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
Hot water high limit setting
We get a lot of posts about HW boilers cycling and/or the building not making temp. Frequently they have the HL set at 160, 170,180.
This is too low. back in the 50s and 60 many MFGs designed systems that needed 200 degree water. Read some of the old books like the "Taco guide for hydronic Engineers" they promoted higher temps back then.
Yes, I am fully aware that the lower water temp you run the more fuel you will save. But you have to live with the system you have.
The boiler and the baseboard have to reach equilibrium and the HL needs to be set above this equilibrium temperature if it safely can be to keep the burner on.
Yes, if the boiler is massively oversized compared to the radiation the boiler will cycle. cycle on HL.Longer run times especially with oil promotes better combustion and less wear and tear on the burner.
The high limit is just the high limit. The thermostat and the baseboard run the show.
If you set the high limit higher its not operating the boiler at that temperature it will only get to the HL temp if it needs to to heat the system.
You would be surprised how many people think HW will boil if you go over 212 degrees. It won't the boiler is under 15 psi pressure.
And don't forget a 180 HL setting only gives you a baseboard temp average of 170 deg.
This is too low. back in the 50s and 60 many MFGs designed systems that needed 200 degree water. Read some of the old books like the "Taco guide for hydronic Engineers" they promoted higher temps back then.
Yes, I am fully aware that the lower water temp you run the more fuel you will save. But you have to live with the system you have.
The boiler and the baseboard have to reach equilibrium and the HL needs to be set above this equilibrium temperature if it safely can be to keep the burner on.
Yes, if the boiler is massively oversized compared to the radiation the boiler will cycle. cycle on HL.Longer run times especially with oil promotes better combustion and less wear and tear on the burner.
The high limit is just the high limit. The thermostat and the baseboard run the show.
If you set the high limit higher its not operating the boiler at that temperature it will only get to the HL temp if it needs to to heat the system.
You would be surprised how many people think HW will boil if you go over 212 degrees. It won't the boiler is under 15 psi pressure.
And don't forget a 180 HL setting only gives you a baseboard temp average of 170 deg.
Re: Varivalve heatimer clogging
We've had horrible experiences with hundreds of Vari-valves. The bellows disconnects from its top mounting causing the pin to fall into the orifice closing it forever. Of several hundred we installed in one year some 20 years ago, perhaps 20% failed in the first year and another 20% over the following years. Heat-timer wouldn't even discuss the problem, no less make good on their flawed product.
Put a Gorton C or D vent on it and be done with it all.
Put a Gorton C or D vent on it and be done with it all.
Re: How small can you go for a steam boiler?
I might add -- as a VERY general comment, not confined to heating at all, but applying to life in general -- doing the right thing for the wrong reason is never defensible; nor is doing the wrong thing for the right reason. The general rubric is "the end never justifies the means". Each action must be justified on its own merits.
Also a wildly unpopular opinion these days.
Also a wildly unpopular opinion these days.
Re: Another discussion about steam boiler sizing
I love reading these stories of guys that will experiment with their heating systems just to see what they can do or what they can accomplish. Since the company I worked only did schools, hospitals and industrial steam, with pressures to 300 psi and inputs up to 30,000,000 btu's I have little experience working or sizing residential systems. That said, I can tell you guys what an undersized steam boiler will do in a large building like a nursing home that has no control valves on the radiation. The job consisted of 2 low pressure steam boilers that the heating engineer undersized due to his stupidity. I started these 2 units and adjusted the input to 100%. With the outside temp at 30F, 1 boiler running all day would not heat all the building. All the radiation on the outside perimeter of the building and being the furthest from the boiler never even got warm and the radiation closest to the boiler room overheated. The steam only heated the radiators until it was exhausted and condensed with no more steam for the rest of the radiation. The only way that building would get warm was to run both boilers all the time or at least until they caught up with the steam load. Of course, there is much more to my story but you get the picture.
Re: Commercial water heating, storage tank vs indirect
Hi, As a very general rule, anything that has storage will give less temperature fluctuation than any sort of on demand approach... assuming the storage is correctly sized for the load. This matters for showers, where people will feel a one degree change, less so for other uses. Not sure that's what you were asking about though 
Yours, Larry
Yours, Larry
Re: Commercial water heating, storage tank vs indirect
$$$
indirect tanks with a coil inside more expensive to manufacture
indirect tanks with a coil inside more expensive to manufacture
hot_rod
2
Re: Energy Kinetics and Ecobee not getting up to temperature
Thank you for your post, @mad_hat , and for everyone’s replies.
Turn on SmartBoost per the link below.
Your manager controls the temperature, and you Hydrostat (DualGard) is only a safety, and should be set at 205/215, not 190 or any other temperature.
If the burner ever turns off, then the boiler has more capacity than your baseboard can emit; look for this.
If the burner ever turns off, then the boiler has more capacity than your baseboard can emit; look for this.
Also check to see if the Ecobee thermostat light on the left side of the manager ever turns off; if it turns off, then we’ll have to figure out why.
PM me with you installation company name and location and we can coordinate with them as well.
Thank you,
Roger
Roger
Roger
3
Re: Boiler temp question
What you are describing is normal. Remember that with the system pressurized, the boiling point is much higher than 212°F.
Automobile engine cooling systems are pressurized to 15 psi and will not boil unless they exceed 260°F.
Automobile engine cooling systems are pressurized to 15 psi and will not boil unless they exceed 260°F.
bburd
1
Re: Sanden SanCO2 HPWH, adding WiFi controller
It may not be completely obvious, but... wi-fi standards (frequencies, band widths, etc.) are not universally standardized. We here in the US may think they are, but... they aren't. Canada is the only other country in the world which uses the North American standard. Nor, for that matter, are cell phones necessarily. That may be why they haven't got a US model.
Re: Sanden SanCO2 HPWH, adding WiFi controller
I have a resistor I could send you that can be wired to with a switch that spoofs a low tank sensor to the controller starting a heating cycle. I understand you're looking for a wireless option but there is no modbus connection I know of on our models to connect to, even if the wifi module worked with or 60hz mains.
Teemok
1