Hydronic Heating - Which Brand to Choose?

Mook I spoke to my installer last week and he said that, I'm sure it was, Uponor are bringing out a push fit connections and they are really good.

the baxi duo-tec ga boilers are now available in australia. 80 deg water and they are 96.7% efficient. Also the only boilers that are gas adaptive - senses the flame burn off and keeps the flames running at the hottest they can be. far superior technology than bosch or immergas imho

Hi there. We are in the market researching and obtaining quotes for a Hydronic Heating System for two Townhouses in Preston. So far the first quote we received was about 30K for two systems from Hydrotherm in Thomastown. They use the Bosch Boiler and Radiater Panels. The Townhouses are 220 meters squared each. Any suggestions to get some more quotes from reputable suppliers.

Hi - just found this thread as I look at hydronic heating in a new house my son is building in the Blue Mountains. I'm looking for advice on boilers. He is building the house in 3 stages over 3-4 years. The initial stage is 6.7kw, the next stage is an additional 2.5kW and the final stage adds 3.7kW. Have enjoyed learning about doing heat load calculations again (engineer I is!) and have created a spreadsheet to map out all the variables.
Looking at Baxi and Bosch heaters, but not sure if the size to the final house (total 12.9kW) will modulate down to the 6.7kW of the initial stage. Getting confusing responses from companies.
Does anyone have knowledge that can help?
By the way - apart from installing the boiler, we will probably be DIY for the piping and radiators - any experience people can add?

Russ

I'm pretty sure the Baxi dua-tec ga will be able to modulate right down to 5kw or so. I'll need to check to confirm as I'm considering that boiler as one I might go with for my hydronic install.

My advice to you would be work out what panels you intend to put where and add additional noggins for something solid to mount to.

Use good quality pex pipe and lag the pipes under the house, in walls or in ceilings.

Be sure to clip the pipes down securely with an adequate number of clips.

Use a decent thermostat to control the boiler as opposed to using either a no name one or the one that came with the boiler.

hth

got quoted for a hydronic system with copper pipes instead of plastic ones.

Is this a good thing or not? does it make the job more expensive?

mixo

I would of thought it would be more expensive.

I would have thought that too, but does copper make the system last longer, has less issues than plastic pipes?

mixo

I'm not qualified to answer that but plastic has better insulative properties than copper so I would assume less heat loss.

The issue of copper vs pex pipe is:

Cost - copper is dearer

Heat loss factor - the copper will loss more heat through the walls of the pipe due to having more (less?) heat loss factor. The pex pipe will also lose heat through the wall of the pipe but as it's generally layers of plastic and metal, it's not as much as copper. Both will benefit from pipe insulation.

Erosion - water flowing through the copper pipe will over time wear away the inside of the pipe wall with a sandpaper like effect.

Workability - the copper is generally easier to work with and form into place.


If you don't mind me asking mixo, roughly how much was the quote with copper pipe?

I thought the pex would be easier to work with as it can be bent without tooling

Maybe I should have said copper is more malleable. Copper can also be bent without tools, just depends on how you do it but once bent will tend to hold a shape much easier whereas the pex pipe needs to be secured in place to hold it in a certain shape.

My opinions are my own though formed after speaking to some plumbers I work fairly closely within my line of work who have used copper pipe, steel pipe, pex pipe and abs plastic pipe.

For a 32 sq home with 11 panels and a 35kw boiler which the name escapes me at the moment around the 15.5K mark...

Now that a big difference from a central heating gas system quoted by the builder at around 6.5K

Getting more quotes..

mixo

I've got a similar size install of 9 panels and 2 towel rails with a 35kW boiler for $14.5k. This price is for installation with pex pipe.

didnt get the towel rails, not sure they are worth the cost in what they do.I have tastic lights instead in the bathrooms.

Might change my mind, but i haven't got anyone I know who has hydronic hand rails to check out how they work and if they work properly.

mixo

I personally hate the tastic lights. Their heat is too concentrated to underneath them.
Besides the cost to run them I believe is far more.
The towel rail would only be a hundred dollars or so more.

The whole idea of hydronic is to have a relatively even temperature throughout the house. If you don't want that then don't waste your money on hydronic because the cooler rooms will make the system less effective.

hmmm, you might be correct, but in reality how long are you going to be in the bathroom??

Couple of minutes to do your business or 5 to 10 minutes for a shower?

Not sure its worth heating up a room your going to be for a few minutes.

Not convinced yet!

mixo

As well as heating the room, the towel rails double as a towel warmer/dryer so that you don't end up with damp towels hanging for extended times in the bathroom. I've also got heat/fan/light assemblies going into both bathrooms so the option of the heat lamps is there but I'd rather the even heat from the hydronic.

+1

I forgot about the other great reason of not having wet towels in winter.
Shower twice a day and you're changing towels every 3-4 days

How fast do the towel rails dry a wet towel.
I live in Melbourne, house empty during the day, heating will be on usually between 5 to 10 in the morning and 3 to 1am at night.Will that be enough time to dry the towel.We thought much more economical to throw them in out heat pump dryer for 15 minutes at the most.
Still need convincing it worth putting in because i have 3 bathrooms so that's and extra 3+K.

Also one hydronic guy told me it costs the same as central heating to run is this true?

Love hydronic heating seen it in action in Europe but they have it on 24/7 and walk around in undies/t-shirt its that hot indoors.

mixo