Spare Heating Coil in Cylinder?

mchammer

Hi All,

I have a 500 litre hot water tank and by the looks of it there is a spare coil that I am not using at the moment. There are 2 ports which are capped and labelled primary inlet and primary outlet. The model I have is a HT 500 ER from havel therm or Austria Email. Can anyone confirm for me that this is the case or is there a chance that they are just blank ports capped off? I am grateful for any pointers as I hope to install an additional heat source to heat the hot water as the current one is not heating as well as it should.
Thanks
MC

http://www.austria-email.com/fileadmin/content-en/Products/Freestanding_cylinder/HT_ER_ERR/HT_ER_ERR_115-500__237_744-2__engl.pdf

https://www.dropbox.com/s/5dhk63b0o6d8dzn/2015-02-04%2021.17.58.jpg

https://www.dropbox.com/s/32xmgq66xbqs38y/2015-02-04%2021.17.28.jpg?dl=0

Calahonda52

its tough to know, from pic 2, what is currently connected other than the very bottom cold water indeed.
Could you mark on the sketch in the brochure whats connected and maybe take a foto and post it?

Outkast_IRE

From a quick glance at the brochure and your pics i will hazard a guess that yes you do have a spare coil it is intended as a solar coil, you are saying that the current coil is not heating as it should .

Can i ask is the coil that is currently connected, the top coil on the cylinder ?

If you have two coils like this the usual reason is that the bottom coil is intended to be connected to solar, and the top coil to your boiler.

As the cylinder is designed to be used with solar the top coil only heats up the top half of the tank, this is why you think the current one is not heating as well as it should.

You could rectify this problem by either
1. getting a plumber to connect this bottom coil to the existing system, this is prob the cheapest option and should be effective, you may need to move the position of the zone thermostat to a lower sensor pocket, whoever is doing the job should be able to see quickly if this is necessary.
2. Using it for solar or another heat source.

mchammer

Thanks for the replies. Below is another image explaining what is connected at the moment. The reason I am looking at this is the geothermal heat pump struggles to get up to full temp during the cold spell when the mains water is coming in at only a few degrees I guess it has to work harder for longer. We never really run out of hot water (unless the mother in law is around) but I was thinking of installing some solar panels to take a bit of the pressure off the heatpump and so the ground gets a chance to recover during the summer when the solar can do most of the work. I should say the heatpump is connected at the bottom of the tank via the circular flange and it has a horizontal heat exchanger/element which was bolted on after the tank arrived

https://www.dropbox.com/s/kh5lhcltgkd48uv/hw.jpg?dl=0

I am thinking maybe of removing the cap at the primary inlet and seeing if the water comes gushing out?? not very scientific but if it is a coil the water should stop after a second or so??

Outkast_IRE wrote: »

From a quick glance at the brochure and your pics i will hazard a guess that yes you do have a spare coil it is intended as a solar coil, you are saying that the current coil is not heating as it should .

Can i ask is the coil that is currently connected, the top coil on the cylinder ?

If you have two coils like this the usual reason is that the bottom coil is intended to be connected to solar, and the top coil to your boiler.

As the cylinder is designed to be used with solar the top coil only heats up the top half of the tank, this is why you think the current one is not heating as well as it should.

You could rectify this problem by either
1. getting a plumber to connect this bottom coil to the existing system, this is prob the cheapest option and should be effective, you may need to move the position of the zone thermostat to a lower sensor pocket, whoever is doing the job should be able to see quickly if this is necessary.
2. Using it for solar or another heat source.

Calahonda52

thanks for this.

Anyway the ER tank is a single coil tank plus the flanged connection so the coil is available.
There should be no water in it.

P presume the SP should be sized based on the capacity of the heat coil as shown in the brochure, I don't know, its beyond my pay grade.
Thanks again for pics, great what you can learn from the desktop
In passing, how is the heat pump serviced

mchammer

Calahonda52 wrote: »

thanks for this.

Anyway the ER tank is a single coil tank plus the flanged connection so the coil is available.
There should be no water in it.

P presume the SP should be sized based on the capacity of the heat coil as shown in the brochure, I don't know, its beyond my pay grade.
Thanks again for pics, great what you can learn from the desktop
In passing, how is the heat pump serviced

sound - thanks for looking..
The heatpump doesn't need any servicing other than checking the gas levels of the refrigerant which you would do if you noticed a drop in performance. The compressor in them is 650watt which is pretty small and heats up the water at night time. I have a rural nightsaver so it is costing 8c kw/h which means for every hour the heatpump is running it is costing around 6 cent. It runs on average 5-6 hours a night around this time of year (dependent on usage) so that is roughly 30c a day - fairly happy with it but thinkk the solar would be a good addition to ensure the longevity of the heatpump