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[woodywoodchucker]

Has anyone been running there boiler without the bypass valve and then added one to there system? If so what where the results.

[pwdiver]

Im not sure what you mean by bypass valve, mine has been running none stop since 2009 because I use it for my hot water also, I close off the inlet valve to my heat exchanger for the heat pump and water continues to circulate through my plate exchanger for the hot water.

[woodywoodchucker]

there is a by pass valve that is installed in the piping to  the pump. If your boiler water starts to go below 160 the valve starts to close and completely closes at 140.It's to keep the boiler from producing condensate.
 I thought it would help me with the fact that I work 12 hour shifts and the boiler has to go 14 hours on one feeding. with temp well below 0 its a stretch to say the least.

[pwdiver]

I havent heard of a bypass valve but got up this morning and new that the boiler must be out, went outside this morning and the water temp was 90 degree's It took me 2hr's to get the boiler going I went ahead and cleaned it out. I did see some condensate dripping  from the door.  But once it got hot that stopped.

[willieG]

i have never seen my water below 150 unless i forgot to add wood..i cant see where you would need this valve unless your stove is too small for your heat load?

and if your stove got below 150 for a few hours now and then i cant see rust occuring that fast. i just don't buy it..

i know i could be very very wrong here but after seeing what the inside of my old stove looked like i dont think i will ever consider using one

[dwneast77]

The "bypass" valve he's referring to is called a Thermostatic Valve.  I have one installed on my main line that feeds my greenhouses since they pull so much heat so fast.  I didn't bother setting it up for my house so far, but CB sent me one for free, so I have it.  It prevents the water from dropping below 150 by returning the water to the boiler and not letting it pass to the HX.  Mine is set at 150 anyway.  Between 150 and 170 it allows partial flow to the HX and at 170 it opens fully to the HX.  As far as results, well, it does what it says.  I've run my water temp down and the valve does what it is suppsed to do allowing the boiler time to recover.   Other than that, you shouldn't even notice it's there.

[Roger2561]

I too have the thermostatic valve on the piping of my CB E-classic 1400.  I essentially use it as an early warning device.  If the water temp gets below 150 my oil furnace kicks on.  I will hear the oil furnace come on even if I'm sleeping.  I'll get up and investigate the cause.  Once I lost the fire over night - not enough of a coal bed to support the amount of wood I put in it.  The second time the wood bridged and lost the fire.  Both times my oil furnace woke me up.  By not letting my water temp get below 150, it recovers to high temp within 20 to 30 minutes.  Before going outside to investigate the cause, I turn off the thermostats in the house so there is no load on the OWB or oil furnace.  This will allow the OWB water to recover rather quickly and I'm not burning any oil.  It cost to much.   Roger

[loneryder]

there is a by pass valve that is installed in the piping to  the pump. If your boiler water starts to go below 160 the valve starts to close and completely closes at 140.It's to keep the boiler from producing condensate.
 I thought it would help me with the fact that I work 12 hour shifts and the boiler has to go 14 hours on one feeding. with temp well below 0 its a stretch to say the least.

They are supposedly required for CB's warranty.  My dealer left it out.  Since I have a heat pump and have to travel at times, we looped the HW line from the boiler thru the DHW exchanger to a 3 way aquastat which only allows HW to the furnace exchanger when heat is called for.  So if I'm not there and it falls below 140 the electric heat takes over. Boiler water is not going thru the furnace.  Over these holidays I've been gone a lot so I switched the thermostat to heat pump and just let the HW water circulate to the house and back without going thru the furnace.  3 days later the water temp was 151 and there were hot coals left..enough to fire up a new supply of wood.  I think that valve would hurt your cause with 12 hr days.  What kind of secondary heat do you have?

[woodywoodchucker]

I have a Baxi gas furnace.The wood boiler uses a HX. the water from the HX and the Baxi go through a hydraulic separator.I have radiant in the basement and first floor and and base board up stairs.

[johnybcold]

I do not have the thermo valve, it was a option when I got my unit now you need it or it voids the CB warranty , I see the point of it but to me it is just another thing in the system, my thoughts when installing was to get the most direct uninterrupted path the my old furnace

[muffin]

Has anyone been running there boiler without the bypass valve and then added one to there system? If so what where the results.

I have one, but it was installed initially per warranty requirements.  I suppose if it save the boiler it is good, but it is a pain in the butt.  It is for the return water which is not hard to get below the 160F threshold.  Then it starts shunting the supply to the return which makes it worse as your flow rate to the house is decreased so the temp drop gets even worse.  I guess I need everything in parallel and not series, i dunno.  I am probably going to have to do that, but that will require additional pumps.

[boilerman]

CB's thermostatic valve works off incoming supply temps, not return temps. As long as supply water comes in over 170 degrees you get 100% flow. If OWF can't keep up with load or you're out of wood and supply water at valve drops below 170, water to exchanger will gradually be cut back, more and more will get sent back to OWF as supply water drops down to 150 degrees. Even at 150 or below, enough water will still be allowed to run through exchanger to back heat from exchanger from back up indoor heat to keep water lines and OWF from freezing as long as circ pump continues to run. Valve operation is explained in their later owners manuals.