Two new videos this week The case for 2 psi and The case of the tripped limit controls

RayWohlfarth

Here are the links
https://youtube.com/watch?v=CvRxCrPwFWI

This is the one for 2 psi steam pressure
https://youtube.com/watch?v=ceSfgRt0jPc

retiredguy

These isolation valves were added to a hot water system after I retired and boy I bet that they save a ton of money. Ha,Ha. Some engineer thought that they had just saved us from running out of fuel, what a joke. If you are going to add a component make sure that you do all the "engineering" and not just spec a device. I guess that is why we have service techs that will finish the engineering design work.

RayWohlfarth

@retiredguy I never imagined it would keep heating the way it did.

JUGHNE

I had a large house with gravity piped system starting out at 2 times 3" supplies.

A lot of heat would be retained in the piping and CI boiler when tstat shut boiler and pump down.

Simple solution was a strap on aqua stat to hold the pump relay on until water cooled down, milking the residual heat out of basement pipes which are well insulated.

Somewhat like your time delay but simpler.

retiredguy

Back in the 1970's when I was still doing residential heating all pumped hot water systems had the pump controlled by an aquastat set at around 110 F. Back then almost all systems were piped with steel pipe and most radiation was cast iron.The pump ran any time the systems water temp was above that setting.

RayWohlfarth

@JUGHNE That was pretty common back then and simple solution. There is lots of heat left in those cold cast iron sectional boilers. I read about a solution @DanHolohan recommended when I had my old boiler and installed a time delay relay on my burner. On a call for heat, the burner would start about 10-15 minutes after the pump and in most instances, the burner never fired.
@retiredguy That wasn't efficiency I guess LOL
Have a good weekend gentlemen

Steamhead

RayWohlfarth said:

@JUGHNE That was pretty common back then and simple solution. There is lots of heat left in those cold cast iron sectional boilers. I read about a solution @DanHolohan recommended when I had my old boiler and installed a time delay relay on my burner. On a call for heat, the burner would start about 10-15 minutes after the pump and in most instances, the burner never fired.
@retiredguy That wasn't efficiency I guess LOL
Have a good weekend gentlemen

We had this happen too. Solution there was to replace the standard aquastat relay with a Beckett AquaSmart. Besides its 2012-compliant weather-responsive ("Heat Manager") features, the AquaSmart has a circulator-off delay option of up to 4 minutes 15 seconds, which when activated, keeps the circ going long enough to move the residual heat out to the system.

JUGHNE

The old CI boiler I spoke of was burner on pump relay on....burner off, pump off.

So pipe strap on aquastat was the simplest money.

This was replaced with Mod Con simply because the brick chimney was defunct.
No simple repair, liner or B vent possible or feasible.

Over the years with the modcon, the cleanings and repairs would almost wipe out that added maybe 10% of efficiency.

RayWohlfarth

@Steamhead I have never used one of those but have looked into using one. It seems like a nice control
@JUGHNE The mod cons do require more maintenance than a standard CI with a standing pilot. The customers dont understand that at all

jumper

Don't like to stop/start motors but heating fuel was less expensive then.

Steamhead

RayWohlfarth said:

@Steamhead I have never used one of those but have looked into using one. It seems like a nice control

Most of the ones that come on new boilers are Hydrolevel Hydrostats. These are also 2012-compliant, and we use them too, but they don't have the circ-off delay feature.