Geekzone: technology news, blogs, forums
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.

1 post

Wannabe Geek

Topic # 191422 3-Feb-2016 18:54
Send private message





My first post, hello everybody. Have just purchased a doer upper in the BOP and first up is the heating - need to get something set up for winter.




Currently has a woodburner with wetback, directly heating the HWC. Low pressure, open vented, no pump, works perfect.




It is my wish to add 2 or 3 radiators to this system, but as it is direct (no heat exchanger in the HWC) i am faced with the challenge of keeping the two mediums separate, as i do not wish to drink radiator water!


current ideas are:


an extra wetback coil in the wood burner and independent radiator circuit




heating either the radiator circuit or the HWC indirectly, with a heat exchanger. The easiest solution for me would be to send the water from the wetaback to a heat exchanger and one heat sink rad, and pipe the domestic hot water around the heat exchanger to heat it up. Would this work? i could then possibly add another 2 radiators on a pumped circuit etc etc.


My main question is, would the heat exchanger and heatsink rad from the wetback be enough to heat the hot water, and what type of heat exchanger should i aim for?




I am aware of having to open vent the new circuit and include a header tank etc etc





Create new topic
2129 posts

Uber Geek
+1 received by user: 704


  Reply # 1484729 3-Feb-2016 19:30
Send private message

How many kW output is your wetback? No point bothering if it is only a 1kW output one.




Best system would be a combined water circuit for the wetback and radiators. With the cylinder water separate. Would be expensive as you will need a custom heat exchanger, 2 pumps, suitable controls. But will give you best flexibility, allow cylinder temp to be regulated, and you will be able to convert to a mains pressure wetback system if you replace the hot water cylinder. (using an off the shelf cylinder instead of a wetback one as well).




Cheaper systems will have controllability issues. and no upgrade path to mains pressure hot water.




Also have you considered a heat transfer system? (ducting from lounge to bedrooms, with a thermostat to switch fan on when lounge is warm).




And the biggest question - does the system need to fully comply with council rules?

Create new topic

Twitter »

Follow us to receive Twitter updates when new discussions are posted in our forums:

Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:

Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:

News »

New Zealand hits peak broadband data
Posted 18-Jan-2018 12:21

Amazon Echo devices coming to New Zealand early February 2018
Posted 18-Jan-2018 10:53

$3.74 million for new electric vehicles in New Zealand
Posted 17-Jan-2018 11:27

Nova 2i: Value, not excitement from Huawei
Posted 17-Jan-2018 09:02

Less news in Facebook News Feed revamp
Posted 15-Jan-2018 13:15

Australian Government contract awarded to Datacom Connect
Posted 11-Jan-2018 08:37

Why New Zealand needs a chief technology officer
Posted 6-Jan-2018 13:59

Amazon release Silk Browser and Firefox for Fire TV
Posted 21-Dec-2017 13:42

New Chief Technology Officer role created
Posted 19-Dec-2017 22:18

All I want for Christmas is a new EV
Posted 19-Dec-2017 19:54

How clever is this: AI will create 2.3 million jobs by 2020
Posted 19-Dec-2017 19:52

NOW to deploy SD-WAN to regional councils
Posted 19-Dec-2017 19:46

Mobile market competition issues ComCom should watch
Posted 18-Dec-2017 10:52

New Zealand government to create digital advisory group
Posted 16-Dec-2017 08:47

Australia datum changes means whole country moving 1.8 metres north-east
Posted 16-Dec-2017 08:39

Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.

Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.