Underslung LPG Tank 100 l, Ø 360 mm, GZWM, with Valves and Valve Box - Vapour Take-off for Motorhomes and Caravans
- Cylindrical 100 l LPG tank, 360 mm in diameter, for mounting under the floor of a motorhome, caravan or food truck. Comes with valves, valve box and U-brackets and supplies vapour to 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. The tank holds 100 l, is 360 mm in diameter and about 1087 mm long. It is filled to 80%, which is about 80 l of gas, roughly what almost four 11 kg steel bottles hold. The ZC 360/100 P tank is made by the Polish manufacturer GZWM in Grodków. It is built to class 1 under UN ECE Regulation No. 67 and supplied with valves fitted, a valve box and two U-shaped brackets.

Key features
- capacity 100 l, filled to 80%, which is about 80 l of LPG
- diameter 360 mm, length about 1087 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
- P310NB steel, wall 2.8 mm, class 1 under UN ECE Regulation No. 67

Valves and fittings
- Fill valve with 80% stop. A float closes the gas inlet when the tank reaches 80% of its capacity, so there is always room above the liquid for the gas to expand as the temperature rises. The connection has a 3/8" NPT female thread, and with the supplied elbow 3/4" UNF (JIC).
- Manual gas outlet valve with 1/4" NPT thread and W21.8 LH adapter. It draws gas from the space above the liquid, so your appliances receive vapour, not liquid LPG.
- The pressure relief valve opens when the pressure in the tank exceeds 27 bar and protects the tank from overheating, for example in strong sunshine.
- The float level gauge with dial shows how much gas is in the tank. It also has a resistive sender output for a remote gauge in the cab or on the control panel.

Valve box and mounting
All valves sit in a valve plate welded to the tank. A box fitted over them protects the valves from water, mud, road salt and stone chips. The tank is fixed to the vehicle chassis on two U-shaped brackets, supplied together with bolts and washers. The tank is mounted horizontally, with the valve box accessible from the side you will operate it from.
Filling the tank
The tank is filled at autogas stations through an external filling point fitted in the side wall or sill of the vehicle. The filling point is connected to the fill valve with an LPG hose. The filling point, hose and filling adapters for different countries are not included and are chosen to suit your installation. The 80% stop ends filling automatically, so you do not have to watch the pump display.
Space and installation
- Measure the free space under the floor: the tank is 360 mm in diameter and about 1087 mm long, and a safe ground clearance must remain below it.
- Choose a place away from the exhaust and moving suspension parts, with access to the valve box.
- Bolt the U-brackets to the chassis, lay the tank in them horizontally and run the hose from the fill valve to the external filling point.
- Connect a regulator or a hose leading to the existing gas installation 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 | 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 (this item) | 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 |
|---|---|
| Manufacturer | GZWM |
| Type | ZC 360/100 P, cylindrical tank with valve plate, vapour take-off |
| Capacity | 100 l |
| Permitted filling (80%) | 80 l of LPG |
| Diameter | 360 mm |
| Length | about 1087 mm according to the manufacturer |
| Weight of the bare tank according to the manufacturer | 36 kg |
| Material | P310NB steel, wall thickness 2.8 mm |
| Test pressure | 3.0 MPa (30 bar) |
| Burst pressure | min. 6.75 MPa |
| Fill valve | 80% stop, 3/8" NPT female thread, with 3/4" UNF (JIC) elbow |
| Outlet valve | manual, 1/4" NPT, with W21.8 LH adapter |
| Pressure relief valve | opens above 27 bar |
| Level gauge | float type with dial, sender output for a remote gauge |
| Construction | class 1, UN ECE Regulation No. 67 |
| Use | heating, cooker, fridge and other gas appliances in the habitation area |
| Included | tank with valves, valve box, 2 U-brackets with bolts and washers |
Questions and answers
How much gas does the tank hold?
The tank has a capacity of 100 l, and the 80% valve stops filling at about 80 l of LPG. That is roughly what almost four 11 kg steel bottles hold.
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, absorption fridge, barbecue or water heater. A pressure regulator is fitted between the tank and the appliances.
Can I connect a level gauge in the cab?
Yes. The gauge has a resistive sender output for a remote gauge or a control panel that supports this type of sensor.
Manufacturer
Grodkowskie Zakłady Wyrobów Metalowych S.A., ul. Wrocławska 59, 49-200 Grodków, Poland.











