Eberspacher Hydronic

[larryjc]

My Eberspacher works fine although after about an hour fifteen it seems to need to relight itself - starts ticking and then there is a 'whoosh' as on initial start up.  However I wondered if they are hard to service.  The manual says clean the glow plug pin every year and get a dealer to decoke every 2000 hours - (but I can't find an hours counter in the control unit).  Do I really need a dealer or can an average mechanic (me) tackle it.  If it needs a dealer any recommendations?  We are in Lyme view on the Macc.  Thanks in advance.

[J R ALSOP]

Phone Nic at TWMarine Furness Vale 01663745757

[PeterF]

Has it got the circulating water up to the internal thermostat setting after that period, shutting down the firing until the circulating water cools down, and then needs to relight.

[NMEA]

47 minutes ago, PeterF said:

Has it got the circulating water up to the internal thermostat setting after that period, shutting down the firing until the circulating water cools down, and then needs to relight.

What he said, this is the usual behaviour of a unit that has insufficient radiator load due to poor initial system design and is the prime reason these things cycle like this and coke up prematurely.

Edited December 9, 2017 by NMEA

[larryjc]

14 hours ago, NMEA said:

What he said, this is the usual behaviour of a unit that has insufficient radiator load due to poor initial system design and is the prime reason these things cycle like this and coke up prematurely.

Interesting as it only has two radiators to supply and the hot water tank so might well be why it does it but I ususally only run it for an hour and then its not a problem.

[PeterF]

Sounds like it is working fine. After one hour the hot water tank will be up to temperature and the heat demand will reduce, so the circulating water gets hotter and the unit shuts down so it does not over heat. I have four radiators plus hot water on mine, but the boat fitter put thermostatic valves on three of the radiators, if I use them to control the room temperature, the Hydronic shuts down after 90 minutes.

[Sea Dog]

5 hours ago, larryjc said:

Interesting as it only has two radiators to supply and the hot water tank so might well be why it does it but I ususally only run it for an hour and then its not a problem.

I suggest you keep doing the 1 hour at a time thing. Get the boat warm quickly then let the stove keep it toasty.  Read the manual to make sure the flow through your calorifier circuit is properly balanced - too little flow will mean hot water takes too long, too much flow will cause short cycling. It's pretty easy to add additional rads which will also help. Make it work hard and it'll thank you for it.

[larryjc]

Thanks for all the replies.  However what I was really wanting to know is, is it difficult to decoke/service or should I get it done by a dealer.  And is there an hours counter hiddenin the software somewhere - cos I can't find one.

[NMEA]

Yes there is an hour counter in the software.

7 hours ago, PeterF said:

Sounds like it is working fine. After one hour the hot water tank will be up to temperature and the heat demand will reduce, so the circulating water gets hotter and the unit shuts down so it does not over heat. I have four radiators plus hot water on mine, but the boat fitter put thermostatic valves on three of the radiators, if I use them to control the room temperature, the Hydronic shuts down after 90 minutes.

Your boat fitter, like most boat fitters is clueless Revs are a no no on evaporator heaters.

[NMEA]

8 hours ago, larryjc said:

Interesting as it only has two radiators to supply and the hot water tank so might well be why it does it but I ususally only run it for an hour and then its not a problem.

I Despair.

[larryjc]

14 hours ago, NMEA said:

I Despair.

Why?

[NMEA]

Because so many installs are inapropriate for the boilers, and its usually the boilers that get blamed for any resulting faults.

 

[larryjc]

Sorry - are you saying that a Hydronic feeding two radiators and a hot water tank is not a good idea?  Its been working for several years before we bought the boat and works fine for us with the one minor query I had about it seeming to 'rest' after a while, which doesn't actually seem to be a problem as such.  I certainly wasn't blaming the boiler for anything merely asking how to service it.

 

[NMEA]

Thats exactly what I'm saying, the optimum is around the output of the heater in rads and ignore the calorifier, the calorifier rips therms from the coolant when cold but as the potable water temperature rises it takes less and less and then almost nothing. The rads tend to take a fairly constant level, (unless the air temperature rises to 70+ decrees C  ) It will of course work, but not optimally and will coke up faster. Servicing is not the same as a decoke, a decoke is pretty straight forward and I can send you a manual if you PM me an email address. Servicing requirers an exhaust gas analyser, pressure tester, software, pump calibration equipment and a test tank with RdLyme to remove internal scaling.

[Sea Dog]

4 hours ago, larryjc said:

Sorry - are you saying that a Hydronic feeding two radiators and a hot water tank is not a good idea?  Its been working for several years before we bought the boat and works fine for us with the one minor query I had about it seeming to 'rest' after a while, which doesn't actually seem to be a problem as such.  I certainly wasn't blaming the boiler for anything merely asking how to service it.

 

Larry, trust NMEA's advice here - he's generous both with sage advice and with documentary support. It's when they are allowed to 'rest' as you put it that they can begin to have snags and a short life. Many such failures in narrowboat installations attracted bad press for Eberspacher, so much so they did an investigation and produced a report of their findings. In a nutshell, they put the failures down to low load running either because of inappropriate installs and/or users treating them as they would a gas central heating system at home, which they are not. The use of a room thermostat encourages cutting in and out for short periods of low loading - hence why my roomstat is set at 'max' and stays there. If you visit the Eberspacher website you can find a copy of their report which is worth a read.

[larryjc]

Thanks everyone - very much listening to advice. My rads are on max and I've been looking into my installation which really needs another radiator.  Sounds like yet another task for the spring.