Fitting a Webasto

[Johny London]

Quick update. I've done the exhaust as best I can given the height of the outlet etc - it just needs lagging. All electrics hooked up and the fuel tank take off done - filled up with diesel to test it! No leaks so that's something.

I'm ready to flush out and commission. The manual said 25% glycol mix, I've not seen any reference to inhibitor or anything - aside from canals r us mentioning an inhibitor and anti freeze mix further up this page?

Fingers crossed it's running before the worst of the weather gets here.

[NB Lola]

Great progress, I am impressed.

[cuthound]

3 hours ago, Johny London said:

Quick update. I've done the exhaust as best I can given the height of the outlet etc - it just needs lagging. All electrics hooked up and the fuel tank take off done - filled up with diesel to test it! No leaks so that's something.

I'm ready to flush out and commission. The manual said 25% glycol mix, I've not seen any reference to inhibitor or anything - aside from canals r us mentioning an inhibitor and anti freeze mix further up this page?

Fingers crossed it's running before the worst of the weather gets here.

I changed my antifreeze from blue to a 25% solution of Ford 10 year Longlife, so that I don't have to worry about changing it for a while. That way you are covered against freezing and corrosion.

[Johny London]

Hmmm, so you can kinda put what you like in? Not sure whether I should be treating it like a car or a domestic system - after all the rads are domestic ones.

Anyway, I have flushed and commissioned - just a couple of drips at valves etc but all sorted now. I'll drain down a rad or two another day and put the mixture in once I'm confident.

Using the fill loop, I was only able to pressurise to just a little below 1 bar. I couldn't hear from the stern if the water pump was still running or not, but it's just about enough pressure I think.

Fired up the Webasto and it took a few goes as I have a fairly lengthy fuel run, but there is a sign of some warmth creeping into the rads as I write. Seems slow to heat up - is that normally the case? Wonder if it is stuck in low power mode. Obviously will need to go around and re bleed/re pressure etc but will do that tomorrow. Might be too much air trapped somewhere but it doesn't seem that warm at the pipes near the unit... yet.

Need to work out the capacity of my system so I can get the right amount of additive. I know one thing - one triple rad = one bucket of water

Just in time for the coming big freeze.

[Johny London]

Now the'yre cookin'

Anti freeze recommendations/costs please.

[NMEA]

Use Screwfix own brand inhibited central heating antifreeze. Their inhibitor is compatible so no need to drain down and replenish every two years as you can just add inhibitor to keep the corrosion protection going.

[gbclive]

42 minutes ago, NMEA said:

Use Screwfix own brand inhibited central heating antifreeze. Their inhibitor is compatible so no need to drain down and replenish every two years as you can just add inhibitor to keep the corrosion protection going.

I’ve heard this recommendation before but I’m not sure which products are being referred to.

Under Inhibitor / Protector, I can only see Fernox, Flomasta and Sentinal.

Sorry if I’m missing something here 

Thanks.

[NMEA]

Flomasta is the one, it's their cheaper range but nothing wrong with it at all.

[gbclive]

21 minutes ago, NMEA said:

Flomasta is the one, it's their cheaper range but nothing wrong with it at all.

Thanks NMEA 

[Johny London]

Yes, thanks for that ) I see the flomasta - 5l for £20. I'm not sure of my heating capacity (the rad information doesn't cover capacity) I'm guessing a couple of those for the average narrowboat system?

[NMEA]

12 hours ago, Johny London said:

Yes, thanks for that ) I see the flomasta - 5l for £20. I'm not sure of my heating capacity (the rad information doesn't cover capacity) I'm guessing a couple of those for the average narrowboat system?

I have yet to encounter an "average" system   don't forget that 5l of the stuff makes 20l of coolant at 25% concentration which is quite a lot, when installing new systems we also dilute with deionised water being the absolute pedants we are. As for calculating the coolant volume, this will help  https://inspectapedia.com/heat/Radiator_Volume_BTUs.php

[canals are us?]

I filled the system to get rid of any flux residues etc and drained it into bowls and poured into buckets bought  with litres marked inside to work out volume. Then I knew how much antifreeze/inhibitor to put in. Glad you got finished in time for the cold weather.

James

[David Mack]

On 24/02/2018 at 21:06, NMEA said:

Use Screwfix own brand inhibited central heating antifreeze. Their inhibitor is compatible so no need to drain down and replenish every two years as you can just add inhibitor to keep the corrosion protection going.

There's nothing in the product description that says that central heating inhibitor has antifreeze properties. Is it as good as a car antifreeze/inhibitor product?

Edited February 28, 2018 by David Mack

[NMEA]

On 23/09/2017 at 13:37, jddevel said:

I fitted my Webasto as a sealed system with no header tank with a feed including isolating valves and a removable feed hose as in a domestic combi from the domestic supply. However as was pointed out to me filling the system was going to be difficult that way to introduce anti-freeze PLUS and extremely important the possibility of contaminating the domestic supply with anti-freeze. A definite no no. So converted it to include a header tank.

A case perhaps of a little knowledge etc.

Introducing antifreeze and topping up to a sealed system is straight forward and filling loops have non return valves to ensure no back flow, do you really believe WRAS would appove such systems to the municiple domestic supply otherwise. As you rightly say, a ittle knowlege etc.

6 hours ago, David Mack said:

There's nothing in the product description that says that central heating inhibitor has antifreeze properties. Is it as good as a car antifreeze/inhibitor product?

Short answer is yes.

[Johny London]

Been keeping nice and warm thanks to the Webasto - and I got the inhibitor in too. I've been making sure not to leave the heater running too long - to avoid it going into low output mode and coking up. When it starts the pump ticks about twice a second, after about 90 mins or so it slows down (and all the rads seem up to temperature) so that is when I have been switching it off - is that correct or can it be left on till it is almost not ticking at all - just once it had gone very quiet.

Hopefully get a bit more life out of it than I do with batteries!

[NMEA]

The TTC has only two heat levels so your pump speed reduction indicates a reduction to half heat. Good news is the new Thermo EVO is now available, it is fully modulated just like the air heaters so should go a long way to stop this happening, only in 24v at the moment though.

[Johny London]

Thanks. In what way is that good news though? Unless they are gonna bring me round a free upgrade and install it! Oh and fit me a 24v system.

I wonder if I can devise a way to easily monitor the ttc? For example a flashing led to match the pump speed? Does the pump have a pulsed 12v sent to it or is it constant? If the former would be easy to add an indicator. I usually only run the heater when the engine is running because it flattens the batteries but I can't hear the ticking unless I turn the engine off!

PS - I thought htere would be just two pulse speeds but it seems to do gradually variable.

Edited March 19, 2018 by Johny London

[NMEA]

Good news for others fitting units in the future, if a TTC is flattening your batteries then I think you need to look at either your charging regime of battery bank, over a two hour period a TTC should use less than 3.5ah. 

[Johny London]

Yeh I know... don't get me started on batteries

[starman]

Thought I'd pull this thread up again as I'm fresh into Webasto ownership and it answers some - but not all - my questions.

The Unit is a Webasto Thermo 50 which was fitted by the previous owner and heated three rads - one gigantic double up front and two small ones - plus the hot water. All plumbed in 15mm, which appears to be the first mistake. It is un-pressurised with a big, 10 litre header tank.

I'm replacing and re-sizing the rads, replumbing the pipework and slightly re-siting the boiler itself.

Questions:

1. Would it be better to make it a pressurised system? If so, any advice?

2. If I go open vented, do I really need that 10 litre header?

3. I understand the need for a heat soak rad when I just want hot water . Would thermostatic rad valves elsewhere be the simplest way to switch out the rest of the heating?

4. In re-locating the boiler and pump am I right in thinking the present supply line cannot be altered?

 

 

[NMEA]

Do you mean a Pro 50 vehicle unit or a pro 50 water station, the Water station is the only one approved for marine use and available in 24v only? Personally I would go pressurised, we fit almost exclusively these days, never fit thermostatic valves as the induce the boiler to cycle, not a good thing, the best thing you can do is have a good read of the Webasto marine install manual, it will answer all your questions and some you may not even have thought of yet. If you drop an email to ecmhe@talktalk.net I will ping you back a copy.

[Johny London]

Obviously NMEA is the authority here, but to add what I can from my experiences...

The "spine" of the system should be in 25mm, and the pipes (or "tails" as usually they will be just the short connecting bits) need to be 15mm - so they will mate up to your radiator valves. The valves should be non thermostatic and they are cheap and easy to source. Use 22/15/22 tees from the spine to the tails.

If you go pressurised it's really very easy. Get a fill loop kit that has a gauge and pressure release valve (Webasto say the valve must be within 300mm of the hot pipe output I think, but you cannot achieve this with the fill loop kit so I used an extra valve nearer the output just to be safe). There are a couple of other inconsistencies in those detailed instructions - can't think what now - and you cannot contact Webasto via their website because it doesn't work.

Not sure what you mean by supply line - the diesel? Yes you can run a new bit of pipe but get the proper one - it has an unusual i/d. The supplier I got mine from cut my length into three and flared the ends for me, so with careful measuring you could go that way rather than trying to get them flared later. 

There are a number of tricky things such as odd hose sizes and unusual couplers - you'll have seen all that in my lengthy posts! 

You'll prolly end up completely redoing everything - make sure you have the inline fuel filter too. Good luck.

[starman]

1 hour ago, NMEA said:

Do you mean a Pro 50 vehicle unit or a pro 50 water station, the Water station is the only one approved for marine use and available in 24v only? Personally I would go pressurised, we fit almost exclusively these days, never fit thermostatic valves as the induce the boiler to cycle, not a good thing, the best thing you can do is have a good read of the Webasto marine install manual, it will answer all your questions and some you may not even have thought of yet. If you drop an email to ecmhe@talktalk.net I will ping you back a copy.

Sorry, I got a bit confused in my nomenclature.  The boiler is labelled Webasto Z/C - D while the installation instructions say 'Thermo 50 marine installation'

They do seem to suggest that the length of the fuel supply pipe is critical. Is that right? Also mine doesn't seem to have a filter - presumably a Bad Thing!

i want mine to be able to do

hw with rads off, ideally by lever valve. What would you class

as an adequate heat soak rad?

[nickfryer]

On 19/03/2018 at 08:14, NMEA said:

The TTC has only two heat levels so your pump speed reduction indicates a reduction to half heat. Good news is the new Thermo EVO is now available, it is fully modulated just like the air heaters so should go a long way to stop this happening, only in 24v at the moment though.

Thread Hijack 

 

Hi there NMEA. Can you tell me what the Thermo EVO is like in terms of reliability now it has been out a while?  

 

I have fitted two Webasto Thermotop C 5.2kw (the marine ones) in two boats over the last five years and have been highly delighted with the reliability and use.

 

I now have a small 2 bed holiday chalet, (no gas) and I am considering putting a Webasto in here. 6 Radiators and hotwater but do I go for the newer Thermo EVO or stick with the Thermotop C ?  I would appreciate your views on this.  Thanks.  Nick

[NMEA]

23 hours ago, nickfryer said:

Thread Hijack 

 

Hi there NMEA. Can you tell me what the Thermo EVO is like in terms of reliability now it has been out a while?  

 

I have fitted two Webasto Thermotop C 5.2kw (the marine ones) in two boats over the last five years and have been highly delighted with the reliability and use.

 

I now have a small 2 bed holiday chalet, (no gas) and I am considering putting a Webasto in here. 6 Radiators and hotwater but do I go for the newer Thermo EVO or stick with the Thermotop C ?  I would appreciate your views on this.  Thanks.  Nick

Bit early to make any informed comment yet Nick, However the Evo has been used in vehicles for a long time now without major issues, I am fitting one to my New Shogun and am not concerned. If you are putting six decent sized rads in a cabin and want hot water also I would be looking at a Kabola Compact 7 Combi to be honest.