Just replaced electric heating element in my 2012 year model Truma b14 hot water unit with an 850watt element and after 1hour 15minutes the water is barely warm. I would expect that it should be quite a bit hotter than that as the old element would heat it up in about 45 minutes. Is there anything that I may be overlooking as I'm new to a van with a hot water unit in it.
The old element would trip the circuit breaker as soon as I turned it on using 240 mains power but would not trip the generator circuit breaker if I plugged it directly into the generator bypassing the van circuit breaker. Even with the old heating element I felt that it should have provided a little more water before it went cold although I realize 14 ltrs of hot water isn't much.
Pete
Ineedabiggerboat said
06:10 PM Oct 9, 2025
Ive got a rule with small tank showers.
Wash and rinse your hair first.
Nothing worse than a head full of bubbles and no hot water
Peter_n_Margaret said
06:52 PM Oct 9, 2025
Measure the current drawn.
Cheers,
Peter
Black-Pete said
08:11 PM Oct 9, 2025
I measured the ohms resistance on the old and the new elements when I had the old element out before I put the new one in. Old one was 64 ohms new one was 61 ohms.
The current draw on the new element should be, if my maths is correct, about 3.55 amps. I will measure it early next week when I have more time.
Pete
Mein said
11:23 PM Oct 9, 2025
1. My van had a single 10 litre hot water storage unit, which I found didn't provide enough hot water on chilly mornings. I added a second 10 litre unit, inline. I haven't yet run out of water with 20 litres. I can isolate either unit so that, in the summer, I can revert to 10 litres.
2. A circuit breaker in the van, one of 3 (but 1 is exclusively for the air con) would randomly trip. No pattern to its tripping. Over time, I isolated each connected power outlet but couldn't determine why the circuit break was tripping. I replaced the circuit breaker itself and it has never again tripped.
67HR said
10:26 AM Oct 13, 2025
Could it be the circuit board.
DMaxer said
01:37 PM Oct 13, 2025
Before you do anything else, turn off at wall power point, pull out electrical plug from wall, wait about ten minutes and then plug electrical cord back into power point and switch back on.
Worked for mine.
Black-Pete said
08:33 PM Oct 14, 2025
DMaxer, Did you leave the 12v connected or did you disconnect the 240v as well as the 12v system.
Pete
DMaxer said
08:57 PM Oct 14, 2025
Hi Pete. My model Truma is the same as yours. Some time back it ceased and I thought it had died. A fellow camped nearby told me to try doing that. I left the battery connected and just turned the hws off at the power point and pulled out the electric cord from the power point. After ten minutes plugged the cord back in and turned it back on and voila. It just reset and no more probs.
I have done the same with phones and laptops.
A few encouraging words and questioning its heritage doesnt go astray either. Hope that helps.
Black-Pete said
06:47 PM Oct 22, 2025
I had another look at the hot water unit today and after one and a half hours of heating I drained the shower water into a bucket and as soon as it went col I turned it off. I got 3 ltrs of water at 22degs.
I was about to drain the unit when I touched the water unit and it was quite warm, then I felt the outlet pipe and it was very warm and I could only just hang onto it. Long story short it appears the temperance valve is blocked. Will play with it tomorrow and see if it's blocked and will report back with what I find.
Pete
67HR said
11:13 AM Oct 23, 2025
Black-Pete wrote:
I had another look at the hot water unit today and after one and a half hours of heating I drained the shower water into a bucket and as soon as it went col I turned it off. I got 3 ltrs of water at 22degs. I was about to drain the unit when I touched the water unit and it was quite warm, then I felt the outlet pipe and it was very warm and I could only just hang onto it. Long story short it appears the temperance valve is blocked. Will play with it tomorrow and see if it's blocked and will report back with what I find. Pete
Pete, you can usually adjust the tempering valve to by pass its operation. I had a similar situation and after removing it found I could do little unless it was replaced. However I was able to adjust it so I was able to get very hot water, you just have to take care using the taps. You can adjust the mixer to do this.
Black-Pete said
10:23 PM Oct 23, 2025
I pulled the tempering valve out today and dismantled the valve and found very little crud in it. put back together and wound the adjustment right up and now I still get only 3 ltrs of warm water but now its 34 degrees. I think I will need to replace the valve. Bypassing it is an option but the nearest place that MAY have the fittings needed is 90km away. While I was checking if there was a secondary valve anywhere in the system I found water was dripping from the connections under the sink which was just a mater of removing all the thread tape and just tightening up the connection so it seated on the rubber seal in it. I don't really understand why I'm only getting 3 ltrs before it goes cold as I would have thought it would run cooler water until the 14ltrs in the water unit was exhausted.
Pete
Black-Pete said
03:14 PM Oct 28, 2025
Fitted new tempering valve today and I now have hot water and I filled a 20litre bucket with it and it was still hot at 50degrees so I'm a happy chappy.
Pete
Ineedabiggerboat said
05:05 PM Oct 28, 2025
Nice to see a good outcome
As a side note, years ago I had a Rheem off peak hot water system. It started to output water with a browny tinge on it. Water from cold tap was fine.
It was exactly 9 years and 9 months old.
Called Rheem. Ten year warranty. They organised Parramatta Hot Water to come out and replace it. All I paid was a small labour charge.
Its nice to have the occasional win. And deal with an honest supplier.
Just replaced electric heating element in my 2012 year model Truma b14 hot water unit with an 850watt element and after 1hour 15minutes the water is barely warm. I would expect that it should be quite a bit hotter than that as the old element would heat it up in about 45 minutes. Is there anything that I may be overlooking as I'm new to a van with a hot water unit in it.
The old element would trip the circuit breaker as soon as I turned it on using 240 mains power but would not trip the generator circuit breaker if I plugged it directly into the generator bypassing the van circuit breaker. Even with the old heating element I felt that it should have provided a little more water before it went cold although I realize 14 ltrs of hot water isn't much.
Pete
Cheers,
Peter
The current draw on the new element should be, if my maths is correct, about 3.55 amps. I will measure it early next week when I have more time.
Pete
1. My van had a single 10 litre hot water storage unit, which I found didn't provide enough hot water on chilly mornings. I added a second 10 litre unit, inline. I haven't yet run out of water with 20 litres. I can isolate either unit so that, in the summer, I can revert to 10 litres.
2. A circuit breaker in the van, one of 3 (but 1 is exclusively for the air con) would randomly trip. No pattern to its tripping. Over time, I isolated each connected power outlet but couldn't determine why the circuit break was tripping. I replaced the circuit breaker itself and it has never again tripped.
Could it be the circuit board.
DMaxer, Did you leave the 12v connected or did you disconnect the 240v as well as the 12v system.
Pete
I was about to drain the unit when I touched the water unit and it was quite warm, then I felt the outlet pipe and it was very warm and I could only just hang onto it. Long story short it appears the temperance valve is blocked. Will play with it tomorrow and see if it's blocked and will report back with what I find.
Pete
Pete, you can usually adjust the tempering valve to by pass its operation. I had a similar situation and after removing it found I could do little unless it was replaced. However I was able to adjust it so I was able to get very hot water, you just have to take care using the taps. You can adjust the mixer to do this.
Pete
Pete