers
How much gas does the tank hold?
The tank has a capacity of 30 l, and the 80% valve stops filling at about 24 l of LPG.
Can I fill it at an autogas station?
Yes, through an external filling point connected to the fill valve. The filling point and hose are sold separately.
Which appliances can this tank supply?
Gas appliances in the habitation area that use vapour: heating, cooker, fridge, barbecue or water heater, via a pressure regulator.
Which size should I choose?
For the same capacity, a tank with a larger diameter is shorter. Measure the space between the chassis members and compare it with the table above.
Manufacturer
Grodkowskie Zakłady Wyrobów Metalowych S.A., ul. Wrocławska 59, 49-200 Grodków, Poland.











