HRM Wallstar air problem

well well well....I contacted my highly recommended heating engineer (not going to say who he works for but they happen to make said boiler! ) who confirmed that a tiger loop was indeed not recommended for HRM wallstar but I managed to convince him to install one.....and, at a stroke ALL the air bubble problems have gone !!!
There are still micro bubbles coming in from the supply pipe (I specifically requested he use clear oil lines) probably due to the vacuum caused by lifting the oil and if you tap the fire valve it also produces a stream of bubbles (yes, I have replaced it with a quality Valspar one and every connection throughout is sealed with Heldite) but after a second or so they arrive at the tiger loop and are quickly separated from the oil

The boiler also shuts down pretty much instantly and certainly more quietly which confirms that no air is getting to the injector

thanks to all who persevered in recommending its' fitment :)
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I don't know why your engineer and others say that a Tiger Loop is not recommended, the MIs I looked at just said it's not required?, because it's a deaerator I can't see why it isn't highly desirable to install one where the tank is below the burner, anyway, all's well that ends well.
the manufacturer instruction specifically states that tiger loopMUST NOT be fitted and doing so will invalidate warranty!
I am wondering if they are referring to a two pipe system ?

When the boiler is doing its 10 or 12 sec purge and the oil is just circulating around the T.loop, do you still see bubbles in the T.loop pipes, or is it just for the few seconds that you mention above?
When the burner is firing it will still be circulating oil around the loop, what do you observe then?
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yes, when it does the initial purge I see a few small bubbles entering the TL, when it is firing there are only the tiny micro bubbles
We have converted a number of these boilers to tiger loop work well.
If they are out of warranty where's the problem?
The air bubble problem seems worse when the the pump is doing near maximum lift.
One site where we look after several wallstar boilers had underground oil tanks. Dreadful mix some properties resorted to above ground tanks others we converted to tigerloop when out of warranty.
My oil service engineer had a 'of the record ' conversation with HRM technical who admitted the small champagne type bubbles were caused by the oil pump.
Wonder why installing a T.loop during warranty invalidates it.
I would have a concern re using flexible hoses (especially clear plastic) on the T.loop as its possible that substantial pressures could build up if it malfunctioned?
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Wonder why installing a T.loop during warranty invalidates it.
I would have a concern re using flexible hoses (especially clear plastic) on the T.loop as its possible that substantial pressures could build up if it malfunctioned?
I half suspect the no tigerloop thing is as much to do with sales as anything (we don't need it sort of thing)
Its rare we use a wall mounted oil boiler but certainly won't use wallstar's having seen possible issues.
I think that's unfair
After some 26 years in use, apart from the air bubbles issue causing repeated lock-outs ....which is now sorted, I can honestly say we are totally 100% satisfied with burns cleanly with no soot and no smell, it is very economical, very neat and compact, the engineer reports it is amongst the lowest CO and CO2 levels he has ever seen (so therefore very efficient) it is virtually silent in operation and, in 26 years it has been the pinnacle of reliability and has never broken down or let us down.
In all that time it has only needed a replacement pump, new bearings in the fan motor and the occasional nozzle, it has always been serviced by HRM (I take the burner out and take it to them) every 3 years or so and thats it....very cheap indeed :)
Dont discount their use and dont knock the company.........and no, I have no affiliation or interest with them, just a very happy customer
So it's a great boiler apart from when there's a air bubble pulled through oil pump?
A problem HRM are aware of and just refuse to address?
As a business we install better than 2 oil boilers a week and maintain/service oil boilers and cookers well into 4 figures.
Do you really think I would recommend/install a boiler with a known long term issue?
Our reputation financial well being and peace of mind is worth more than that.
You have experience of one wallstar boiler we have the experience of many.

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