Truma Combi diesel / electric water / space heater. Vents some water at end of water heating cycle.

[ProDave]

I have the above Truma combi diesel heater. A few questions:

First and most urgent question, is when it is heating just hot water, at the end or close to the end of finishing heating, it vents a small amount of water. Google tells me this is normal but I am not sure.

I have looked at the install and user manuals and not found any mention of this.

Now in a domestic setting, if your hot water heater vents water, then it is usually a fault with the expansion vessel. Some domestic tanks have a separate expansion vessel, others like Megaflow just maintain an air bubble at the top of the cylinder and there is a procedure to regenerate that air bubble.

So returning to my Truma, is this really considered "normal" or do I have a fault?

As a sanity check here is one random supplier selling the kit https://www.grasshopperleisure.co.u...-heater-with-inet-x-control-panel-44076-p.asp

There is no sign of an expansion vessel included with that kit so it must be built in.

Second question, why does it take a full half hour to heat 10 litres if water hot enough for washing up? I have had 2 previous trailer caravans with Truma gas water heaters and they have always heated it in less than half that time,

 

[colinm]

I'll pose a third question.
Do people fire up the Truma to do the washing up, or boil a kettle for washing up, and only fire up the Truma if wanting a shower?

 

[ProDave]

I fire it up for washing up, because 1 kettle full is not enough.

 

[Fisherman]

I have the above Truma combi diesel heater. A few questions:

First and most urgent question, is when it is heating just hot water, at the end or close to the end of finishing heating, it vents a small amount of water. Google tells me this is normal but I am not sure.

I have looked at the install and user manuals and not found any mention of this.

Now in a domestic setting, if your hot water heater vents water, then it is usually a fault with the expansion vessel. Some domestic tanks have a separate expansion vessel, others like Megaflow just maintain an air bubble at the top of the cylinder and there is a procedure to regenerate that air bubble.

So returning to my Truma, is this really considered "normal" or do I have a fault?

As a sanity check here is one random supplier selling the kit https://www.grasshopperleisure.co.u...-heater-with-inet-x-control-panel-44076-p.asp

There is no sign of an expansion vessel included with that kit so it must be built in.

Second question, why does it take a full half hour to heat 10 litres if water hot enough for washing up? I have had 2 previous trailer caravans with Truma gas water heaters and they have always heated it in less than half that time,

I have the 4kw diesel only Truma combi and it does take a fair bit of time to heat the water, but if you have the 6kw diesel electric I would have thought it would heat the water faster. I have noticed that I get a small amount of water maybe around 25ml when heating water, I don’t know if I get this when heating the van. But as you will know when heating the van you also heat the water to the eco temp of 40c.
Word of warning try to avoid simply turning it of during the heating process.
This seems to create a fault, and you have to do a reset by holding the switch until you get a yellow light, this can be a pain if getting to the boiler is difficult.

 

[Boris7]

When stationary I just leave the hot water on all the time wether I’m on EHU or not.

 

[TJBi]

I'll pose a third question.
Do people fire up the Truma to do the washing up, or boil a kettle for washing up, and only fire up the Truma if wanting a shower?

Boil a kettle for washing-up; it's normally been put on for hot drinks anyway. You can run off a lot of cold water to get hot through the pipes.

 

[horace]

Hi Dave the boiler unit does let a little water out on expansion , you can open the hot tap for a second or as you said fit a 2 litre expansion vessel in the hot pipe so its the same as your home megaflow

I have the above Truma combi diesel heater. A few questions:

First and most urgent question, is when it is heating just hot water, at the end or close to the end of finishing heating, it vents a small amount of water. Google tells me this is normal but I am not sure.

I have looked at the install and user manuals and not found any mention of this.

Now in a domestic setting, if your hot water heater vents water, then it is usually a fault with the expansion vessel. Some domestic tanks have a separate expansion vessel, others like Megaflow just maintain an air bubble at the top of the cylinder and there is a procedure to regenerate that air bubble.

So returning to my Truma, is this really considered "normal" or do I have a fault?

As a sanity check here is one random supplier selling the kit https://www.grasshopperleisure.co.u...-heater-with-inet-x-control-panel-44076-p.asp

There is no sign of an expansion vessel included with that kit so it must be built in.

Second question, why does it take a full half hour to heat 10 litres if water hot enough for washing up? I have had 2 previous trailer caravans with Truma gas water heaters and they have always heated it in less than half that time,

at home .

 

[horace]

We have been to truma with this fault and they changed the 4 bar safety valve to 4.5 safety valve that slowed it down only.

 

[guerdeval]

Mine heats much faster on gas than electric