Alde heating, Pump very noisy on startup

ClubMemberD00A4A73FE
ClubMemberD00A4A73FE Forum Participant Posts: 3
edited February 2016 in Motorhomes #1

Eldis, Aspire 205, registered 2015

When the van was new, the heating system started silently, over the ensuing time to current, the pump has got noisier and noisier during startup.  This extremely noisy period is now lasting about 4 minutes on full volume and then gradually tapers off as
if the pump is managing to reach some kind of flow or pressure.  However, the most recent development is for the noise to restart with gusto once the heating system reaches the set temperature.

The liquid level in the reservoir is at Max and all the bleed points I can find (3) in the circulation piping are liquid.  I haven't drained or vented the boiler.

The noise events occur both on 240v and 12v operation.

When I contacted the suppliers, Catterick Caravans, they were, to say the least unhelpful, and as we live in Aberdeen the round trip costs are prohibitive.

I'm sure I'm missing some simple step and I hope somebody has some clues where I'm going wrong.  Apologies if this subject has been covered before, I did search the archives but none of the posts seemed to cover my issues.

Comments

  • SteveL
    SteveL Club Member Posts: 12,310 ✭✭✭
    5,000 Likes 1000 Comments Name Dropper
    edited February 2016 #2

    However, the most recent development is for the noise to restart with gusto once the heating system reaches the set temperature.

    I am not sure what you mean by the above, as our heating pump shuts off when the set temperature is reached. Also the pump itself is 12 volt, or at least ours is, there is no 240 volt pump. Have you checked to see if anything has come  loose, or is touching
    it, that might be resulting in vibration. Sorry I can't be of more help, but ours has only ever made a slight whine, even when we have been chasing air out of the system.

  • jakeontour
    jakeontour Forum Participant Posts: 63
    edited February 2016 #3

    It definitely shouldn't be doing that!  You don't need to take the 'van to the supplying dealer as the Alde system has it's own warranty. 

    There are fixed and mobile Alde agents in Scotland, see http://www.alde.co.uk/service.php#scotland 

    Hope you get it sorted soon, it's a great system.

  • ocsid
    ocsid Forum Participant Posts: 1,395
    1000 Comments
    edited February 2016 #4

    Where is the pump located in your installation; I am expecting it to be close to the boiler or within the header?

    If the boiler then it probably has the variable speed setting type. If so is the speed set to number 2 or is it much higher (5?).  2 or 3 are typically the speeds needed to operate the system, speed 5 is for initial setting up and priming but during PDIs I read this is not always reset back to a lower level.

    If in the header, have you done the cap up too tight to either off set the rotor too close to the body or transmit too much noise.

    Are any pipes "leaning" against the furniture so making a noise short to a bit of structure that could act as a sounding board? They can usually be eased away. These will be more critical if local to the pump.

    If the pump is in the header, try a test with the header mounting screws eased off or removed; again hunting for possible noise shorts.

    On pump start up there will be more noise generated within the fluid until the fluid flow is established; this should not be marked but peceptable.

  • ClubMemberD00A4A73FE
    ClubMemberD00A4A73FE Forum Participant Posts: 3
    edited February 2016 #5

    Thanks for your replies, food for thought!

    The pump is located about 2m from the heater, in an exterior accessed storage box and the pump is mounted in the expansion tank.  I phoned our local Elddis supplier and in discussion it appears the fluid in the expansion tank should be kept just slightly
    above the minimum mark when cold.  I have topped up mine to the maximum mark.  Also when I did this top up I noticed the pump was screwed into the expansion tank quite loosely.

    Of course being of that age where you tightened things to tight and then added in that extra bit of torque for good measure, I'm pretty certain, that given a direct nuclear detonation the pump would be firmly fixed to the expansion tank!

    So given the benefit of hindsight, it now seems to point to a bit of a home goal, 1, overzealous filling and 2, brute strength!

    I'll experiment further and hopefully be able to close out this query!

     

  • ClubMemberD00A4A73FE
    ClubMemberD00A4A73FE Forum Participant Posts: 3
    edited February 2016 #6

    Success!  

    I did a bit of probing around (mirror, torch and thin stick) inside the expansion tank and it would seem the noise was the result of the pump impeller striking the bottom of the expansion tank.  The noise stopping after 5 mins
    or so was probably due to the impeller lifting clear as the temperature of the pumped fluid raised and this expanded the tank a little thereby lifting the impeller clear.

    This prognosis would also explain why the noise reoccured as the set temperature was achieved as the pumped liquid cooled and the expansion tank contracted.

    The solution was to insert a very thin spacer washer under the pump mating face and to not tighten the pump too tight.

    We are now back to silent running and I feel like I've just discovered Gravitational Waves.

    Thanks again for the pointers to the cure!

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