Heat Transfer Kit

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PANiCnz

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#214861 31-May-2017 19:45

I need some advice on whether to get a 1 room or multi room heat transfer kit.

We've just had a new fireplace installed and its going great. We're now in a position where we'd like to distribute some of the warm air to the rest of the house. After some research I have settled on the Heat Trans brand from Bunnings, but am unsure whether to go with a 1 room or multi room kit. Ideally I'd like to go for a full heat recovery ventilation system but at this stage the cost is prohibitive compared with the cost of a heat transfer kit.

All three bedroom are at one end of the house (see floor plan below) and the doors for each room open on to the hallway very near each other, with this in mind the fireplace installer suggested we go with a one room transfer kit that comes out at the bedroom end of the hallway rather than a multi room kit into each of the bedrooms. The theory being that the extra ducting used in the larger multi room kits would lead to greater heat loss (1/3 degree per metre is my understanding).

Can anyone fault this logic?

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#1792566 31-May-2017 20:06

why not suck the cold air from the bedrooms back into the area where the fire is and allow the heat from the fire to make its way up the hall to the bedrooms? that way you dont really deal with heat loss from the ducting as much

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Aredwood

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#1792679 31-May-2017 21:59

Definitely better to directly heat the bedrooms rather than the hallway. You can always wrap more insulation around the ducting later if you are worried about that.

Make sure when room outlets are placed as far as possible from the doors to the hallway. And check that there is large enough gaps under the doors so air can easily return to the lounge when the doors are closed.

Dynamic

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#1793089 1-Jun-2017 13:46

Jase2985: why not suck the cold air from the bedrooms back into the area where the fire is and allow the heat from the fire to make its way up the hall to the bedrooms? that way you dont really deal with heat loss from the ducting as much

That is a simple but very smart idea.... we are thinking about heat transfer for home and have good access under the house.

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#1793151 1-Jun-2017 14:47

A problem with heading a bedroom directly is if it gets too hot (I hate sleeping in a too hot room; if that doesn't apply to you, disregard). The passive heat transfer systems are great, but you don't get particularly granular control. I guess you could install in-line dampers if it was a persistent problem.

solutionz

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#1793156 1-Jun-2017 14:55

Jase2985: why not suck the cold air from the bedrooms back into the area where the fire is and allow the heat from the fire to make its way up the hall to the bedrooms? that way you dont really deal with heat loss from the ducting as much

Mmmaybe... in theory...

But in practice (houses aren't air tight) you could also end up pulling cold air in from windows, bathroom vents etc.

Also you'd then need a floor mounted ventilation system in order to suck the cold air out of the bedrooms into the lounge... otherwise you risk just sucking any warm air in the rooms straight back out.

The other question is are you planning to leave the bedroom doors open at night? Else you may need to install a door grills etc - neither being good options in terms of noise.

We were in an almost identical situation at our previous house; fireplace didn't really reach the bedrooms.

I placed a massive 2kw+ panel heater on the wall near the rooms and that sorted them all out but had to sleep with the doors open - not ideal.

Ideal I would say is multi-room heat trans directly into each room - and add some extra insulation over the ducting if possible.

Ensure you get adjustable diffuses you can adjust for comfort in each room or "turn off" unused rooms for increased efficiency.

Ge0rge

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#1793157 1-Jun-2017 14:56

mdf:

A problem with heading a bedroom directly is if it gets too hot (I hate sleeping in a too hot room; if that doesn't apply to you, disregard). The passive heat transfer systems are great, but you don't get particularly granular control. I guess you could install in-line dampers if it was a persistent problem.

Having a well-sealed room could actually help in this instance - when the door is closed, it would effectively create an over-pressure in said room, preventing any more air from being blown in there and thus the temp should stay relatively stable.

snowfly

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#1793177 1-Jun-2017 15:14

Back in Easter I helped install a heat transfer system at our bach near Taupo, 4 bedroom with an outlet in each.

HeatTrans system (made by SimX), we purchased the 3 bedroom kit from bunnings (for the fan, controller and some ducts). Already had a spare outlet for 4th bedroom, and purchase a Y splitter.
Also purchased via our sparky R1.0 insulated ducting (200mm to fan, and 150mm to rooms), as the standard ducts in kits is only R0.6, and our bach is near Taupo so can get quite cold and wanted to minimise heat loss in ducts.

For reference, the R0.6 ducts have approx 30mm insulation around them, and the R1.0 ducts have approx 70mm, big difference.

We put the inlet in lounge in the opposite corner in the room from fire (to help make duct run shorter, and its recommended to put inlet a couple of meters away from fire flu).
Ran 6m 200mm from inlet to the fan unit, then 3m 200mm duct from fan to 3 way splitter.

The furthest bedroom was the master, at approx 19m from inlet to outlet. (the manual says recommended max duct run is 21m)
The other 3 bedrooms had approx 15m from inlet to outlet.

As mentioned above, we put the outlets in the far corner of each bedroom away from the doors, so the 'warm' air can pass through the room back to the door, and circulate back to lounge.

End result, we are very happy, and has spread the heat around the house very well, especially with 2 kids under 5, keeping their rooms room in the evenings.
Glad we upgraded to R1.0
When closing the lounge doors you can feel the large amount of 'return' air coming back from the rest of the house (bedrooms), enough to keep the 2 doors slightly open.

Off topic, but we do have the following unused R0.6 ducts for sale (that we didn't use from the kit, as we upgraded to R1.0):

1 x 200mm 3m R0.6 insulated
3 x 150mm 3m R0.6 acoustic insulated

I can post a floor plan showing my duct layout if that helps?

Kickinbac

414 posts

Ultimate Geek

#1793208 1-Jun-2017 16:26

snowfly:

Back in Easter I helped install a heat transfer system at our bach near Taupo, 4 bedroom with an outlet in each.

HeatTrans system (made by SimX), we purchased the 3 bedroom kit from bunnings (for the fan, controller and some ducts). Already had a spare outlet for 4th bedroom, and purchase a Y splitter.
Also purchased via our sparky R1.0 insulated ducting (200mm to fan, and 150mm to rooms), as the standard ducts in kits is only R0.6, and our bach is near Taupo so can get quite cold and wanted to minimise heat loss in ducts.

For reference, the R0.6 ducts have approx 30mm insulation around them, and the R1.0 ducts have approx 70mm, big difference.

We put the inlet in lounge in the opposite corner in the room from fire (to help make duct run shorter, and its recommended to put inlet a couple of meters away from fire flu).
Ran 6m 200mm from inlet to the fan unit, then 3m 200mm duct from fan to 3 way splitter.

The furthest bedroom was the master, at approx 19m from inlet to outlet. (the manual says recommended max duct run is 21m)
The other 3 bedrooms had approx 15m from inlet to outlet.

As mentioned above, we put the outlets in the far corner of each bedroom away from the doors, so the 'warm' air can pass through the room back to the door, and circulate back to lounge.

End result, we are very happy, and has spread the heat around the house very well, especially with 2 kids under 5, keeping their rooms room in the evenings.
Glad we upgraded to R1.0
When closing the lounge doors you can feel the large amount of 'return' air coming back from the rest of the house (bedrooms), enough to keep the 2 doors slightly open.

Off topic, but we do have the following unused R0.6 ducts for sale (that we didn't use from the kit, as we upgraded to R1.0):

1 x 200mm 3m R0.6 insulated
3 x 150mm 3m R0.6 acoustic insulated
I can post a floor plan showing my duct layout if that helps?

I agree with Snowfly. Very good reply.

PANiCnz

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#1793892 2-Jun-2017 18:59

Thanks for the advice everyone, looks like a straightforward answer. Now just need to do it!

pjay

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#1793948 2-Jun-2017 20:09

I've just completed a single room HT unit in circumstances very similar to yours.

Fairly easy to self install as we are in an older fully insulated house with attic access.

I did not buy a commercial unit, rather took advice from mingfans in Auckland - they recommended 150mm fully insulated ducting and a fairly high air flow two stage fan - a hundred or so dearer all up vs the kitset units. WOW - you need about 500mm clearances about the inlet and outlet to clear the ducting as it rises vertically from the ceiling mounts - if this is a problem you could fit a right angle bend I guess.

Like your thinking, I located the outlet at the end of the hallway adjacent to the doors to two bedrooms - these are at the south end of the house and fairly cold throughout the daytime and of course, in the early hours of the morning. The inlet is directly over the log fire and controlled by a thermostat.

In operation, it is very effective in removing the "steely cold" from the bedrooms - I liken it to having say a 2KW heater in the hall (which we used to have) - you can't romp around in the nuddy but its a hell'uva lot better than no heating, and doesn't cost.

We leave all the doors open to provide for a return path for the airflow (it is significant) - I have heard, that one can end up starving the fire of its air, and with a gas heater, the flame has been known to be pulled out into the room. There is an unintended benefit in that the lounge does not become stiflingly warm although I still sleep in front of the telly like most old farts my age!

My system is noisy - this is caused by air-turbulence in the ducting. I could lower the fan speed but one must drive the air into the rooms to make the difference felt. I will be fitting an air muffler later on.

Hope this helps - PM me if I can help further.

Amosnz

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#1793954 2-Jun-2017 20:15

When we put in our ventilation system I purchased some rolls of ADW 50 (R1.2) http://www.autexindustries.com/assets/Uploads/documents/GS-NZ-DS-ADW-Datasheet-web.pdf that I was intending to wrap around the R0.6 insulated ducting.

Unfortunately I never got around to it so I dont know what the benefit actually is, but more insulation must be better.

Speedtest

PANiCnz

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#1794017 2-Jun-2017 22:55

pjay:

I've just completed a single room HT unit in circumstances very similar to yours.

Fairly easy to self install as we are in an older fully insulated house with attic access.

I did not buy a commercial unit, rather took advice from mingfans in Auckland - they recommended 150mm fully insulated ducting and a fairly high air flow two stage fan - a hundred or so dearer all up vs the kitset units. WOW - you need about 500mm clearances about the inlet and outlet to clear the ducting as it rises vertically from the ceiling mounts - if this is a problem you could fit a right angle bend I guess.

Like your thinking, I located the outlet at the end of the hallway adjacent to the doors to two bedrooms - these are at the south end of the house and fairly cold throughout the daytime and of course, in the early hours of the morning. The inlet is directly over the log fire and controlled by a thermostat.

In operation, it is very effective in removing the "steely cold" from the bedrooms - I liken it to having say a 2KW heater in the hall (which we used to have) - you can't romp around in the nuddy but its a hell'uva lot better than no heating, and doesn't cost.

We leave all the doors open to provide for a return path for the airflow (it is significant) - I have heard, that one can end up starving the fire of its air, and with a gas heater, the flame has been known to be pulled out into the room. There is an unintended benefit in that the lounge does not become stiflingly warm although I still sleep in front of the telly like most old farts my age!

My system is noisy - this is caused by air-turbulence in the ducting. I could lower the fan speed but one must drive the air into the rooms to make the difference felt. I will be fitting an air muffler later on.

Hope this helps - PM me if I can help further.

PJ

What was your logic for installing the outlet/vent in the hallway rather than individual outlets in each bedroom?

raytaylor

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#1794772 5-Jun-2017 09:34

Installing in each room can be a problem due to fan noise if someone is trying to sleep.

When I was young, me and my father made a system for our house in Upper Hutt using wide PVC pipe.

Air was sucked in above the fireplace into a pvc pipe, which went through the attic and down into the closet in each bedroom, then out a vent beside the closet door if there was space, or in the closet if there was not enough space.

I remember us pre-wrapping most of the pipe in pink batts and using large rubber gloves to handle it.

The system I feel worked really well because warm air was blown out at the floor rather than a vent in the roof, so the cool air at the floor was forcibly heated, rather than hanging about the ceiling.

It was boosted the following winter with fans at each vent outlet to give some extra sucking power, and the main fan was removed. That way specific rooms could be heated, and others not.

Ray Taylor

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#1794790 5-Jun-2017 10:08

I wonder if there can be a feature to bookmark threads or even pages in long threads for things like this - won't need it ever but hey if i do need one in the future I usually never find the post by searching.

PANiCnz

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#1794981 5-Jun-2017 17:21

I purchased the three bedroom kit on Saturday morning and installed it across Sunday and today. Some initial thoughts after having it running for about an hour:

There is some minimal noise in the lounge from the vent above the fire which i suspect will be drowned out by the TV etc. More importantly the bedrooms are near silent, all with the fan on high speed.
The thermostat in the touch screen controller doesn't seem to be particularly well calibrated out of the box, but the instructions do provide guidance on adjusting the temperature reading to be more accurate.
We weren't able to install the third bedroom at the end of the hallway as the ducting provided wasn't long enough, the six metre's provided in the single room kit defiantly would not have been long enough
The two bedrooms where the vents are installed do feel a degree or two warmer than the hallway after running the fan for about an hour. We've got a HeaterMate in the hallway but the temperature reading on that hasn't yet moved.

I am planning to buy a couple of cheap thermometer's during the week and stick them in various locations around the house to see what sort of temperatures are being achieved. I visited my parents for dinner last night and stuck a thermometer on the ceiling near their fire place and it peaked at around 42 degree with the fire place cranked up.

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