re: anon 11:49 and master plumbers response
We have this situation in our co-op brownstone. Water being heated by our boiler. As our brownstone has been broken up into apts. we have many more people living here than say a brownstone with an apt.
We would run out of hot water. Master plumber recommended putting in a hot water storage tank to handle the demand. We did that. No more hot water complaints.
Anonymous 11:49 AM:
You have a tankless coil, not a “tankless heater”. They’re very different and yours is one of the least efficient ways to heat domestic hot water. On the plus side, yours is a very simple, time-tested device that does the job reliably.
TinMouse10:
I like the idea of giving all your tenants their own high-efficiency water heater connected to their own gas meter. It’s definitely the European way.
rendak:
You’re right that they don’t rust out. They do clog up, though. Most manufacturers recommend some type of periodic decalcification procedure. They also tend to have shorter warranties than tank-type products.
Anonymous 12:55 PM:
In order for a “tempering tank” to do what you intend it to do, it would have to either heat the water electrically or with fuel or it would have to sit uninsulated and absorb warmth from the surrounding air. Having it use energy to heat the water would defeat the purpose of the system. Having an uninsulated tank of cool water sit in warmer surroundings would produce condensation, which would have to be dealt with. A sweating steel tank would rot away very quickly, and to make the tank out of stainless steel/brass/copper would be too costly. Either way, once the water was turned on, the tank would cool so quickly, it would put you right back where you started and not be worth the expense.
Anyway, you’re actually on to something.
What I’ve done in the past, especially in commercial applications, is use a small insulated electric buffer tank on the outlet of the heater to absorb some of the temperature swings associated with tankless use.
This forgives a lot of tankless sins and also allows for the installation of a hot water recirculation line for buildings where some fixtures are farther than 50 feet from the heat source, which is required by code.
Also, as the tank is being supplied with hot water, it’s electric heating elements rarely ever turn on.
Anonymous 1:49 PM:
Electric tankless water heaters require a lot of power. More than you might have available in your 80-year-old home. And they cost more to run than gas-burning heaters. BUT! They’re a cheap purchase/installation/replacement and save space.
I haven’t heard of tempering tank – am dubious that you could get sufficient heat transfer in the time water would sit in the tank without some pump circulating water thruogh a heat exchanger in the rm – big pain.
Instead consider using an insulated storage tank (can be got with very low heat loss/high effiency, eg Superstor at some cost) for the hot water -> gives buffer for periodic higher hot water consumption than tankless can provide.
Master plumber, what are your thoughts on using a tempering tank to allow water from the main to get up to room temperature prior to entering the tankless unit?
For instance, if water is coming in to the house at 40 degrees, let it sit in a tank in the basement – or maybe even the boiler room – to get up to 60-70 degrees so that the flow rate can be higher.
I have a propane Bosch tankless at my cabin upstate and a electric Seisco unit for the apartment upstairs in our BedStuy brownstone. They both work very well. The electric unit requires no exhaust and is IN the bathroom instead of 40 feet away in the cellar, so the hot water is much quicker to arrive.
Tankless water heaters take up a lot less room, they use no energy when the water’s not running, they don’t rust out, the hot water’s endless… what’s not to love?
I bought the Seisco new on eBay (with the warranty) for $500.
Someday I’ll replace the big dumb tank unit for our duplex with another electric tankless.
Good luck
Reno D.
I have a boiler with a heating coil (i think that’s what its called) for hot water. From my understanding its a tankless system and I love it. As master plumber said sometimes you will have to wait a few seconds for water to heat up but once it does you can sit in a shower for as long as you like with plenty of hot water. I have a tenant and i have never had any situation where i could not get hot water. Maybe we shower at different times but who knows. Both my husband and i have lived in places with hot water heaters and the tankless kind and i have to say there is no comparison between the two. Tankless is just so far superior!!
I own a 2-family in lower Windsor Terrace and am aware that soon we’ll have to replace the hot water tank and furnace. I was thinking about installing 2 separate instant hot water systems, one per unit. When I lived in Europe we had one per kitchen, one per bathroom! The good thing is that they are very very small–installed above a toilet, and installed in the pantry cupboard (both on exterior walls). Is it worth considering doing separate installations for a 2-family where both units are rented out? I’m looking to save money long-term on heat and hot water costs, and would rather have the tenants pay their own costs than have to raise rent substantially. It would also encourage the tenants to be more conservation minded?
While I’m at it, anyone have any experience with re-roofing a flat roof in a rental with more green materials? My plan is to go green with each renovation project, both in our home and the property we rent out. I’d love some thoughts on that one!
re: anon 11:49 and master plumbers response
We have this situation in our co-op brownstone. Water being heated by our boiler. As our brownstone has been broken up into apts. we have many more people living here than say a brownstone with an apt.
We would run out of hot water. Master plumber recommended putting in a hot water storage tank to handle the demand. We did that. No more hot water complaints.
Anonymous 11:49 AM:
You have a tankless coil, not a “tankless heater”. They’re very different and yours is one of the least efficient ways to heat domestic hot water. On the plus side, yours is a very simple, time-tested device that does the job reliably.
TinMouse10:
I like the idea of giving all your tenants their own high-efficiency water heater connected to their own gas meter. It’s definitely the European way.
rendak:
You’re right that they don’t rust out. They do clog up, though. Most manufacturers recommend some type of periodic decalcification procedure. They also tend to have shorter warranties than tank-type products.
Anonymous 12:55 PM:
In order for a “tempering tank” to do what you intend it to do, it would have to either heat the water electrically or with fuel or it would have to sit uninsulated and absorb warmth from the surrounding air. Having it use energy to heat the water would defeat the purpose of the system. Having an uninsulated tank of cool water sit in warmer surroundings would produce condensation, which would have to be dealt with. A sweating steel tank would rot away very quickly, and to make the tank out of stainless steel/brass/copper would be too costly. Either way, once the water was turned on, the tank would cool so quickly, it would put you right back where you started and not be worth the expense.
Anyway, you’re actually on to something.
What I’ve done in the past, especially in commercial applications, is use a small insulated electric buffer tank on the outlet of the heater to absorb some of the temperature swings associated with tankless use.
This forgives a lot of tankless sins and also allows for the installation of a hot water recirculation line for buildings where some fixtures are farther than 50 feet from the heat source, which is required by code.
Also, as the tank is being supplied with hot water, it’s electric heating elements rarely ever turn on.
Anonymous 1:49 PM:
Electric tankless water heaters require a lot of power. More than you might have available in your 80-year-old home. And they cost more to run than gas-burning heaters. BUT! They’re a cheap purchase/installation/replacement and save space.
Can you tell I’m really into this stuff?
Master plumber,
Is it safe to say I would avoid the disadvantages you mentioned by using an electric tank less water heater?
Thanks
Master plumber,
Is it safe to say I would avoid the disadvantages you mentioned by using an electric tank less water heater?
Thanks
I haven’t heard of tempering tank – am dubious that you could get sufficient heat transfer in the time water would sit in the tank without some pump circulating water thruogh a heat exchanger in the rm – big pain.
Instead consider using an insulated storage tank (can be got with very low heat loss/high effiency, eg Superstor at some cost) for the hot water -> gives buffer for periodic higher hot water consumption than tankless can provide.
Master plumber, what are your thoughts on using a tempering tank to allow water from the main to get up to room temperature prior to entering the tankless unit?
For instance, if water is coming in to the house at 40 degrees, let it sit in a tank in the basement – or maybe even the boiler room – to get up to 60-70 degrees so that the flow rate can be higher.
Is this ever done? Are there downsides?
I have a propane Bosch tankless at my cabin upstate and a electric Seisco unit for the apartment upstairs in our BedStuy brownstone. They both work very well. The electric unit requires no exhaust and is IN the bathroom instead of 40 feet away in the cellar, so the hot water is much quicker to arrive.
Tankless water heaters take up a lot less room, they use no energy when the water’s not running, they don’t rust out, the hot water’s endless… what’s not to love?
I bought the Seisco new on eBay (with the warranty) for $500.
Someday I’ll replace the big dumb tank unit for our duplex with another electric tankless.
Good luck
Reno D.
I have a boiler with a heating coil (i think that’s what its called) for hot water. From my understanding its a tankless system and I love it. As master plumber said sometimes you will have to wait a few seconds for water to heat up but once it does you can sit in a shower for as long as you like with plenty of hot water. I have a tenant and i have never had any situation where i could not get hot water. Maybe we shower at different times but who knows. Both my husband and i have lived in places with hot water heaters and the tankless kind and i have to say there is no comparison between the two. Tankless is just so far superior!!
I own a 2-family in lower Windsor Terrace and am aware that soon we’ll have to replace the hot water tank and furnace. I was thinking about installing 2 separate instant hot water systems, one per unit. When I lived in Europe we had one per kitchen, one per bathroom! The good thing is that they are very very small–installed above a toilet, and installed in the pantry cupboard (both on exterior walls). Is it worth considering doing separate installations for a 2-family where both units are rented out? I’m looking to save money long-term on heat and hot water costs, and would rather have the tenants pay their own costs than have to raise rent substantially. It would also encourage the tenants to be more conservation minded?
While I’m at it, anyone have any experience with re-roofing a flat roof in a rental with more green materials? My plan is to go green with each renovation project, both in our home and the property we rent out. I’d love some thoughts on that one!