W-Mc GV prv issue

kpc_43

w/ a W-Mc Gold GV boiler PRV dripping constantly. I have replaced the extrol tank, shut of the water to the boiler, replaced the PRV.. still weeps. The indirect is only 8 yrs. old (SS-40). Pressure gauge reads 18-24 psi.
any thoughts?

tim smith

I am thinking 2 things, one is the gauge reading may be off, 2

is the expansion tank is undersized. Fire up boiler with fill valve off and watch pressure with a test gauge on boiler drain. I am suspecting that your pressure is rising to your relief setting and dripping then. If I don't have exact volume of system, I estimate what tank I might need and then choose next bigger. Most my old house systems get at least a # 60 extrol tank and some of the large house old converted gravity systems may get a vertical SX60V tank. My .02 worth today, Tim

kpc_43

good thoughts...

the old extrol was a #30 it was fine for 9 yrs.(house built in '99) New one same size. I suppose I should check the pressure on the new tank. Also there is 2 zones of onix radiant, ad a zone of fintube.It had glycol in it up untill 5 mo. agao. I flushed it out of the system due to som severe neglect.It now just has water in it.

Norm Harvey

Can you put a guage after the PRV to see what its set at, and adjust the static fill pressure down. I've enclosed a picture of the tee and ball valve set up you can use to install a guage.

The pressure relief valve isnt leaking coerrect? Your just showing a higher pressure than you want?

Is that high pressure reding when the boiler is at high limit, or cold?





To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mark Custis

Keep cleaning the system

Have you changed the PRV?

How did you flush the system?

What is the pressure on the tank?

I do not see the Onix as a problem, but who knows.

kpc_43

yes changed the

PRV. System was flushed out as if I was purging out the boiler. I did notice Muddy type water. I "presume " the tank pressure was @ 12 psi.... I need to check.

kpc_43

PRV is...

leaking. That is the problem. The pressure ga. reads 25 psi max....should not leak @ 25#. especially a new PRV.

Mark Custis

Norm is right

Add a new known gauge. PRVs are usually not wrong. Things do come bad out of the box.

Test test test, do not guess.

I get enough bad news without: home is launched to meet space station.

Steve M_2

Bad pump or thermostat?

The GV's have a primary pump that circulates within the primary loop of the boiler until a thermostat opens at 140 degrees and sends hot water to your load. The thermostat is just like the old ones they used to on cars and it's located at the black iron tee beneath the plug. The pump may be bad or the thermostat isn't opening causing overheating and pressure buildup. The plug can be very hard to remove, especially if no one removed it when it was new and teflon taped and doped it. I couldn't remove it once with another person and 2 48" pipe wrenches. I've cut the whole tee out before and installed a 3 way mixing valve in place of the thermostat when the HO didn't wanna replace the boiler.

The GV's aren't one of my favorite boilers and I've replaced plenty of them that were only 10 years old. IMHO a very poor design.

Steve M_2

pump or thermostat?

The GV has a built in primary pump that circulates within the boiler. When the temp hit's 140 a thermostat opens and lets hot water out to your load. The pump or thermostat may be bad causing overheating and pressure build up within the boiler. The thermostat is below the black iron plug at the tee and can be a bear to remove to access the thermostat. I couldn't remove it once with another guy and 2 48" pipe wrenches. I've cut out the whole assembly and installed a 3 way mixing valve in place of the thermostat once when the HO didn't wanna replace the boiler.

IMHO this boiler is a very poor design and you should offer an option of replacing it. Is it vented in stainless? If it's only 9 years old it prolly is. The early ones were speced out to vent in hi temp plastic that was all recalled. Good luck.

kpc_43

another good..

thought. I checked that and it appears to be working. Vent is pipied in SS. I realize this was not one of W-M best units. w/ the ultra out I don't know why they even keep it around.

tim smith

There is actualy a retro kit from w/m to replace that bypass

thermostat with just a few fittings. They figured out they did not need it. Look up on W/M website under tech lit for GV boilers and you will find the service bulleting or just call tech support. Tim

kpc_43

Checked the boiler...

pressure. 12 psi. Replaced prv... all was well for 8 hours then is peed all a over the place.... indire t was shut off from system for 1/2 3/4 of an hour. still leaked. aarrgh!

ata

...

is it possible that your feeder is weak and when ur pump comes on it is pulling water thru feeder??

Charlie from wmass

CHeck the indirect for an internal leak. SHut off feed to indirect on the domestic water side. I had this before. The manufacturer replaced the tank under warranty. Good luck.

Steve M_2

any luck?

Just curious, did you find the problem?

kpc_43

yup.

right out of the box no air in the new extrol... pumped it up to 20# all is fine. serves me right for not having a tire press.ga. on the truck. ty,kpc

Mitch_6

I f your high limit is working properly and

your pressure gauge is good and your indirect has not leak.

standard relief valve discharge service call. What we call a wet side tune up.

New compression tank

New auto feed / back flow

and

New pressure relief valve. by prv are we talking pressure reducing or pressure relief, as we all know once they go off they do not re seal.

GV's do have a tendency to plug up also.

Are you watching the pressure as the system heats.



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

kpc_43

that was the

strange thing. the pressure did not move much. MAX 25 psi.