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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7919
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a Weil McLain CGt-5-PIN boiler with waterless hot water

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I have a Weil McLain CGt-5-PIN boiler with waterless hot water heater with hot water baseboards. I only get almost luke warm water for showers with an occasional minute of nice warm/hot water. Also water drips out of a verticle tube(about 4 cups a day)

Phil :

All work to be done by licensed professional. WE KEEP GOING UNTIL YOU HAVE THE INFORMATION YOU NEED, I come and go. This is step ONE.

Phil :

Hello

Phil :

Please look at this link, and confirm this is the boiler you have or not. Thanks

Phil :

Tell me if the base board heat works or not.

Phil :

and tell me if you can about how old the boiler is

Phil :

We can go from there until the situation resolves

Phil :

Phil

Customer:

This is the exact boiler. The base board heat works. I just bought the house from an estate sale so information is fleeting, but best I can figure is 4 yrs old

Phil :

Hello again,

Customer:

hello

Phil :

If the vertical tube comes from the boiler it is the pressure relief valve that is leaking, it has a floppy handle hanging from the top of it in most cases

Customer:

yes. this is what is happening.

Phil :

that is the manual release lever... put a bucket under the tube and trip the handle about 20 times, that will bounce the valve seat up and down and re-seat the valve in many cases.. if that fails the valve should be replaced

Customer:

ok. i will go try now

Phil :

Next we need to test the hot water flow rate in order to assess any water scale in the heat exchanger

Phil :

Fill a one gallon jug from the kitchen hot water tap wide open, and again from the cold water tap and tell me how long each took in seconds

Phil :

we can go from there.

Phil :

Phil

Customer:

I check a couple of times and it appears to be 53 seconds for cold water and the same for hot water

Customer:

that was the kitchen sink

Customer:

in the basement sink i got 15 seconds for cold and 48 seconds for hot

Customer:

is anyone ever going to answer back. its been 2 days

Phil :

Hello again. the just answer servers have been down, all day yesterday...and about half of today so far.... hopefully they are fixed now...

Phil :

I will do my best through all this.

Phil :

Did the water quit dripping from the pressure relief valve when you lifted the relief valve handle and then let go of it, so the valve snapped back shut? That will often re-seat the valve and stop the leaking.

Phil :

Thanks for doing the flow rate tests...

Phil :

from those tests it appears the heat exchanger for domestic hot water is OK and not clogged with water scale. (mineral deposits).

Phil :

See page 23 of the manual, tell me if your system has three pumps or just one pump... the diagram on the left shows a pump on the boiler and additional pumps for the radiant heat and another one for the domestic hot water.

Phil :

the diagram on the right shows just one pump, and thats on the boiler. I suspect that is what you have. zone valve #5 controls the flow of boiler water to the domestic hot water heat exchanger... that valve is controlled by a thermostat (not shown in the drawing) the lets the boiler water heat the domestic hot water... that thermostat or its sensor is going bad.

Phil :

Let me know what you find on your end.

Phil :

We can go from there

Phil :

thats the link again in case you need it

Phil :

Phil

Phil and other HVAC Specialists are ready to help you
Customer: replied 5 years ago.
I am a newbie to this house stuff so here goes. Their is one thing on my boiler labeled a circulator. Their is three zone valves. Upstairs their is three seperate thermostats
Thanks, XXXXX XXXXX the system piped that way with one pump works is that hot water is pumped around the hot water piping loop, see the diagram on page 23 of the link I posted.

when a room thermostat calls for heat the valve for that radiator or set of radiators opens, and lets hot water into the loop.

and the radiator gets hot... things that will prevent that is air in the radiators, or water pressure below 15 or 20 psig depending on how tall the building is.

all that apparently works.

it is just the domestic hot water heater, heated by the boiler hot water loop that doesn't work properly.. it has a similar valve and thermostat that regulates the hot water feed to the domestic hot water unit... tell me if you can find that.... it is shown on the diagram on page 23 with only one pump on the right.

that valve has wires attached, those go to the thermostat that controls the valve.. that thermostat has a sensing element attached that goes to the domestic hot water tank. it is that sensor that is likely going bad.


Look that over, we can go from there... none of this is effortless by the way, the college course on these skill sets takes 2 years, then to get good at working on these systems takes another 5 or 10 years of practice.

so be patient with yourself, study the manual I sent and page 23 until you figure out which is which on your system

we can go from there'

Phil




Customer: replied 5 years ago.
all i seem to be able to find is something labeled a low limit thermostat on tankless heater
Customer: replied 5 years ago.
all i seem to be able to find is something labeled a low limit thermostat on tankless heater. also a high limit
Good work.

Tell me where the low limit thermostat is set.. and if there is a 'differential' or DIFF setting on it, and where that is set.

Tell me what settings are available the high limit, and where it is set

we can go from there

Phil
Customer: replied 5 years ago.
Low has no diff. set at 190. high set at 210
The 190 to 210F settings, are settings you see on *high temperature safety cut out switches....if that switch is marked low limit then someone has been messing with it. or the covers on the the thermostats have been switched.


the hot water temperature controls are set between 120 and 150F at the highest.

Boiler work takes about 2 years of community college courses as an entry point, and a few years practice in the field as an apprentice.. none of these adjustments can be a fix..they all have to work together and the person adjusting them needs to be able to identify each control device, then adjust accordingly..then use instruments to verify how it all operates.

Tell me what city you are in or nearest and I will see if I can find a Weil McLain dealer in your area

Phil




Customer: replied 5 years ago.
franklin ma
Weil-Mc Lain XXXXX# XXXXX Milford, MA (NNN) NNN-NNNN‎ · weil-mclain.com
"Weil-McLain is a leading designer, manufacturer and marketer of gas- and oil-fired hot water and steam boilers for space heating in residential ..." - weil-mclain.com

you are fortunate, this appears to be the regional dealer.. call them and ask about service, they are about 7 miles away.


Let me kmow how it goes, Phil
Customer: replied 5 years ago.
thanks.