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Truma Ultra Store - 12v Amp Usage on Water Heating

6.3K views 5 replies 3 participants last post by  Ian_n_Suzy  
#1 ·
Truma Ultra Store - 12v Amp Usage on Water Heating

Hi,

Do any of you know what (if any) the amps drawn from the 12v Battery are if a Truma Ultrastore is left on the Water Heat setting? I can't say I've ever noticed if the fan kicks in at all when only on the water heater.

(I'm thinking of leaving it on over night as much as possible whilst away from EHU).

Any help / info would be greatly appreciated - THANKS IN ADVANCE
 
#2 ·
The operating and installation book doesn't give a figure for 12V, and that is presumably for the control side, but if you add in a gas valve, water valve and a bit of control stuff, you'd be getting on towards 10Amps if it was all on, and the wiring instructions do suggest a 10A fused supply.

Peter
 
#3 ·
I don't think the Ultrastore takes much from the 12v supply - just whatever the thermostat/control system needs which I suspect is minimal. When we're away and not on EHU we leave the hot water on gas all the time with no issues (we have a solar panel for trickle charging whenever the sun comes out!).
Bill
 
#4 ·
Thanks for the replies, I am hoping that as Bill says it uses very little (I was thinking less than 1ah).

Peter, won't the 10ah figure be for when the fan and water heating are both on? (I'm sure I have previously measured the draw on the blown heating fan as circa 4ah, though this was some time ago so I may well have this figure wrong).
 
#5 ·
The fan is the heaviest consumer, but I have no figures for what is on during water heat only, but there must be a gas valve and I assumed a water valve as well, otherwise you couldn't split the water and air heating.

Peter
 
#6 ·
I've managed to find an online .PDF file with the info in.

For future reference of others who may search the forum, this is the info from the manual.

Current input at 12 V

Heater + water heater
C 4002: 0.2 – 5.6 A
(average power
consumption 1.3 A)

C 6002: 0.2 – 5.6 A
(average power
consumption 1.4 A)

Heating up of water heater:
0.4 A

Stand-by:
0.001 A