Alde Comfort 2920
Official technical documentation and workshop diagnostics for Comfort 2920.
Technical Specifications
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|
N/A | Boiler does not start or operate Possible Cause: Interruption in electrical power supply or gas supply | Check the 12V supply line, inspect the fuses, and verify gas supply. If the issue remains unresolved, contact an authorised service centre. | DIY Check / Tech Fallback |
Frequently Asked Questions
Q: Why is my hot water luke warm after a service?
During service the technician might have left your circulation pump on continuous mode. This mode is used for testing purposes but will deprive the hot water cylinder of heat. Probably best to reset your Alde control panel to restore factory default settings. Refer to the operating instructions .
Q: Why is my Alde heating gurgling after a service?
During service the technician might have left your circulation pump on speed 5 to purge air. Set it back to speed 2 – 3 for touring caravans and B and C-class motorhomes, or just under speed 4 for A-class motorhomes. If the heating fluid was changed there may be air in your Alde system. Refer to the operating instructions .
Q: In winter, can I use my central heating even though the fresh water is drained down?
Yes, use your Alde system completely as normal. No harm will result, there are no heating elements in the hot water cylinder to burn out.
Q: What antifreeze products are Alde approved?
In the UK, they conform to Alde Approval 40X0 2024 : Alde Protective Premium G12++ and G12evo Fuchs Fricofin DP Comma Xstream G40 Volkswagen Group G12evo (Our G13 products were discontinued at the end of 2023.) These products are available ready-mixed with deionised water. Always read the label. All are intermixable, magenta in colour, providing frost protection to -37 °C and 5 year corrosion protection. There is a different list of Alde-approved antifreeze products in North America with a completely different chemical base.
Q: What fluid do I top-up my Alde heating system with?
Use the same antifreeze product as is currently in the system. If your heating fluid is magenta in colour, it’s very likely your system is filled with an Alde-approved antifreeze . So top-up with an approved product, they’re all intermixable. If it is not magenta in colour it is safest to top-up with a cupful or two of deionised water. You will have slightly less protection from frost, corrosion and bacteria, but damage caused by mixing incompatible antifreeze is the bigger risk. Then change the heating fluid as soon as practicable, using an Alde-approved antifreeze product.
Q: How do I get the most efficiency from my Alde heating system?
Always enable the maximum electric and gas/diesel heating available. This reduces energy consumption. Don’t “whack up” the desired room temperature high if you’re cold. Always set it to a comfortable room temperature otherwise you’ll waste energy (getting too warm and having to open windows). Comfortable room temperature shouldn’t be shorts and t-shirt temperature. Wear a gillet or cardie and set the room temperature a couple of degrees lower to save energy. If you don’t use hot water at night, set the system to ignore hot water demand and save energy. Seasonally bleed air from the heating fluid and always ensure vents in cabinetry are unobstructed top and bottom. This reduces energy consumption.
Q: How much electrical current does the Alde heating draw?
From 12 VDC The system is very dynamic, so the draw from the leisure battery fluctuates a lot. It peaks during ignition, around 2 A for gas heating. Around 20 A for diesel heating. For off-grid planning, assume gas heating will draw around 1 A from the leisure battery whilst active, diesel heating around 4 A. When the system is shutdown, parasitic drain is around 80 mA. From 230 VAC Although mains electricity in the UK is nominally 230 V, in reality its median is more like 240 V. That’s roughly: 1 kW = 4.8 A 2 kW = 9.5 A 3 kW = 14.3 A
Q: How quickly should my vehicle heat up?
It depends on the design and insulation of the vehicle, how cold it is outdoors and of course, how much power you have available. Power is heat. These days most vehicle manufacturers aim for about an hour to reach comfortable room temperature from a cold start.
Q: Can I leave my Alde heating on a frost protect setting?
You can heat your vehicle over the winter but if you aren’t staying in it, is it worth the cost? It’s your choice though. Hooked up to mains electric on the driveway, you could set the desired room temperature to 10 °C and 2 kW electric heating. Regularly check the interior for condensation and rodent infestation, and note that it’s likely some compartments won’t be frost protected.
Q: What general maintenance and consumables are there?
The heating fluid in your Alde heating system is consumable and it needs replacing when its corrosion protection expires. Alde-approved antifreeze products are magenta in colour and have a 5-year life. Bleeding air from the heating fluid occasionally will improve efficiency. Seasonally inspect the boiler’s flue. The hose should be secured, undamaged, and terminal clear of obstructions. If staying in the vehicle for 10 or more days, remember to replenish the air cushion in the boiler. Remember to drain the fresh water before freezing weather sets in. When draining, ensure the red breather valve isn’t scaled up. Refer to the operating instructions for your heating system. The law may require your vehicle has an annual service, especially if used as an annex to a permanent dwelling, for hire, or as a workplace.
Q: How do I programme Day and Night Mode?
Imagine a 24-hour clock face and it’s much easier than you think.
Q: In summer, how do I get hot water without central heating?
Simply set the desired room temperature to about 15 °C on the control panel. This is low enough to prevent the central heating from circulating most hours of the day and night in the summer. Hot water is unaffected.
Q: What heating fluid is in my Alde system?
The installer decides what fluid your Alde system is originally filled with. Preferably Alde-approved antifreeze , which is magenta in colour. We don’t recommend using any non-approved antifreeze products.
Q: What level should the fluid be in the expansion tank?
About 1 cm above the Min mark when cool. (Then, when the fluid’s heated it will expand up towards the Max mark.)
Q: How much fluid is in the central heating?
As a rough guide, touring caravans, B-class and C-class motorhomes hold 10–15 litres, A-class motorhomes and boats hold 20–25 litres.
Q: What is the air cushion reminder?
After 10 days of use, the Alde heating system will remind you to replenish the air cushion in your hot water cylinder. This ensures smooth running. If you’ve had water in the system during this time, here are the steps to replenish the air cushion: Switch of your water pump. Open taps and shower fully. Open safety drain valve, draining water for 5–10 seconds before shutting again. Recharge the water system as normal. If you don’t have any water in your system, you can ignore the reminder.
Q: Why is my hot water scalding?
Regulations require stored hot water to be heated to scalding temperature to prevent the growth of legionella, a deadly bacteria. The Alde TMV3 is an aftermarket accessory that restricts the temperature of hot water supplied to the outlets.
Q: How much hot water does the Alde system produce?
A continuous shower of about 4–5 minutes every half-hour is normal. The Alde TMV3 is an aftermarket accessory that can reduce hot water wastage in the shower. The Alde Flow provides continuous hot water and can be fitted to any Alde-equipped vehicle from 2018 model year onwards. Available exclusively for retrofit in the UK at Moosewerks .
Q: Can I use any fresh water in my Alde system?
Only use palatable drinking water. Sites in Iberia and the Maghreb may supply water with high levels of bleach or salt that will corrode stainless steel. A supply may be marked as drinking water but if you can’t stomach it, don’t use it in the Alde system unless your vehicle is equipped with at least a 4-stage RO water filter.
Q: What sterilizer and descaler should I use in my Alde system?
Any that are suitable for use with a stainless steel hot water cylinder. Always read the label. Clean Tabs have a range of suitable and widely available products.
Q: In winter, do I need to drain my fresh water?
Yes. Although it’s possible to design a self-winterising vehicle, the vast majority of vehicles on the market aren’t.
Q: Can I use gas/diesel and electric heating at the same time?
Yes, please do. The system can also be set to prioritise either gas/diesel or electric if one is cheaper than the other, for example.
Q: How much gas does the Alde heating consume?
As a rough guide, when heating with gas a 6 kg propane bottle should last all weekend. Expect considerably different performance if camping in freezing weather.
Q: What type of LPG should I use, propane or butane?
Propane. Butane isn’t suitable for use in temperatures below 13 °C (BS 5482 Part 1).
Q: Can I use Autogas?
Yes.
Q: Can I use my gas heating as I'm driving along?
We don’t recommend it. Even with a crash sensor fitted to the bulkhead regulator, if you pull into a fuel station with gas heating enabled fumes could be sucked directly into the combustion chamber. It would be no different to standing on the forecourt with a lit camping stove. You’d have to remember to pull over and disable gas heating first. The one time you forgot could be the last.
Q: What if I accidentally fill with B10 diesel whilst on the Continent?
Don’t panic, no harm will result in the short-term. (B10 and higher concentrations of biodiesel will reduce the lifespan of the burner in long-term use.) So, use your diesel heating as normal until you can refill with half a tank of compatible fuel. Try to avoid making the same mistake twice.
Q: What type of diesel fuels can I use?
Alde Compact 4000 D and 4000 D are compatible with B7 diesel (conforming to EN 590) and XTL diesel (conforming to EN 15940). For anyone using agricultural or marine diesel, HVO conforming to EN 15940 is also compatible.
Q: Can I use my diesel heating as I'm driving along?
We don’t recommend it. Although technically feasible, if you ever forget to disable diesel heating before pulling into a fuel station you might upset other customers and the staff. Worse could happen if fumes are sucked directly into the combustion chamber. Consider having an Alde engine heat exchanger fitted instead.
Q: Can I convert my Alde heating system from gas to diesel fuel?
It all depends on how much rework of the boiler compartment and diesel fuel tank is involved. Alde Compact 4000 D is not a drop-in replacement for Alde Compact 3030, for example, and not all diesel fuel tanks have accessible senders or spare fuel pick-ups. You may find it’s cost prohibitive. Such a project would probably cost upwards of £5K.
Q: Can Alde provide diesel heating?
Yes. Alde Compact 4000 D and 4000 D Plus are both diesel fuel heating systems. Alde Compact 3030 and 3030 Plus cannot provide dedicated diesel heating, but an Alde-equipped motor vehicle can be fitted with the engine heat exchanger to utilise waste heat from the engine.
Q: Can I use underfloor heating only to heat my vehicle?
No. Even vehicles achieving the highest BS EN 1645 grade are not as well insulated as buildings. For only underfloor heating to sufficiently heat a vehicle the floor would be too hot to walk on.
Q: Where can I buy Alde products?
We supply many of the UK leisure industry’s online retailers and wholesalers . But if you’re a vehicle manufacturer producing at least 50 units a year, please contact us to discuss a strategic partnership.
Q: Is the central heating pressurised like a car radiator?
No, the central heating is open vented. This reduces weight, and draw from the leisure battery.
Q: Can I use electric heating from the leisure battery only?
No. The Alde heating system requires 12 VDC power for its controls but 230 VAC power for electric heating. If you’re off-grid you’ll need gas or diesel heating. If you tried powering the electric heating from a leisure battery it would generate about 9 W of heat. That’s about a tenth of the heating your own body provides.
Q: How much does Alde heating weigh compared to forced/blown air heating?
About 10 kg heavier filled, when compared to a combi heater. These days separate space heaters and water heaters tend to be less powerful so aren’t really comparable.
Q: Which caravan and motorhome manufacturers currently fit Alde heating?
Our customers as of current model year.
Q: Can I use copper parts in the central heating with the Alde system?
No. Alde Compact boilers contain aluminium surfaces in the glycol cylinder. Any particles from copper parts that circulated into the boiler would cause galvanic corrosion.