tekmar 363 and UNOCC

engrav

Bought a house with a tekmar 363. Has an installed switch for OCC and UNOCC. But when I put it on UNOCC the room temps do not change. (But DHW does go off).



I have all of the various numbers displayed by the 363 but not sure which are relevant to this question. Some are



I see

MIX ROOM Unocc 65

BOIL ROOM Unocc 65

DHW TANK UNOCC 80

SETPOINT Unocc off

WWSD Unocc 62



also

MIX ROOM Occ 70

MIX TERM base

MIX MIN 150

MIX INDR 100

MIX DSGN 220

OUT DSGN 32

MIX MAX off

MIXING flot

MOTR SPD 90

10K 2 DHW

BOIL ROOM occ 70

BOIL DSGN 200

BOIL MIN 180

BOIL MASS hevy

DHW THRU valv

DHW TANK occ 180

DHW PRI mix

SETPOINT occ 135

WWSD occ off



Have tried a couple of heating companies but neither seems masterful with the 363.



Have studied the data brochure but is rather beyond me at this point.



Thank you.

Zman

363

The 363 is not designed to setback room temps.

Those features are available in the TN4 and TN2 models.

Carl

engrav_2

tekmar 363 and UNOCC

thank you

still confused so

asked tekmar support who replied



Not quite... The tekmarNet 2 and 4 thermostats provide individual setback and if set correctly can group thermostats to setback; but when a timer is wired to the Unocc terminal and common the SYSTEM will setback to all the Unocc settings. That is the system will reduce the boiler-mix targets to the UnOcc temp and thus reduce the room (zones) temperature.



See page 5 of 40 of the 363 data brochure http://tekmarcontrols.com/images/_literature/363_d_06.pdf

Zman

Well

I think that is a bad idea on most systems.

If you lower the water temps to the point that the room temp is reduced, you will still have a call for heat and the boiler will be maintaining temp the entire time. I would bet that you will actually use more energy set up this way.

This may work for some constant circ systems but is a bad idea for the average residential system.

With TN2 and TN4 the setpoint to the room is lowered and the boiler temps are lowered. This is very different.

Carl

engrav_2

tekmar 363 and UNOCC

You may be right. It may be a dumb system for us since we are in the building intermittently. But the 363 is what we have and I am trying to understand it to see if we can use it in a manner more relevant to us. So first to understand UNOCC. And tekmar does say UNOCC will reduce water temp, will thus save energy, and the temps in the rooms will drop even if tstats are not changed.



So if UNOCC is not the way, and we have a 363, how can I use the 363 when we are not in the building to save energy?



Or should I just reduce the tstats?



thank you.

Zman

Boiler

What type of boiler do you have?

What type of heat?

engrav_2

tekmar 363 and UNOCC

When I return I will collect brands models and make a signature. Also will then be heating smarter. For now have a jpg of the boiler which uses oil. The adjacent boiler is not part of the house heating. House has several zones, one infloor and the others baseboard. In NW Washington so low temp is maybe 25 and high maybe 80. We are only in the building intermittently.

Zman

Details

I think your best approach will be to find a way to setback the thermostats when you will be away for long periods. Using the 363 to turn off the DHW will also help, the unocc wwsd setting will also help save energy.

You have a non condensing boiler. There are limits to how far you can safely turn it down.

There are some changes that could be made to your present setting that would help with efficiency. I would want to be a little more familiar with you setup before making suggestions.

 Carl

engrav_2

tekmar 363 and UNOCC

Thank you.



Ah ha. You recommend what I actually do. When we leave I set the OCC UNOCC switch to UNOCC and turn down the tstats. UNOCC sets DHW to 80 and invokes the UNOCC mixing heating curve.



Why don't I just do this and let that be that and move on? Tekmar and two contractors say no need to turn down the tstats, and if true would save a little diddling round. And, would be fun to understand this stuff. (am a newbie at 363)



But tekmar also says some of the UNOCC settings are a "misapplication" including

MIX INDR 100

MIX DSGN 220

OUT DSGN 32

MIX MAX off

BOIL DSGN 200



So I stumble on. I appreciate your comments. I do have a call in to a new "expert" recommended by tekmar so maybe more info will arrive.



If to max savings I must hit UNOCC AND reduce the 4 tstats, and can understand , that will be fine.



Thank you again.

Zman

Direction

I think there are quite a few settings that should be tweaked.

This woulds be better done by a tech on site that can verify the way your system is setup and piped.









MIX ROOM Unocc 65   Should be set to setback temp ( the temp you want the room during unocc)



BOIL ROOM Unocc 65  same as mix room



DHW TANK UNOCC 80   Why not off



SETPOINT Unocc off  



WWSD Unocc 62   this could be set lower (will turn off boiler based on outdoor temp)







also



MIX ROOM Occ 70   OK



MIX TERM base       I thought you had  infloor



MIX MIN 150           Seems high, usually more like 90 to110 depending on type



MIX INDR 100    Very high, should be more like 70



MIX DSGN 220   This is incorrect, should be in the 120 to 150 range, depending on type



OUT DSGN 32  should be design temp for your area



MIX MAX off     should be set



MIXING flot



MOTR SPD 90



10K 2 DHW



BOIL ROOM occ 70



BOIL DSGN 200     This is too high



BOIL MIN 180      This could go as low as 150 depending on needed output (will save energy)



BOIL MASS hevy



DHW THRU valv



DHW TANK occ 180   Way too high



DHW PRI mix



SETPOINT occ 135



WWSD occ off   I would turn this on and set to 65



Carl

engrav_2

tekmar 363 and UNOCC

nice, your recommendations and those of tekmar support in Canada are the same



in fact, you only seem to differ on whether or not it is Ok to use UNOCC to reduce water temp, leave the tstats the same, and let the room temps float down (of course with current settings they do not float down)



set by tech who can understand piping? yes, but cannot find one though third try has yet to call back (property is on an Whidbey Island and services are kinda skimpy)



infloor? living room is infloor, rest of house is baseboard (living room is an add-on)



tekmar support said making said changes should not hurt anything so if third tech try fails, I will do 'em myself



you have been helpful, email me your address, I will send a consultation fee

Zman

Setback

In theory doing the setback using water temp should work. You calculate the water temp needed to match the heat loss at a given indoor temp and you are good to go.



Here is my problem with it.

The boiler will be calling and hot anytime the outdoor temp is below the WWSD setpoint. Anytime the boiler is hot, you are wasting some heat and electricity.



The boiler and baseboard loop will have to remain above 150 supply to prevent boiler condensation. On warmer days the unocc heating curve will be lower than 150. The house will heat to the t-stat setpoint regardless.



A heat loss calc is an average estimation. On the average 25 degree day with overcast sky's and light wind, the estimate will be pretty close and the system will match the temp very closely.

On a calm 25 degree day with lot's of sunshine, the house will overheat.

On a super windy 25 degree night, There will not be enough heat.



If you decide to make the adjustments yourself, just go slow and record everything.

There are settings that will make the system nonfunctional if they are incorrect.

Tekmar has a job record sheet for most products that make the process easier.



Carl

engrav_2

tekmar 363 and UNOCC

Got it, thank you.

Still working on a trained person to come & fix.

Will post outcome when I have an outcome.