Truma Ultraheat and S3002 Spares: How to Identify Your Heater

Truma S-Series Identification

A practical guide from Bedam Leisure — caravan & motorhome specialists

Every order for Truma Ultraheat and S3002 spares comes down to one question: which heater have you actually got? The model number is on the data plate behind the drop-down front panel, and the Ultraheat is not a heater at all — it is the 230V electric element fitted behind the gas fire, with its own part numbers.

Get those two facts straight and ordering is simple. Get them wrong and you end up with an ignitor that will not fit or an element for a heater you do not have. We sell these parts every week, and the returns almost always come from the same mistake: ordering for an S3004 when the van has an S3002, or buying a gas part when the fault is on the electric side. Here is how to tell, in five minutes, with a torch — everything mentioned is in our Truma Ultraheat and S3002–S5004 spares range.

1 Find it

Where the plate is and what it tells you

Pull the drop-down front panel off the fire. On most installations it unclips or lifts off its lugs without tools, and behind it, on the heater body, is a data plate with the model, the gas category and a serial number. That plate is the only thing worth trusting. The van's make and year will not tell you, because the same caravan model was built with different heaters across a production run, and plenty of these fires have been swapped over thirty years of service.

Read the model as two parts. The first digit is the output band: a 3002 or 3004 is roughly a 3.4kW fire, a 5002 or 5004 roughly 5.5kW. The last two digits are the generation, and that is what decides which spares fit. Write the whole number and the serial down, and photograph the plate while you are down there — you will need it again.

2 Generation

S3002/S5002 or S3004/S5004: the split that matters

This is the one distinction that causes most wrong orders, and you can usually make it without the plate at all, because the two generations light the fire in completely different ways.

The earlier S3002 and S5002 use manual piezo ignition. You hold the gas knob in and press a separate button, and you get one mechanical click and one spark per press. There is no battery anywhere in the system. If that is what you are doing on a cold morning, your ignition parts are the piezo ignitor kit and the spark electrode that it fires.

The later S3004 and S5004 have automatic ignition. You turn the knob and the heater ticks away by itself, repeatedly, from a battery — in most installations a single cell tucked behind the front panel. If yours ticks on its own, it is an auto ignitor you need, and a piezo kit will not go anywhere near it.

Before you order any ignitor: change the battery and clean the electrode tip. A sooted or cracked electrode gives a weak spark that lights on the fifth go in September and not at all in January, and that symptom gets blamed on the ignitor far more often than it deserves.

There is a third ignition symptom worth knowing, because it points somewhere else entirely. If the fire lights perfectly while you hold the knob in and then dies a few seconds after you let go, the spark is fine and the flame-failure device is not holding the valve open. That is the thermocouple: a slim probe sitting in the flame, which tells the gas valve there is something burning. They go lazy with age and soot, and it is a common and inexpensive repair.

Lights, then goes out? That is the Truma thermocouple (30050-13900) at £65.99, not an ignition part. The same symptom on a different Truma appliance is covered in our Combi fault-finding guide.

3 Electric

Have you got an Ultraheat behind the fire?

This is where the vocabulary trips people up. The Ultraheat is not a heater you can buy instead of an S-series fire. It is a 230V electric element that mounts behind the gas fire so the van can be heated on mains hook-up without burning gas, usually switchable in steps up to around 2kW. The same fire can have one or not have one, which is why "I've got an Ultraheat" does not tell us which gas parts you need, and "I've got an S3004" does not tell us whether you have the electric side at all.

Telling is easy. If there is a switch panel near the fire with wattage settings on it, rather than just the gas knob, you have the electric side: the control is normally a TN-series 230V panel, and the element and its PC board live behind the fire. A heater that runs perfectly on gas but does nothing on hook-up has a fault on this side only, and it is usually the board or the element.

Element or board? An element failed open circuit simply does nothing. One failed to earth trips the RCD the moment you select electric. Elements for the older Ultraheat are getting scarce, so if yours has gone, send us the plate details and we will tell you what is still available before you commit to a repair.

4 Blown air

TEB or TN: have you got blown air?

An S-series fire on its own is a convector: it warms the air around it and lets it circulate. Many installations add a fan kit that pushes warm air through ducting to outlets elsewhere in the van, and the fan is a separate system with separate part numbers again.

There are two families. A TEB fan runs on 12V, so it works off the leisure battery while you are touring. A TN fan runs on 230V and only works on hook-up. Each has its own control panel, and panels are not interchangeable between them — a TN panel on a TEB fan is a dead panel. Look at how yours is switched and labelled, or trace the cable: 12V to the consumer unit means TEB, mains means TN.

5 Order

Matching the rest of the parts to the plate

With the model, the generation and the options known, the rest divides neatly. Ignition, burner and valve parts go by generation; electric parts by Ultraheat; fan and panel parts by TEB or TN. The outside of the system — flue, roof cowl and cowl top — goes by what is physically on your roof, which you can see and measure rather than guess.

The cosmetic and handling parts are the cheap end, and the ones worth doing while the panel is already off. Mica windows go cloudy and crack, fire tops get knocked, knobs and knob sockets wear until the detents stop catching. None of it changes how the fire burns, but a thirty-year-old fire with a clear window and a clean top looks like one somebody has looked after.

Two worth adding to any order: a small mica window (30030-42700) at £31.99 if yours is cloudy or cracked, and a Truma roof cowl (30010-20900) at £20.99 if the one on the roof is chalky, split or has had thirty winters of UV. A damaged cowl is a safety matter, not a cosmetic one.

Common questions

Where is the model number on a Truma S3002?

On the data plate on the heater body, behind the drop-down front panel. The panel normally unclips or lifts off without tools. Record the model and the serial, and photograph the plate — you will want it again for the next part you order.

Will S3004 parts fit an S3002?

Some will and many will not, so check rather than assume. Ignition is the clearest divide: the S3002 and S5002 use manual piezo ignition, the S3004 and S5004 use an automatic ignitor, and those parts are not interchangeable at all. Send us the plate details if you are unsure.

What is the difference between a Truma Ultraheat and an S-series heater?

The S-series is the gas fire. The Ultraheat is the 230V electric element fitted behind it so you can heat the van on mains hook-up. They are two separate systems sharing a space, with separate part numbers, and a fire can have the electric side or not.

My heater works on gas but not on electric. What is wrong?

That points at the Ultraheat side only. Check you are on hook-up with the RCD and breaker in and enough amps at the pitch, then suspect the Ultraheat PC board or the element — an element failing to earth trips the RCD the instant you select electric.

Can I fit these parts myself?

Knobs, knob sockets, mica windows, fire tops, control panels and cowl tops are reasonable owner jobs. Ignitors, electrodes, thermocouples and anything touching the burner, gas valve or pipework need a Gas Safe registered engineer with LPG and caravan or motorhome qualifications, and the 230V side needs a competent electrician.