Based on the 110-120 shoulder season recommended temps, it sounds like a condensing boiler. During the shoulder Seasons you will run into this problem , there are ways around it through programming depending on your boiler. However the mass of water in a condensing boiler is very small and not worth keeping that warm.
You could call them back and have them steepen the heating curve so when it gets a heating call , the boiler tries to bring the system temperature up more rapidly. Also maybe their sensors are on the boiler Loop and not on the system Loop. If if the boiler is basing its output on the system temperature rise it will ramp up faster while it monitors its own temperature rise.
(,Im assuming here that its piped and pressured correctly.)

Condensing boilers run better the colder the return water is so that way it's quite efficient. just throwing that out there.

If it's more a problem of ....it doesn't heat up fast enough ....then you may just end up losing the efficiency of the condensing boiler and having to give it a minimum set point of 150 160 so that that particular space will heat faster once the boiler fires, because at the higher Target temperature of the boiler will fire at a much higher rate.

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Normally:
The thermostat controls the circulator. When a call for heat is initialized by the thermostat, the aquastat should do one of a few things (if set up properly):
1. Hold off the circulator until the boiler temperature reaches the low limit setting-should be 140°, and fire the boiler.
2. If the boiler temp is between low limit and high limit, turn on circulator and fire boiler.
3. If boiler temp is above the high limit setting, turn on circulator and don't fire boiler.

In all scenarios, during a call for heat:
Circulator will run when boiler temp is between high and low limit.
Boiler will run when boiler temp is between high and low limit.

I imagine your settings are for the low limit, and they are wrong. You should have your aquastat set up for cold start, and hold off circulation when the boiler temp is below 140°.

You could also (or instead) use a mixing valve to protect your boiler from low temperature return water. Could be 3-way or 4-way. Circulator on the distribution side of the system will allow the circulator to constantly run during a call for heat, and the protection valve would slowly open (mix) hotter boiler water as it's temperature rises. Used with outdoor reset for some energy savings. But I wouldn't use it with deep set backs.

Keep in mind (associated with set backs & hydronic systems) getting 1 or maybe 2° per hour temperature rise is about as good as it gets unless you are running very (too) hot water temps and are oversized.

Edit: I based my opinions on a non-condensing boiler, which I think the OP has. But pictures, or make/model would help.

 

It is a non-condensing boiler. I don't have the model number available to me at the moment. STEVEusaPA, your post makes perfect sense and is how the system should work. The mistake in the setup appears to be that the aquastat doesn't hold off the circulator until temperature is met. The return water is piped directly into the boiler. I can see a mixing valve and/or outdoor reset could be of value.

Was one of my original concerns about thermal cycling the boiler to room temperature off base? Does it not matter any more?

 

...Was one of my original concerns about thermal cycling the boiler to room temperature off base? Does it not matter any more?

I'm not quite sure what you mean by a thermal cycle. In theory if the boiler was properly sized and had outdoor reset, and enough thermal mass, it would run 24-7, but that never happens.
If the boiler is set up correctly, it won't matter what temp the boiler is when it fires up, usually known as cold start. With the circ held off the boiler temp will rise pretty quickly to 140°+.
Boiler protection through piping is much better. With just using the aquastat to control the circ, you will see the circ cycling on and off frequently until the entire system starts getting and staying above 140°.

It's possible you just have an older style-triple aquastat. In which case the boiler will maintain temperature at the low limit setting (even if turned all the way down) all the time, but the control of the circ by the low limit only functions on a call for heat.
A more modern aquastat like a HydroLevel has a circulator hold off feature, and would work as you want it. Keep in mind if you upgrade the aquastat, you should upgrade the well and take advantage of the low water cut-off (unless you already have a separate one installed).

 

Simple fix is a mixing valve. 'Stat will still cycle the pump and boiler, but mixing valve will allow the boiler to run "in the zone" for longer periods of time an extend the life of the cast iron heat exchanger and the flue.

More elegant solution is out door reset that runs an injection pump. This will mean you have a minimum of three pumps, one injection, one boiler and one circulator for the emitters.

 

I'll speak to the service company about some changes. I appreciate all the help and suggestions. Thanks for taking the time.


The "thermal cycling" comment comes comes from an age-old belief that turning off your water heater or boiler during vacations causes premature failure because you're not suppose to let it cool off to room temperature. I think I heard that in the 1960s!

 

From what I've seen, stat calls, boiler fires, pump runs and yes, it does run cool for a while. Not long if baseboard, if big old radiators there should be a bypass or mixing valve to keep the temps up.

I grew up in a house with huge rads from an old gravity system. Except in bitter weather, we kept the boiler temp at 135°. It was a boiler that stayed hot and the pump cycled with the stat but knowing what I do now, we did run the sucker cool. The replacement was piped the same way but it started cold with a 180° limit. Probably didn't last long, folks moved out shortly after having it installed.

 

I've never seen one set up the way Steve describes it but I like that. Almost always, around here, its: call for heat, zone valve opens, pump runs, proof of flow, then boiler fires.

Anyhow, I do have one further comment and that is that you said in your original post that it calls for 110 to 120 degree water in the summer. And if that is a non condensing boiler that water is too cold. 80-90 returning.
So, were those factory suggestions (based on PS piping) and it didnt get piped right? Or installer suggestions and they're incorrect?

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The temperature suggestions appeared to be from from the original installer. My father would faithfully get his flashlight and make the change 4 times per year. I have to believe 99% of their customers never bothered. In the summer, the zone valves were closed, circulator never ran and the unit probably fired a few minutes per day. Why is 110-120 too cold?

 

Depends on the boiler, but you may see flue gas condensation and/or sooting. Usually a noncondensing boiler wants 130-140 return water. Thats why some mentioned the 3-way valve and bypass.
Heres a pic of too cold return water problems.

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You have a cold start boiler, very common around here. Saves on fuel.

Just have an outdoor reset installed, and you won't have to manually adjust the aquastat.

 

You have a cold start boiler, very common around here. Saves on fuel.
Just have an outdoor reset installed, and you won't have to manually adjust the aquastat.

The house is in PA. I'll be there in a month and will check things out. A new Hydrolevel and outdoor reset could really improve operation. I'll talk to the service guy once I get there.

 

Wow, that's a mess. How old do you think it is?