Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.
If our community has helped you, please consider making a contribution to support this website. Thanks!
Best Of
Re: Tie two programmable thermostats in parallel to tie two heat zones together
Eric, your are correct as it relates to a sensor for the low loss header - by 100E I am referring to the 100 family of boilers. E indicates the current control platform - there are (6) boilers in 100E family (2 Kombis (KE) and 4 Heat Boilers (HE). The 100 is Viessmann's "base" model for wall hung modulating condensing boilers. I hate that term because the 100E family does a lot; that being said, the 200E does more (and you pay more for it...)
Your thought process is good, but the value of zoning is just that. If your goal is to prevent the boiler from tripping the high limit (and that's a good goal - this should not be a regular event) I would go to weather compensated operation: The boiler will have to be recommissioned (not a difficult process) and you'll need the outdoor sensor install (it comes with the boiler) Make sure it is installed on the North or North West wall. Be sure it's away from things like dryer vents, etc (anything that can skew it's accurate temperature sensing). Set a curve with a high limit under 180 (the curves are adjustable so you can fine tune as you go). Check out Viessmann North America YouTube and search for heating curves - you'll find some well done short videos.
I believe you posted a picture on another thread - it's a very nice job. The pipe work is clean and well done. That being said, I think the boiler is oversized. From the picture, there are 3 3/4" loops on the heating side - 199,000 btus is a lot to unload into that system (The only way to know for sure is an accurate heatloss). One of the features of the 100E is the ability to derate the boiler on the heating side; I have mixed feelings on this - the boiler should be sized by way of the heatloss; but look at your Installation and Service Manual page 63 - System Configuration/Boiler Address 596.0. The proper derate would of course be based on an accurate heatloss, which would have made this suggestion unnecessary. It's a way to get a little closer to a load match.
Your thought process is good, but the value of zoning is just that. If your goal is to prevent the boiler from tripping the high limit (and that's a good goal - this should not be a regular event) I would go to weather compensated operation: The boiler will have to be recommissioned (not a difficult process) and you'll need the outdoor sensor install (it comes with the boiler) Make sure it is installed on the North or North West wall. Be sure it's away from things like dryer vents, etc (anything that can skew it's accurate temperature sensing). Set a curve with a high limit under 180 (the curves are adjustable so you can fine tune as you go). Check out Viessmann North America YouTube and search for heating curves - you'll find some well done short videos.
I believe you posted a picture on another thread - it's a very nice job. The pipe work is clean and well done. That being said, I think the boiler is oversized. From the picture, there are 3 3/4" loops on the heating side - 199,000 btus is a lot to unload into that system (The only way to know for sure is an accurate heatloss). One of the features of the 100E is the ability to derate the boiler on the heating side; I have mixed feelings on this - the boiler should be sized by way of the heatloss; but look at your Installation and Service Manual page 63 - System Configuration/Boiler Address 596.0. The proper derate would of course be based on an accurate heatloss, which would have made this suggestion unnecessary. It's a way to get a little closer to a load match.
Redbaran
1
Re: Tie two programmable thermostats in parallel to tie two heat zones together
Somewhere there must have been a crossed wire -- in communication, not your wiring (at least not yet)..
A thermostat -- or at least the red and white wires -- is a switch. Nothing but a switch -- no power is supplied by the thermostat to anything -- it's just turned on or off. It is either open (no call for heat) or closed (call for heat). There is absolutely no reason why two thermostats can't be paralleled to the same relay coil. Now if the thermostats are also powered -- that infamous C wire -- they must be carefully wired to that transformer so that they really are all in parallel. But if they are self powered (such as batteries) there shouldn't be a problem.
Wired properly, the relay won't get twice the signal -- it will just see a closed switch through one or the other or both, as the case may be.
A thermostat -- or at least the red and white wires -- is a switch. Nothing but a switch -- no power is supplied by the thermostat to anything -- it's just turned on or off. It is either open (no call for heat) or closed (call for heat). There is absolutely no reason why two thermostats can't be paralleled to the same relay coil. Now if the thermostats are also powered -- that infamous C wire -- they must be carefully wired to that transformer so that they really are all in parallel. But if they are self powered (such as batteries) there shouldn't be a problem.
Wired properly, the relay won't get twice the signal -- it will just see a closed switch through one or the other or both, as the case may be.
Re: Intermittent pilot ignition control - replacing cable/wires?
If you take a jumper and ground the combination ignition/sense wire it will do the same thing as unplugging it, it will disrupt the flame rectification signal and the control shouldn't open the main valve at startup and it should shut down the main valve if you ground it with the burner firing.
mattmia2
1
Re: Steam heat system fitting
I’ve seen this in an old book. Can’t recall which one. It’s a specialty tee that allows the steam to go to two floors. The object was to lessen the amount of returning condensate in either riser from the tee.
An Important Skill for Teaching Tradespeople
An Important Skill for Teaching Tradespeople
Props can come in handy when you're trying to explain mechanical concepts.
Re: Help draining a old steel expansion tank.
So I just read an article about NOT having auto air bleeders on a system using a bladerless tank. I DO have one of those on a high point of the boiler a little before the return. Is this the cause of my issue?Yes. You do NOT want to bleed air out of the system at the radiators. You want the Airtrol funnelling the air back to the tank. Your auto bleeder will eventually bleed all the air out of the system and make the expansion tank get waterlogged, just like you now have.
jesmed1
2
Re: This a bull head t?
The vents are in the second pic. Two radiator traps are piped between the ends of the steam mains and the dry return. We call these "crossover traps" since they route air from the steam mains into the dry return. The large device in that pic is a "vent trap" which may or may not have a vacuum check screwed into the top- this is where the air actually leaves the system. From what I can see this is probably a Dunham Vapor system.
Re: LG Red HeatPump (ducted) energy consumption
I was just going to say, there is no heat strip, this is strictly condenser (inverter) outside and air handler in the attic. I have a back up gas boiler with forced hot water baseboards as back up... this system (ac and heat) runs independently from my gas boiler.
MattT
1
Re: LG Red HeatPump (ducted) energy consumption
Good question. It's just in the LG thinkq app. At first I thought maybe the app was wrong, so I waited the month and the electric bill confirmed my suspicion, so it seems accurate however it's reading it
MattT
1
Re: Should I install an Outside Air Thermostat for Viessmann Vitodens 100 B1HE-199?
Eric, thanks. It's difficult to define "normal" cycles; the easy answer is: "it depends". Heat Loss of the building changes as it gets colder out. Your system is zoned with DHW so there are a number of possible combinations of demands on the boilers from 1 to several. By lowering the operating temperature, you are more or less proving that an outdoor reset curve will work. Your process is essentially finding the correct boiler temperature for a given outdoor temperature. Going out on a limb here, I think your boiler is probably a bit oversized to the load; an accurate heatloss will tell the tale for sure. If you find that your boiler can heat the house at say 150 when it's 40 outside and you have to go to say 170 when it's 20 outside you have essentially found 2 points on a heating curve that will define an effective curve for your home. Don't get too hung up on how often the boiler is cycling. Just know that longer circulator run times with the lowest temperature water that will keep your house comfortable (comfortable is personal - we are all different) will reduce cycle compared to a high fixed setpoint whenever a themostat calls on the boiler.
Redbaran
2