Domestic heating with additional Webasto and Summer/Winter mode

[RoyLittle0]

Hi All,

 

We are in the middle of a fit out of a 50ft narrowboat and are looking to improve the heating and domestic hot water system, the current system works well but the heating is a little slow to heat up the radiators, which we know is due to the Refleks output, this is a system we have chosen for cleanliness and medical reasons.

 

What we want to do is give the Refleks a boost and add some Summer, Winter functionality to it, so we are proposing to fit a Webasto type of unit in to allow us to heat the radiators more quickly and also heat the hot water calorifier without running the engine.

My idea is shown in GREEN and I have added a 2 position valve to add the Summer/Winter functionality and also keep the existing expansion tank in the system

 

edit: Looking at the position of the 2 way valve it won't work, time for a rethink and redraw

Any thoughts or improvement ideas, all ideas welcome but please keep your rants or personal bickering to yourselves

 

 

Edited September 1 by RoyLittle0

[GUMPY]

When we had our Old Dutch (similar to the Refleks) we ran the rads from the Eberspacher and removed the coil from the Old Dutch so we were running two separate systems.

You will have to be careful with running two systems combined as a diesel heater needs to run hard and will short cycle if there is a secondary source of heat in the system.

 

 

 

 

I did look at adding a heat exchanger between the systems but decided it wasn't worth it.

[RoyLittle0]

24 minutes ago, GUMPY said:

You will have to be careful with running two systems combined as a diesel heater needs to run hard and will short cycle if there is a secondary source of heat in the system.

The plan would be to use the Webasto type of heating to give the initial boost to the system, so I envisaged running it for maybe 30 to 40 minutes, which would give the Refleks time to heat up and be able to maintain the heat, I personally don’t think its man enough to do it on its own, so it needs a boost, but the main reason for the change is for the Summer use, to heat the water without running the engine.
 

But looking at the drawing again, it wouldnt work the way its drawn, the 2 way valve needs to break the existing system somehow, Hmmm, time for a rethink

Edited September 1 by RoyLittle0

[GUMPY]

When we lived on board we never let our stove go out between November and March so no need for a boost. When we moved off and were coming up to the boat I just turned on the Eberspacher as I left home, 4hrs later when we arrived the boat was warm. That is simply done using a Remote switch SMS controlled so no WiFi/internet needed.

There is really no reason to combine the systems if you do there is no redundancy in the event of a fault. 

[RoyLittle0]

I already have a similar setup using a cheap Chinese diesel hot air blower system, which was initially a temporary setup whilst I was stripping the boat during the winter, I can turn it on from home remotely and it heats a good % of the boat, but obviously that heats the boat and not the domestic hot water, hence why I am trying to find a way to incorporate a way to heat calorifier which is already part of the radiator system

30 minutes ago, GUMPY said:

That is simply done using a Remote switch SMS controlled so no WiFi/internet needed.

Thankfully I have Wi-Fi on 24/7

 

But just an FYI for anyone else reading this, the sms Remote switch linked uses the 2G network and has been phased out and will be permanantly shut down in a few years, so not a long term solution, look for a 3G 4G unit

[colin stone]

As a slight aside, rather than the engine just heating one calorifier, I put a Bowman tube heat exchanger directly into the boiler hot out pipe to the radiators and calorifiers and connected it to engine calorifier connections. Once the engine has warmed up, a delay on relay switches on CH pump and hot water circulates the whole system. Radiators have TRVs, so in summer only the pipes to/from calorifiers get any water flow. 

The twin coil calorifier now has generator coolant through one coil and CH through the other. 

[GUMPY]

41 minutes ago, RoyLittle0 said:

look for a 3G 4G unit

3g has already been turned off in the UK

2g it will be 2030 at the earliest before it goes, there is far too much infrastructure stuff running on 2g that has to be moved. 

2033 is the final cut off date for 2g

50 minutes ago, RoyLittle0 said:

Thankfully I have Wi-Fi on 24/7

As do I but many don't 

I use Sonoff  SV switches and eWeLink to control stuff in the caravan and at home. 

Works very well.

[cuthound]

20 hours ago, GUMPY said:

When we had our Old Dutch (similar to the Refleks) we ran the rads from the Eberspacher and removed the coil from the Old Dutch so we were running two separate systems.

You will have to be careful with running two systems combined as a diesel heater needs to run hard and will short cycle if there is a secondary source of heat in the system.

 

 

 

 

I did look at adding a heat exchanger between the systems but decided it wasn't worth it.

 

 

I agree, best to supply the radiators just from the Webasto and use it for those chilly spring and autumn mornings and evenings. Reserve the Refleks to winter heating when you can run it 24/7, with a break to clean it every 500 hours.