My latest project: HPWH

JakeCK

So my current water heater is pushing 14+ years. And I discovered a while back that the flue it vents in to has been open for years to a stud bay in the kitchen where the wood or coal stove used to vent. Previous HO had covered the hole in the plaster with a metal pie plate and then plastered over that. As a consequence of the age of the current tank, the need for the flue to be relined, and the just finished solar installation (110% offset), I decided to go with a Heat pump water heater as a replacement. This would also allow me to tear down 1 of 3 chimney's(initially to just below the attic floor) reducing heat loss even further. There is also the added benefit of dehumidification and cooling of the basement in the summer. Currently I run a dehumidifier Late April/early May to October, and it raises the temperature quite a bit down there. 

Now with that all out of the way here is what I have so far: Everything is dry fitted so changes would be easy. Old tank is still hooked up but I've shut off the gas so I'm not wasting energy. 

Any glaring mistakes I should correct before I pull out the old tank? Also no I have not been running the old tank with out a pipe on the T&P valve. I moved it to the new tank. 

 Unfortunately I'll probably be forced to use a sharkbite for the two connections to the existing water lines. There is cat6, a gas line and a joist right where I would have to sweat the pipe. 

I also need to order the intake kit so I can have it pull air from the main room with the boiler in it.

JakeCK

Hope I got it all right because it's plumbed in now. So far working excellent. Although I must admit if I had to redo it I would skip the tempering valve. At least on the near tank plumbing. Not a single one of my sweated joints leaks. But the unions on that valve sure did. 


Still need to bond between the hot and cold.

HVACNUT

The domestic extrol should be on the cold side. 
If the relief valve needs replacing, will it unthread before hitting the wall?

JakeCK

For the expansion tank, is there any reason other then heat loss? The only reason I put it where I did was because of where the valve is.

T&p valve should clear, it is out before the wall. If not a minor movement of the tank will allow it. Is it the same length as the one in my RV's tank?

GW

if you can solder that well, why use the flex? No vacuum breaker?

EBEBRATT-Ed

@GW

Vacuum breaker is a MA thing. Good idea I think but other states don't require it CT for instance.

GW

Ed wow didn't know that, good to keep in the back of my noggin

JakeCK

GW said:

if you can solder that well, why use the flex? No vacuum breaker?

Those are good solder joints? Look like S*** to me, I'll take it as a compliment. Soldering is an art form, and I drew stick figures in art.

I thought vacuum breakers were only needed if the tank was above the faucets. Like on a second floor or attic?

And the flex to make it easier to connect to the lines by the ceiling.

KC_Jones

GW said:

if you can solder that well, why use the flex? No vacuum breaker?

If Gary is complimenting your soldering, that is high praise.

He's posted his work, as well as a video of him soldering, he's quite talented.

GW

well, the flex is 'less appealing'. Many guys can't solder that well. My favorite soldering story is back in '87, my then-boss barked across the shop "WILSON you gotta get back to abc street, Inspector shot you down for not soldering the tub valve" (new construction,first floor, we didn't test that 1st fl stuff). So i drive over there and yes the valve was soldered, i guess the Inspector didn't have his reading glasses on.

Vac breakers-- if the fireman is pulling on the lines in the street, you could lose your tank, then tank could 'implode'. At least that what was explained to be way back, (prior to 1987), never seen it with my own eyes.

JakeCK

GW said:

well, the flex is 'less appealing'. Many guys can't solder that well. My favorite soldering story is back in '87, my then-boss barked across the shop "WILSON you gotta get back to abc street, Inspector shot you down for not soldering the tub valve" (new construction,first floor, we didn't test that 1st fl stuff). So i drive over there and yes the valve was soldered, i guess the Inspector didn't have his reading glasses on.

Vac breakers-- if the fireman is pulling on the lines in the street, you could lose your tank, then tank could 'implode'. At least that what was explained to be way back, (prior to 1987), never seen it with my own eyes.

I really like the flexibility provided by the flex lines. And it still looks better then the cluster that was piped in before. It took me hours to solder those up, between deburring and cleaning the ends. I actually did all of that on the tailgate of my truck. It was a beautiful day yesterday and I don't like using a torch in the house if it can be avoided.

GW

I’m feeling that, we pipe heads just sweat it all in place. Looks good though

GW

Hopefully this makes somebody smile, I took a picture of this recently, not sure if it was for my own edification or some other motivation. I despise couplings so I unsweat the ugger and soldered in a longer piece. 

Everything was lovely, until about 45 minutes I saw drip coming off of it. I’m like son of a gun, I thought that joint came out pretty nicely. Upon further inspection the ball valve was leaking where the body is threaded together.

So, we cut it out and pinched in a new valve. Sometimes you just can’t win.

delta T

JakeCK said:

GW said:

I thought vacuum breakers were only needed if the tank was above the faucets. Like on a second floor or attic

My code requires a vacuum breaker on all bottom fed tanks, regardless of where they are installed.

JakeCK said:

For the expansion tank, is there any reason other then heat loss?

Yes. The bladder on the expansion tank will last much longer if it is only exposed to cold water. Not sure of local codes where you are, but in my code it is required to be on the cold side.

JakeCK

delta T said:

I thought vacuum breakers were only needed if the tank was above the faucets. Like on a second floor or attic

My code requires a vacuum breaker on all bottom fed tanks, regardless of where they are installed.

For the expansion tank, is there any reason other then heat loss?

Yes. The bladder on the expansion tank will last much longer if it is only exposed to cold water. Not sure of local codes where you are, but in my code it is required to be on the cold side.

Then it sounds like I have some rework to do.

It'll probably be a few weeks or a month before I have another free weekend. Unless I can find time during the week. 

JakeCK

Now the question is what is the best way to seal the hole in the old chimney. Both the three inch from the old hot water tank and this 8"

Kafox15

I am in the process of installing the same/similar tank. Is a mixing valve required in MA?

Also, what is the correct order for the cold water supply from where I branch off to the heater?  Shut off -> expansion tank ->vacuum breaker -> cold water inlet on water heater?

Kafox15

Looking for some feedback on my HPWH install as well. Willing to start a separate thread if that's preferred, but I think its relevant here. I still need to add a condensate drain, bond the hot + cold, and move my mixing valve from my old tankless coil setup to the new setup (waiting on 3/4 unions for the honeywell AM-1). Where is the correct place on the hot and cold to cut in the mixing valve? Thanks!

JDHW

If a fireman pulling water from mains does drop the pressure below atmospheric wouldn't that mean potential for ground water to be pulled into the mains? That does not sound good to me.

John

JakeCK

Kafox15 said:

I am in the process of installing the same/similar tank. Is a mixing valve required in MA?

Also, what is the correct order for the cold water supply from where I branch off to the heater?  Shut off -> expansion tank ->vacuum breaker -> cold water inlet on water heater?

I think a mixing valve is required when ever there is water over 120f.

Kafox15

Yea, I am planning to add one regardless. Just not sure where the best place to cut it in on the cold side is. On the tank side or supply side of the vacuum breaker/expansion tank?

Larry Weingarten

Hi @Kafox15 , I'm not sure there is any difference in performance between installing cold feed to a mixer before or after the vacuum breaker. I would suggest adding a ball valve with a waste port between the piping and expansion tank (waste port towards the tank), so you can test and adjust the tank easily. Maybe while doing that, you could tie into the line for your cold feed to the mixer.

Yours, Larry

Kafox15

Thanks @Larry Weingarten Do you mind clarifying where I would add another ball valve with waste? Are you talking about dropping the expansion tank lower and adding it below the expansion tank tee?

Larry Weingarten

Yes, Exactly. just lower the tank to fit in that ball valve and perhaps a "T" for the cold feed to the mixer.

Yours, Larry

Kafox15

got it - I may end up doing the mixing valve closer to the water heater side if location truly doesn't matter. Just because there is less "stuff" in the way to contend with. Appreciate the advice.

JakeCK

As a continuation of my HPWH install: Chimney removal!

Demo is my favorite part!

Anyone ever see this kind before where above the roof is brick with clay liner but starting in the attic it is some type of concrete sections with integrated liner?

Also I paid a crew to take it down above the roof and patch because I don't do heights. The rest in the attic I handled. The crew told me they found water between the flashing and bricks and that the flashing was in good shape. And I discovered that the whole thing is loose. I can rock it back and forth in the wall. I do not know if it happened during demo or not. It was going to need attention one way or another.

ChrisJ

Those flex lines are making us DIYers look bad.

Why the addition of an expansion tank? Are you doing a PRV or backflow that didn't exist before?

Kafox15

ChrisJ said:

Those flex lines are making us DIYers look bad.

Why the addition of an expansion tank? Are you doing a PRV or backflow that didn't exist before?

Not OP but the manual for this water heater actually specifies flexible connections.

JakeCK

ChrisJ said:

Those flex lines are making us DIYers look bad. Why the addition of an expansion tank? Are you doing a PRV or backflow that didn't exist before?

Those have both existed on the house since before I bought it. I could always tell when the tank had heated a lot of water by how much harder it blasted out of the faucet.

And flex lines are not only permitted by code but are used by professionals and diyers alike and are actually required by code in some jurisdictions i believe.

JakeCK

And that isnt the final install. Im going to end up replumbing the whole basement. 

ChrisJ

The water heater actually requires flexible connections?

Can Pex be used?

Kafox15

Not specifically required but recommended. Excerpt below from the manual.

"The installation of flexible connectors is recommended on the hot and cold water connections. Flexible connections provide vibration isolation and allow the water heater to be easily disconnected for servicing if necessary."

Yes, PEX is mentioned as a type of flexible connection.

JakeCK

ChrisJ said:

The water heater actually requires flexible connections? Can Pex be used?

I do not believe pvc or pex can be used has to be flexible copper or stainless. But don't quote me on that.

JakeCK

Kafox15 said:

Not specifically required but recommended. Excerpt below from the manual. "The installation of flexible connectors is recommended on the hot and cold water connections. Flexible connections provide vibration isolation and allow the water heater to be easily disconnected for servicing if necessary." Yes, PEX is mentioned as a type of flexible connection.

In earth quake country I believe flexible copper is required to allow for movement between the tank and plumbing. Even with the strapping required.

Kafox15

I did not end up using any flex in my install, mostly because it was much more accessible than @JakeCK 's but did consider it based on the recommendations in the manual (and regretted not doing it when soldering all the joints around the mixing valve).

ChrisJ

JakeCK said:

Kafox15 said:

Not specifically required but recommended. Excerpt below from the manual.

"The installation of flexible connectors is recommended on the hot and cold water connections. Flexible connections provide vibration isolation and allow the water heater to be easily disconnected for servicing if necessary."

Yes, PEX is mentioned as a type of flexible connection.

In earth quake country I believe flexible copper is required to allow for movement between the tank and plumbing. Even with the strapping required.

Are you in earth quake country?

Pex is most certainly flexible and flows far better than that corrugated copper stuff.
Pex A is especially flexible. This is primarily what I've been using lately though when I did my water heater I soldered all of it. Gas line is black iron and threaded right to the regulator.

Some codes may not allow pex directly to a water heater, though Uponor themselves do allow it as long as it's not near a draft hood or flu that could overheat the pex.

JakeCK

No I'm not. I was only using it as an example. But as kafox said on heat pumps it is recommended for vibration control. Just like my window shaker ac it has a compressor and does produce some vibration. Those of us lucky enough to have a basement or concrete floors dont have much to worry about though.

ChrisJ

JakeCK said:

No I'm not. I was only using it as an example. But as kafox said on heat pumps it is recommended for vibration control. Just like my window shaker ac it has a compressor and does produce some vibration. Those of us lucky enough to have a basement or concrete floors dont have much to worry about though.

That's a really good point actually, a normally WH doesn't vibrate generally.

I didn't think of that.

JakeCK

One item struck off the list:

Insulated with 5" of polyiso foam board and can foamed in. I had to build up with 1" foam boards because that was all that Menards had besides 1/2". Hd was out and so was lowes. Almost to code minimum on insulation. And leagues above the 5" or so of blown fiberglass. Also added a 2x2 to give a little extra support for the boards the 28" span made me nervous if something heavy hit it