Warwick XL - Whale heating system help needed

I’m a new year and need some help with why my heating system / pump seems to have air trapped in system that causes an issue when the water level drops. I can also see water coming out of the back of the van at this time that is from the heated tank, any advice welcome 

Also is there an internally accessible fresh water tank inspection chamber? A campsite neighbour was surprised I couldn’t find one?

Many thanks

Hi [You must be registered and logged in to see this link.]om,
My name is Hayley and I work in the marketing team at Whale.
Please feel free to contact our Customer Service Team who will do all they can to assist you with your query. You can call them on 0345 9090 911 or email [You must be registered and logged in to see this link.].
Alternatively, please privately send me the best number to get you on and I will get one of our team to give you a call.
Best wishes,
Hayley

Just to remove any doubt, are you sure your drain valve is closed?

Thanks for replying Don - yes I believe so as in the on/off lever accessible from within the campervan. I’ve learnt from a dealer there could be a switch to regulate the pump pressure, however not sure if the pump on mine is integral. I shall call Hayley tomorrow at Whale just missed her tonight. Thanks again TOM

Thanks Haley will call tomorrow morning on number you’ve passed to me. I tried but after 5pm and left a message

Hi Tom,

Did you get Whale problem solved?

I’m hoping so but working since returning from our break so not had chance to run water again yet, did you have some thoughts ? Be glad to hear another view thanks

TOM wrote:I’m hoping so but working since returning from our break so not had chance to run water again yet, did you have some thoughts ? Be glad to hear another view thanks

No, I don't have another view Tom just interested in the problem you're having, hope you get it sorted.