Alde Heating and Water System
Bailey Unicorn Valencia

Water system on our Bailey Unicorn Valencia
Note: you do not need to have water in the hot water system
to use the Heating.
But, you do have to have the Mains Switch on to use the electric heating.
Alde Hot Water/Heating System
| The Alde system comprises of a Boiler that heats the
fresh water to feed the hot water system and the heating system fluid
that is circulated by a 12v pump round the caravan in a continuous
circuit that returns to the Boiler. The Fluid passes through a series of
Radiators and at some point rises to a Header Tank where you can see the
level and top up if necessary. The fluid is a mixture of 60% water and
40% ethylene glycol antifreeze. This needs to be replaced every 2 years.
Alde UK use Comma Super Coldmaster Concentrated Antifreeze with 2 year
Longlife protection. One of the main problems that people get with the system is air trapped at various points in the fluid circuit. On the Unicorn that I have there are supposed to be 5 bleed points dotted round the system. The only obvious one is the one on the top of the bathroom radiator and as this is a high point in the system will trap most of the air and should be checked on a regular basis. The Dealer should have ensured that the system is air free as they have a special purge tool to ensure this. |

Alde Control Panel

| 1 |
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Internal temperature setting (adjust up/down) |
| 2 |
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Boost Hot Water (On/Off) If selected, switches off automatically after 30min. |
| 3 |
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Gas (On/Off) |
| 4 |
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Mains Electric Setting 1, 2, or 3Kw (select value) |
| 5 |
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12v Pump running indicator (only illuminated when Pump running) |
| 6 |
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Mains feed to Boiler ON (only illuminated when power feed to Boiler is on) |
| A B | Moves the selected control left or right. Symbol flashes when selected | |
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Boiler ON/Off selection (On indication needs to be illuminated to switch the system ON for water and or heating) | |
| Hot water no heating needed | ||
A lot of people find it difficult to set the system to heat the water when the heating is not needed. These are the steps required to get hot water if you are on an electric hook-up ie mains. A/ on the control panel select the system to ON
B/ Set the Internal Temperature setting lower than the ambient
temperature (I set mine to 10C) this stops the pump running and hence no
heating is provided.C/ Select the Mains Electric Setting to suit the supply (on a
Site with a 16A supply I set mine to 3(kW))D/ Turn on the mains switch to the system (on my Unicorn it is over near the kitchen tap) You can confirm the mains is on to the system when you see the symbol
illuminated on the control panel.The water will now heat up. Part of the confusion is the Hot Water Boost setting When this is selected (ie
first illuminated) it increases the boiler temperature for 30 min to
boost the amount of hot water available for say showers by providing the
hot water at a higher temperature. |
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| Typical Radiator | Towel Rail, note the water does
not flow through it, it heats by convection. Note bleed valve on the top |
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| Boiler | Boiler mounted 12v Circulation Pump |
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| Header Tank | Header Tank Cover |
| I am often asked what I think of the Alde system in
comparison to the Truma fire with blown air distribution. I had the
blown air system with most of my previous vans and had found the best
settings and way to use it. But, we always had problems on our fixed bed
layout Bailey Caravans with getting the front air outlets to produce
warm yet alone hot air. The main problem being the long route of the
ducting with quite a length outside under the van. We insulated the
external pipe work which helped but did not cure the problem. The
heating system always kept the van at a good temperature but it wasn't
fully 'comfortable' and needed a bit of manual intervention on the
settings to keep it stable. The separate hot water system was fine. When we changed our van to one with the Alde heating/water system, this is what we found: a) The van seemed to take longer to heat up, but this was deceptive, as the whole fabric was warming, not just the air as it was with the Truma fire and blown air system. b) When the required temperature was reached, as set on the control panel, it just stayed there with no intervention. c) The whole van was warm and it was very 'comfortable' with no cold spots. d) Being able to set the clock and system to automatically set a different overnight temperature between set times was a major advantage and meant getting up to a warm van without overheating whilst sleeping. e) The boost water temperature setting gave us plenty of hot water for showering in the van. f) The lack of the fire gave us more useable space and a better layout in the van. |
Alde heating as explained on a Bailey Unicorn
click on photos for larger image
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| 2 x 3.15A
5x20mm Fuses F-type fuse, fast blow |
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| 12v Pump set to speed 2 as recommended | ||
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