Hydronic/Boiler System Turn Down ??

Every year about now I turn off my NG boiler in my garage? Simply turn the breaker off and don’t flip it back on till fall.
Would simply being left on, be a good idea or not?
I’ve been in the habit of turning it down for the warmer months.
I’ve had it serviced last fall before turning it on.
If left on would it need servicing more often? I hadn’t serviced it in 4 years and it probably didn’t need it this time either.
The garage is well insulated, as my contractor said that the building is tight.
The only time the overhead is used is to allow my snowblower to escape when needed.
Other than that very seldom as the garage is used for projects not vehicles.
My buddies son leaves his on year around. The reason for that is due to it being controlled by a water heater which isn’t code today.
They are worried if it doesn’t start up a new boiler is in their future. $$$

Miss the Pontiacs said:

My buddies son leaves his on year around. The reason for that is due to it being controlled by a water heater which isn’t code today.

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This makes zero sense. The water heater is the boiler in this instance, and the tank burner will cycle on and off as needed.

As far as "code" is concerned, AFAIK, a water heater has never been classified as a boiler, at least as far as the residential style domestic water heater is concerned.

Additionally, people do not change the water heater T&P valve to one that is rated properly for boiler use, which is a bigger problem, IMHO.

If your boiler has a standing pilot, leaving it on can keep the spiders away.

Some circulator (pump) controllers have an exercise function, which will help keep the circulator from seizing due to a lack of use. Depending upon the size of it, it may not be too expensive to simply leave it on... or make up a timer control. Leaving the pump on can prevent pipe freezing if there's a cold snap after the system has been turned off and it is forgotten to turn it on for that day.

Otherwise, if there isn't a call for heat, it shouldn't operate, which means it is off. Killing the main power will just kill standby power usage by the board or 24v transformer.

I run my IBC boilers in the fall for a week and shut them off and heat things with my outdoor wood stove until spring when it gets too warm for the wood stove to run without turning into a creosote factory. At that point if I feel (let’s be honest here, if SWMBO feels) like we still need the heat on I’ll turn the boilers back on and let them provide heat. I will always run them at least a few days in the spring to make sure they’re still operational as they’re my backup heat source if the stove goes down for some reason. I’ve never had an issue with the boilers turning back on either spring or fall.

Zero reason to leave them powered up in my opinion. I flip breakers and walk away until fall.

An easy solution wood be to run the boilers weeks before you “need” them and you should have time to get someone out to service them if needed.

danski0224 said:

This makes zero sense. The water heater is the boiler in this instance, and the tank burner will cycle on and off as needed.

As far as "code" is concerned, AFAIK, a water heater has never been classified as a boiler, at least as far as the residential style domestic water heater is concerned.

Additionally, people do not change the water heater T&P valve to one that is rated properly for boiler use, which is a bigger problem, IMHO.

If your boiler has a standing pilot, leaving it on can keep the spiders away.

Some circulator (pump) controllers have an exercise function, which will help keep the circulator from seizing due to a lack of use. Depending upon the size of it, it may not be too expensive to simply leave it on... or make up a timer control. Leaving the pump on can prevent pipe freezing if there's a cold snap after the system has been turned off and it is forgotten to turn it on for that day.

Otherwise, if there isn't a call for heat, it shouldn't operate, which means it is off. Killing the main power will just kill standby power usage by the board or 24v transformer.

Click to expand...

Regarding the buddies son, his water heater may be indirect fired, meaning there is a heat exchanger in the water heater pulling heat from his hydronic boiler. If this is the case, his boiler needs to be on all the time.

That is how it was plumbed in my last house. Boiler was required to be operational year around, if you wanted hot water for showers, etc.

danski0224 said:

As far as "code" is concerned, AFAIK, a water heater has never been classified as a boiler, at least as far as the residential style domestic water heater is concerned.
Additionally, people do not change the water heater T&P valve to one that is rated properly for boiler use, which is a bigger problem, IMHO.
If your boiler has a standing pilot, leaving it on can keep the spiders away.
Some circulator (pump) controllers have an exercise function, which will help keep the circulator from seizing due to a lack of use. Depending upon the size of it, it may not be too expensive to simply leave it on... or make up a timer control. Leaving the pump on can prevent pipe freezing if there's a cold snap after the system has been turned off and it is forgotten to turn it on for that day.
Otherwise, if there isn't a call for heat, it shouldn't operate, which means it is off. Killing the main power will just kill standby power usage by the board or 24v transformer.

Click to expand...

Both my buddies son and my boiler systems are in a detached garage not our homes.
My system has been turned off about this time of year and turned back up in the fall. So not likely to have a freeze up situation as there is glycol in the tubing. So only used for heat and not required for heating water. I’d be more afraid of items in garage freezing and that would take some time.
When I turn it down both the 120 and 240 volt breakers are turned off.

jblnut said:

I run my IBC boilers in the fall for a week and shut them off and heat things with my outdoor wood stove until spring when it gets too warm for the wood stove to run without turning into a creosote factory. At that point if I feel (let’s be honest here, if SWMBO feels) like we still need the heat on I’ll turn the boilers back on and let them provide heat. I will always run them at least a few days in the spring to make sure they’re still operational as they’re my backup heat source if the stove goes down for some reason. I’ve never had an issue with the boilers turning back on either spring or fall.

Zero reason to leave them powered up in my opinion. I flip breakers and walk away until fall.

An easy solution wood be to run the boilers weeks before you “need” them and you should have time to get someone out to service them if needed.

Click to expand...

My boiler is also an IBC, my back up are the days when it the days hit a nice light jacket day outdoors and the door can be left open. Haven’t turned it down yet, but the days are getting warmer. My garage is R24 in the walls and 8” Styro on the roof. I did the insulating my self and carefully installed and sealed. Garage doors are R18 and fit snuggly.

I’ve seen a couple of examples of your heating system and if I was on the farm that would be my go to. Good job. I never really thought of a low smouldering fire causing creosote, interesting point.

I’m in your camp as to turning the system down when not required.

Funny story, but not really. I’m in the garage and it felt cool never gave it any mind and didn’t check it out. Got busy and forgot all about it. The next day it still felt cool. Found my thermostat batteries had given out. It was probably 25-30C outside, needless to say it took awhile to build up the heat sync in the slab. I keep it around 60F and depending on what I’m doing it can a bit much. But great for having a buddy over and enjoying a beer.

T444e said:

Regarding the buddies son, his water heater may be indirect fired, meaning there is a heat exchanger in the water heater pulling heat from his hydronic boiler. If this is the case, his boiler needs to be on all the time.

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That might be the reason. My buddy is a boiler maker and is out of town on jobs so I’ll have to quiz him next time he is home. His son bought the place with a detached garage and water heater setup. Water heaters may have been allowed in detached garages at one time but no longer. Maybe he is not using glycol and doesn’t want to take the chance. My contractor said he could setup my lake garage with a water heater setup, I’ll think I’ll pass. The gas inspector said I could use an on demand setup if I had a use for hot water by having a bathroom installed. So that won’t be happening at the lake but I had lines run in case I do a boiler setup which I’m thinking about but will have a NG blower at the minimum.

Torque&Recoil said:

That is how it was plumbed in my last house. Boiler was required to be operational year around, if you wanted hot water for showers, etc.

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In a house I totally agree. My application is a detached garage. My one neighbour or maybe it was his wife had a total reno of their house. They even did a portion of their driveway and piped that needed to be replaced. She thought she could free up some space until she found out that the ac needed to be dealt with. They also have a detached garage with a NG blower. Knowing her I thought they would tear up their garage floor and place tubing. They did do a chunk of driveway so why stop there.

I have an electric boiler, so different thought process vs. a gas boiler. I usually kill the 40A breaker on the boiler itself around this time of year, turn it back on sometime in September.

Two reasons I kill the breaker. First is so I don't hear the safety contactor buzz all summer. Second is a bit more complicated. In an effort to keep the water circulating periodically, I wired the fan control output on my Nest thermostat to kick on the system for 15 minutes per day. With a Taco SR501 pump controller, this turned on both the pump and the boiler. Obviously no need (or desire) for the boiler to heat in the summer.

I have since switched the pump relay over to a Tekmar 301P. This pump controller has both a post purge function (runs the pump a bit after the thermostat switches off) and a circulation function. With this new control, in theory I no longer need to kill the breaker during summer.

Turn it off at the breaker or at the disconnect. Unless you have a electronic thermostat that would need programing and possibly a new battery.
It would be a good idea to test glycol strength and might consider seeing if the glycol manufacture sells a inhibitor package to add. Propylene can turn acidic if it gets under30%.

I turn mine off at the disconnect. Have not done it yet this year as it's been abnormally cool and the same boiler has a zone inside the house that was actually kicking on some as late as last week.

My theory is it makes it less likely that a summer electrical storm will zap the boiler. Mines a fully condensing NG wall boiler that turned 20 this year. I mean, I don't guess I've had any other appliance destroyed by lightning in that time, so maybe my theory makes no sense? Seems like it would be easier on the controller to be off half the year.

At least it does force me to be intentional about starting it up for winter which gives me a chance to do preseason maintenance, clean out the combustion chamber, check the flue for blockages, check for CO, borrow a combustion analyzer and make sure it's running in spec, that sort of thing.

Thanks guys. Yesterday I turned off the breaker. Not a nice day here today but the slab retains the heat for a few days. Heading to the lake tomorrow and the forcast for next week improves.
I feel the boiler was a good investment the upfront costs were higher but the cost of using this type of heat for me is minimal.

I had a Taco pump fail. Not sure why it seized, as the setup is supposed to run the circulator occasionally.

finn said:

I had a Taco pump fail. Not sure why it seized, as the setup is supposed to run the circulator occasionally.

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if you turn the boiler off, it can't supply power to the circulator.

dscheidt said:

if you turn the boiler off, it can't supply power to the circulator.

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Or else unplug the circulator.

There are a couple of zones, so unplugging the circulator for one zone (primary / secondary loops) lets heat to continue, as long as the primary pump still functions. Actually, even with the primary pump disabled, the secondary pumps still allow circulation through the system, albeit not as efficiently.

The latest saga is that one of the oddball and obsolete Danfoss thermostats failed. New thermostats require the green wire, which the Danfoss did not, and the wire is buried in the wall, including a horizontal run, so it’s going to be difficult or impossible to pull a new wire. The wall is a kitchen addition, so the bottom plate is on top of the old rim joist, with little or no access if I have to drill new holes for snaking a new thermostat wire (if the old wire won’t pull a new, larger diameter wire).

I see a “what I did on my summer vacation” episode in my future

finn said:

Or else unplug the circulator.

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the thread is about depowering the boiler for the summer. One very good reason not to do that is because the boiler or its controller usually exercises the circulators by running them a couple minutes every so often. This really does help keep them from seizing.

finn said:

There are a couple of zones, so unplugging the circulator for one zone (primary / secondary loops) lets heat to continue, as long as the primary pump still functions. Actually, even with the primary pump disabled, the secondary pumps still allow circulation through the system, albeit not as efficiently.

The latest saga is that one of the oddball and obsolete Danfoss thermostats failed. New thermostats require the green wire, which the Danfoss did not, and the wire is buried in the wall, including a horizontal run, so it’s going to be difficult or impossible to pull a new wire. The wall is a kitchen addition, so the bottom plate is on top of the old rim joist, with little or no access if I have to drill new holes for snaking a new thermostat wire (if the old wire won’t pull a new, larger diameter wire).

I see a “what I did on my summer vacation” episode in my future

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There are lots of thermostats that work on two wire connections. You probably don't need to do construction....

dscheidt said:

the thread is about depowering the boiler for the summer. One very good reason not to do that is because the boiler or its controller usually exercises the circulators by running them a couple minutes every so often. This really does help keep them from seizing.




There are lots of thermostats that work on two wire connections. You probably don't need to do construction....

Click to expand...

Agree on keeping the system powered. I think my circulator seized because I was in the habit of powering the system down for the summer. That’s what I was trying to get across.

I’m looking at a Nest thermostat to match the other one in the house, and the Nest in the shop and the Nest in the Az house. One Ap for all the thermostats is the goal.

My hvac guy recommends I go with a three wire thermostat for battery life and reliability considerations. His experience says the two wire systems aren’t reliable. (Excepting the old Mercury switches, I suppose, but I’m not sure they’re even available anymore). Some Nest thermostats work without the green wire, but the documentation warns that they aren’t recommended for heat only systems. Don’t know why, though.