Aquastat

MSDurica

I recently removed my domestic hot water from my New Yorker boiler and added a direct vent hot water tank. Do I have to change anything on the aqua stat?

Jamie Hall

Is this a steam or hot water boiler? If it is steam, you don't need the aquastat any more, but exactly how you take it out of the control system depends on how it's wired. If it's wired in parallel with the thermostat which otherwise controls the boiler, you can just disconnect it. If it's hot water, it may or may not be the only aquastat controlling the boiler, and what you do with it depends on whether it is or not.

MSDurica

MSDurica

Thanks, I believe it is the only Aquastat.

STEVEusaPA

You should replace the aquastat with a modern one like a Hydrostat, and turn off domestic (low limit).
Now that you have a cold start boiler, you'll want to protect the boiler from low temperature return water.
You'll now be able to use circulator hold off, and changing the well will also allow you to enable a low water cut-off-to protect the boiler from dry firing.
Also, unless your power is off, your primary control isn't wired correctly.

HVACNUT

It looks like an oil to gas conversion.

Agree with @STEVEusaPA . Look at the Hydrostat 3250 Plus.

For a steel boiler, that's not half bad. Horizontal tube, 3 pass, wet leg.
I'm not positive but I think New Yorker is an offspring of U.S. Boiler. And U.S. Boiler doesn't like conversion burners in their oil boilers for some reason. Lawyer stuff I guess. If that means anything to you.

Can I ask why you opted for a direct fired water heater vs. an indirect?

mattmia2

HVACNUT said:

Can I ask why you opted for a direct fired water heater vs. an indirect?

Also my question.

Might want to cap the tankless so if the coil ever fails it doesn't flood the basement.

EDIT:
Don't plug the ports unless you plug them with a relief valve. It is a sealed, heated vessel, it needs a relief to keep it from overpressurizing if the burner control fails to shut off.

EBEBRATT-Ed

@MSDurica

You cannot disconnect the low limit aqustat it is built into the control. You can replace it with a modern aqustat or set the low limit to it's lowest setting

STEVEusaPA

mattmia2 said:

...Might want to cap the tankless so if the coil ever fails it doesn't flood the basement.

Not allowed per code.

EBEBRATT-Ed said:

...set the low limit to it's lowest setting

Only if the boiler is piped to protect it from low temperature return water.

MSDurica

I went with the direct vent water heater due to budget.

MSDurica

Also plunged the ports.

MSDurica

Are there any instruction on how to go from an aqua stat to a Hydrostat

HVACNUT

> @MSDurica said:
> I went with the direct vent water heater due to budget.

You don't show the boiler piping but I wouldn't think the total cost of a properly installed indirect would be out of the ballpark. But that's another subject.

HVACNUT

> @MSDurica said:
> Also plunged the ports.

It was posted that plugging the ports is against code.

But it's done and the coil is still open to the atmosphere from the bull ports anyway. I hope.

HVACNUT

> @MSDurica said:
> Are there any instruction on how to go from an aqua stat to a Hydrostat

Yeah. Go back up☝️. I posted the I&O manual.

EdTheHeaterMan

Look at the white plastic block on the L8124 aquastat. Remove the blue wire from the upper right spade terminal. This will make the L8124 aquastat a cold start control (equal to the L8148 made by Honeywell with one exception).

Set the low limit to the lowest setting 120° with a 10° differential. Since the circulator will not operate until the boiler reaches the low limit temperature setting, you will want that as low as possible.

HVACNUT

> @EdTheHeaterMan said:
> Look at the white plastic block on the L8124 aquastat. Remove the blue wire from the upper right spade terminal. This will make the L8124 aquastat a cold start control (equal to the L8148 made by Honeywell with one exception).
>
> Set the low limit to the lowest setting 120° with a 10° differential. Since the circulator will not operate until the boiler reaches the low limit temperature setting, you will want that as low as possible.

Granted it's a steel boiler, but I would still want condensate protection.

MSDurica

HVACNUT - Do I leave the blue wire on to get condensate protection?

HVACNUT

Yes. Leave it. The boiler should maintain a minimum temperature of about 135°.

That's why the Hydrostat 3250 Plus is a superior control. You can have your cake and eat it too.

EdTheHeaterMan

the L8124 will do that. If you set the low limit at 140° the circulator will not operate until the boiler reaches 140° and stop when the boiler drops to 130°. This should keep you out of the flue gas condensation range.

By removing the blue wire, the burner will not operate if there is no call for heat. This will reduce fuel consumption

EdTheHeaterMan

Follow-up:
Agreed that the HydroStat control would be ideal since the manufacturer uses them on the current model of the same boiler. And certainly, we are not paying for the control so the advice does not cost us anything.

On the "Less Coil" option of the same boiler, they provided an L8148 control. when the electronic aquastats were introduced at a lower price than the old series 80 controls the replacement was L7248. both these controls have no low limit. if the manufacturer believes the cold start control is ok for the boiler less coil, then @MSDurica should be able to set up the control to be a cold start control.

Just sayin'

Here is an excerpt from the I/O manual from New Yorker on an older model FR series boiler:

3. On WATER BOILERS WITHOUT TANKLESS
HEATERS equipped with L7248 electronic***
aquastat controller, set High Limit (HL) at 180°F.
This temperature can be varied to suit installation
requirements. L7248 controller has the High Limit
adjustment range from 180°F to 240°F (82°C to
116°C). High Limit Differential is fixed at 15°F
(8°C).
4. On WATER BOILERS WITH TANKLESS
HEATERS equipped with L7224 electronic aquastat
controller, set operating control (low limit [LL])
at 190°F and high limit (HL) at 210°F. Operating
control (low limit) setting must be a minimum of
20°F below high limit setting.
L7224 controller has the High Limit adjustment
range from 130°F to 240°F (55°C to 116°C), and
the Low Limit adjustment range from 110°F to
220°F (43°C to 104°C). High Limit Differential is
fixed at 10°F (6°C), and Low Limit Differential has
adjustment range from 10°F (6°C) to 25°F (14°C).

*** no low limit on this control

EdTheHeaterMan

BTW: this ain't the first time we all disagree on this topic!

https://forum.heatinghelp.com/discussion/84513/bypassing-low-limit-switch-on-honeywell-l8124a-aquastat

and

https://forum.heatinghelp.com/discussion/123384/changeover-to-cold-start-boiler

STEVEusaPA

Who's disagreeing? Cold start with no protection to prevent condensing is bad. Either has to be done in the piping (best) or with the control. Boiler manufacture may provide a high limit only aquastat, which is fine, but always mention properly piping the boiler to protect from condensing.

Quoting George (the best in the biz IMHO) from the first thread you mentioned...
...Don't disconnect the wires in the control, in a liability matter it could make you responsible, FACT! I've seen lawsuits lost over less than that!...

This is why I recommended replacement which gives you some important extra features.

MSDurica

Edith heater man - do I set it at the lowest temp or 140?

STEVEusaPA

MSDurica said:

Edith heater man - do I set it at the lowest temp or 140?

Edith heater man LOL Ed's wife?
Do what I said in my first post, for the reason I mentioned in my last post.

EdTheHeaterMan

I would set it at the lowest setting, however several are concerned with condensation of flue gas because of low-temperature return water.

Your radiators will determine if you should keep the circulator off until the water temperature is at least 140°

What is your Peerless connected to? Cast Iron standing radiators? Copper tube w/Aluminum fin baseboard? Convectors on a Monoflo Tee system? This will determine how fast the return water reaches 130°. If it gets there quickly (less than 5 minutes) then 120° is my recommendation. If it takes 15 minutes or more then you will experience condensation of flue gases and the boiler might rust thru in 10 Years or so.

EdTheHeaterMan

Edith heater man LOL Ed's wife?
That is my brother's wife Archie Bunker Man

You Meathead!