Hello everyone
As a temporary living space (during the house renovation), I am currently building a caravan that stylistically resembles a circus wagon. It includes a small shower and a compact kitchen. (Plans are attached as a PDF)
My original idea to heat the water with an instant water heater turned out to be unfeasible (too high power consumption). So, the only option left is a boiler. It should not be larger than necessary, as space is limited. I am even considering purchasing a horizontal model and installing it below the floor, essentially in the chassis, and surrounding it with an insulated wall.
The question is: How big does it need to be? It must be sufficient for 2 people to shower within one hour (assuming the showering time is kept as short as necessary). Various figures regarding water consumption for showers and the minimum size of a boiler for a small two-person household circulate online. I think it should be at least 100 liters (26 gallons).
Does anyone have experience with this? Any recommendations?
Thanks and best regards
Michael
As a temporary living space (during the house renovation), I am currently building a caravan that stylistically resembles a circus wagon. It includes a small shower and a compact kitchen. (Plans are attached as a PDF)
My original idea to heat the water with an instant water heater turned out to be unfeasible (too high power consumption). So, the only option left is a boiler. It should not be larger than necessary, as space is limited. I am even considering purchasing a horizontal model and installing it below the floor, essentially in the chassis, and surrounding it with an insulated wall.
The question is: How big does it need to be? It must be sufficient for 2 people to shower within one hour (assuming the showering time is kept as short as necessary). Various figures regarding water consumption for showers and the minimum size of a boiler for a small two-person household circulate online. I think it should be at least 100 liters (26 gallons).
Does anyone have experience with this? Any recommendations?
Thanks and best regards
Michael
M
Michael CH7 Jan 2016 22:06EveundGerd schrieb:
The water heater also works with vehicle power, so at 12 V. In the technical specifications, it is listed as 230 V / 1.3 A. An instantaneous water heater that serves a shower must heat at least 6-8 liters of water per minute, which in winter might be around 5°C (41°F), up to 42°C (108°F). 6-8 liters per minute! That obviously requires a lot of energy. Take a look at the technical data of such devices.
EveundGerd schrieb:
An electrician does not necessarily have expertise in electrical components installed in campervans or motorhomes. Truma also offers boilers. These require far less than your 24 A. Yes, that’s exactly why I don’t want an instantaneous water heater, because a boiler obviously doesn’t require such high power. I just never really know how large the boiler should be. And that’s what this thread is about.
EveundGerd schrieb:
Have you even studied this topic thoroughly? My question as to why you don’t simply invest in a caravan instead of spending a lot of money and time on a conversion hasn’t been answered yet. I have. Very thoroughly! You can be sure I have good reasons.
M
Michael CH7 Jan 2016 22:11T21150 schrieb:
You don’t necessarily have to power such a device with electricity... and since it used to be a circus trailer, there should be a gas bottle container plus gas line.It is not a "former" circus trailer. It is a new build (see first post).
And the question is not WHETHER the device can be powered by electricity. I could easily operate a 2000-liter (530-gallon) boiler. Unfortunately, there is not enough space for that. I can fit a maximum of 200 liters (53 gallons) inside. I would actually prefer it to be less... I’m just not sure what the minimum capacity should be.
M
Michael CH7 Jan 2016 22:42T21150 schrieb:
Estimated requirement = 120 liters (31.7 gallons).Hello Michael,
The Swedish water utility formula calculates a shower time of 5 minutes per person with 8 liters per minute. This is generally accepted and also forms the basis of our standards.
That means 2 persons x 5 minutes x 8 liters = 80 liters. A horizontal storage tank has a draw-off factor of 0.8 due to temperature stratification, while a vertical one has 0.9.
The desired shower temperature should be 38°C (100°F) (assumption). This results in a storage temperature of 100 liters.
Since the water should be about 60°C (140°F) for grease removal during dishwashing and to reduce Legionella, a storage tank of 56 liters with a horizontal arrangement is required.
The selected storage tank is 50 liters at a storage temperature of 66°C (151°F).
For very hard water, the temperature should not exceed 60°C (140°F) to avoid heavy scaling of the heating elements. When choosing the storage tank, you need to check what the manufacturer offers. The electric connection power can usually be adjusted between 2, 4, or 6 kW, where I recommend 2 kW. The heating time from 10 to 60°C (50 to 140°F) is then about 1.5 hours.
This allows 2 people to shower one after the other with good comfort—I wish you much fun and enjoyment.
Best regards, sonniba
The Swedish water utility formula calculates a shower time of 5 minutes per person with 8 liters per minute. This is generally accepted and also forms the basis of our standards.
That means 2 persons x 5 minutes x 8 liters = 80 liters. A horizontal storage tank has a draw-off factor of 0.8 due to temperature stratification, while a vertical one has 0.9.
The desired shower temperature should be 38°C (100°F) (assumption). This results in a storage temperature of 100 liters.
Since the water should be about 60°C (140°F) for grease removal during dishwashing and to reduce Legionella, a storage tank of 56 liters with a horizontal arrangement is required.
The selected storage tank is 50 liters at a storage temperature of 66°C (151°F).
For very hard water, the temperature should not exceed 60°C (140°F) to avoid heavy scaling of the heating elements. When choosing the storage tank, you need to check what the manufacturer offers. The electric connection power can usually be adjusted between 2, 4, or 6 kW, where I recommend 2 kW. The heating time from 10 to 60°C (50 to 140°F) is then about 1.5 hours.
This allows 2 people to shower one after the other with good comfort—I wish you much fun and enjoyment.
Best regards, sonniba
Similar topics