Hi all, I have a 2008 Lunar caravan with external submersible water pump.
I fitted a new pump and pressure switch recently.
My problem is all cold water is working fine, but. I don't think the hot water tank is filling up. When I open both hot water and cold water they both work.
When I. Switched the water heater on it tripped the breaker I assume because there is no water in the tank.
I am on site at present with very poor Internet supply.
Any advice would be appreciated
If water is coming from the hot tap the tank must be filling. I suspect the breaker tripping is a different issue. Maybe the heating element has failed and gone short circuit? It can happen anytime.
Quite often the hot supply is limited by an air lock in the hot water pipework, and therefore the hot tap needs to be opened and shut a few times to allow the air to be purged out of the system. Sometimes the submersible pump floats on the top instead of dropping so check that out too. Never switch the water heater on until it flows smoothly in the hot side, but I suppose you found that out the hard way I'm afraid.
Dave.
------------- Never argue with an idiot, they will drag you down to their level and beat you on experience.
Mark Twain.
If the mains breaker is tripping, that's more an indicator of an electrical fault, like a heating element fault, but whatever, it's an electrical overload, not overheating due to lack of water in the tank. The fact that the breaker trips instantly the heater is switched on is another clue, it would take a little time for an overheat due to lack of water to trip it, there is no water level sensing device fitted that will trip anything. There is often a thermostatic trip on the tank itself that deals with overheating - automatic trip, manual reset.
It usually takes a little longer on first fill to purge all the air from the hot water system, than it does from the cold system, as the hot water tank needs filling (usually circa 10L), there's often a bit of spitting and spluttering before water runs smoothly. Unless you have replumbed the system different to standard, once the hot water taps run smoothly, the tank is full, as it fills from the bottom and draws from the top.
As you've been working in the vicinity of the water tank (pressure switches are normally located nearby), I'd have a careful look for any damaged mains cabling, and the power connections to the water heater itself. All too easy to inadvertently catch cables in the confines of a typical locker!
As you are dealing with mains electricity, ensure EHU is disconnected when investigating, just in case you do discover damage/exposed cabling/connectors!
Thanks. For your replies guys. I drained the water down again but this time a lot of air was coming out of the hot tap, I can only think like you said an air lock in the hot tank.
Many thanks GCB
It sounds like the hot water is syphoning back into the aquaroll, try putting the pump into a small jug to check, if it is it may need a new non return valve, or you could try cleaning it.
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Topic: Hot water Tank
via mobile 22/4/2025 at 8:27pm
