roger_northeast
New Member
This is a long msg but please read it and provide me with your expertise where you can.
Thanks.
Roger
---------
I'm in the process of building a new house. I want to make sure that they size the hot water and domestic water storage correctly. Below is a description of all water usage
------------
Master Bath:
Custom shower: 3 body sprays, a rainshower head, 1 regular shower head and a hand-held shower. I'm using a Grohe Thermostatic valve 34-124 which has a maximum GPM of 18 at 45PSI. I'm putting in 4 Grohe 29274 volume controls, one for each function. All valves are 3/4". A realistic expectation is to have all going except the hand-held shower. I got a wife who likes to take long showers ~30mins.
Whirlpool tub: Tub filler 13gpm at 45psi and handheld 2.5gpm at 80PSI. Capacity: 96g
1 toilet, 1 bidet, 2 sinks
-----------
Bath # 2: Standard Tub, 1 sink, 1 toilet
-----------
Bath # 3: Standard shower, 2 sinks, 1 toilet
----------
Basement Bath: Standard Shower, 1 sink, 1 toilet
--------
1/2 bath #1: sink + toilet
--------
1/2 bath #2: sink + toilet
-------
Kitchen: 2 dishwashers, 1 sink
-----------
Laundry: 1 washer + 1 sink
----------
Exterior: 4 sillcocks
-----------
Hot Water: Indirect Buderus ST-200, 53g with a 2nd hour rating of 3.3gpm (I called the manufacturer and they told me they don't have the 1st hr rating, I thought this was a mandatory DOE rating, am I wrong?)
-------------
Water source: Well, well tank (to be sized), well produces about 5gpm. Pressure can be set 40 low and 60 max.
-------------
Irrigation system: Want to have this but don't know if system can handle it.
------------
Peak hour usage: Master bath in use for 30mins with body sprays, rainshower & shower head, followed by another 15 mins usage of rainshower. During this time, at least one of the other showers could be going and possibly two. At the very least 2 sinks will be used for ~5 mins each during that time.
Questions:
0) What do you estimate is the GPM of HW that I will need?
It looks to me that the provided HW indirect at 53g with a 3.3gpm production was not the right size to have provided.
1) What is your opinion?
That unit has been purchased now so I can only add to this. I was thinking adding another ST-200 and hooking both together. That would give me 106g to draw from in the first hour and a production of 6.6gpm
2) How should the tanks be hooked together, in series or parallel?
3) Could I really get 6.6gpm by putting 2 together?
A likely problem is that I may not have the BTUs in my boiler to keep two indirects going so another solution I was thinking of is to add a hot water storage tank, say 80g, just off the existing ST-200. This will require installing a re-circ pump between the ST-200 and the storage tank, but at least I get 133g before the indirect has to start producing.
4) Would this be a good solution that would provide the required GPM that I need?
5) Why do manufacturers list GPM at 80PSI? Most of the valves and other components in the system don't appear to support such high pressure.
6) What would a realistic GPM of a valve rated at 80psi be if I kept the pressure around 60PSI?
7) What's the formula for converting PSI to GPM? Is it simply a linear conversion? That is, at 40PSI the GPM would be 2.5/2?
Another problem that I have is that my well only produces 5gpm so I need to have a large reserve to supply all the above fixtures.
8) How do I properly size the well tank?
Pressure is very important. Right now in the house that we live in, if you flush a toilet or open a faucet, the shower head flow drops to a trickle. Also, the hot water goes to the faucet and as a result the person showering gets a cold shock.
9) Why do these problems happen and how do I prevent them from occuring in my new house?
10) Is it a matter of the height of the pipes? That is, is the sink always going to have a preference to the shower because it is lower?
11) Would a pressure booster pump resolve this issue?
A pressure booster pump can take my well pressure and increase to a constant 80psi (according to the literature I just read). However, it looks like most valves can only handle up to 72psi. At least the ones that I found specs for (the ones in the master bath)
12) What's the typical pressure max for contractor valves? For example, the valves he'll install in the sinks?
13) What other fixtures would limit the max pressure? For example, does the washer or ice-maker have a lower max and therefore, force me to keep the pressure below 70psi?
14) Can the copper tube handle the 70PSI day in and day out?
Thank you for all of your help.
Roger
Thanks.
Roger
---------
I'm in the process of building a new house. I want to make sure that they size the hot water and domestic water storage correctly. Below is a description of all water usage
------------
Master Bath:
Custom shower: 3 body sprays, a rainshower head, 1 regular shower head and a hand-held shower. I'm using a Grohe Thermostatic valve 34-124 which has a maximum GPM of 18 at 45PSI. I'm putting in 4 Grohe 29274 volume controls, one for each function. All valves are 3/4". A realistic expectation is to have all going except the hand-held shower. I got a wife who likes to take long showers ~30mins.
Whirlpool tub: Tub filler 13gpm at 45psi and handheld 2.5gpm at 80PSI. Capacity: 96g
1 toilet, 1 bidet, 2 sinks
-----------
Bath # 2: Standard Tub, 1 sink, 1 toilet
-----------
Bath # 3: Standard shower, 2 sinks, 1 toilet
----------
Basement Bath: Standard Shower, 1 sink, 1 toilet
--------
1/2 bath #1: sink + toilet
--------
1/2 bath #2: sink + toilet
-------
Kitchen: 2 dishwashers, 1 sink
-----------
Laundry: 1 washer + 1 sink
----------
Exterior: 4 sillcocks
-----------
Hot Water: Indirect Buderus ST-200, 53g with a 2nd hour rating of 3.3gpm (I called the manufacturer and they told me they don't have the 1st hr rating, I thought this was a mandatory DOE rating, am I wrong?)
-------------
Water source: Well, well tank (to be sized), well produces about 5gpm. Pressure can be set 40 low and 60 max.
-------------
Irrigation system: Want to have this but don't know if system can handle it.
------------
Peak hour usage: Master bath in use for 30mins with body sprays, rainshower & shower head, followed by another 15 mins usage of rainshower. During this time, at least one of the other showers could be going and possibly two. At the very least 2 sinks will be used for ~5 mins each during that time.
Questions:
0) What do you estimate is the GPM of HW that I will need?
It looks to me that the provided HW indirect at 53g with a 3.3gpm production was not the right size to have provided.
1) What is your opinion?
That unit has been purchased now so I can only add to this. I was thinking adding another ST-200 and hooking both together. That would give me 106g to draw from in the first hour and a production of 6.6gpm
2) How should the tanks be hooked together, in series or parallel?
3) Could I really get 6.6gpm by putting 2 together?
A likely problem is that I may not have the BTUs in my boiler to keep two indirects going so another solution I was thinking of is to add a hot water storage tank, say 80g, just off the existing ST-200. This will require installing a re-circ pump between the ST-200 and the storage tank, but at least I get 133g before the indirect has to start producing.
4) Would this be a good solution that would provide the required GPM that I need?
5) Why do manufacturers list GPM at 80PSI? Most of the valves and other components in the system don't appear to support such high pressure.
6) What would a realistic GPM of a valve rated at 80psi be if I kept the pressure around 60PSI?
7) What's the formula for converting PSI to GPM? Is it simply a linear conversion? That is, at 40PSI the GPM would be 2.5/2?
Another problem that I have is that my well only produces 5gpm so I need to have a large reserve to supply all the above fixtures.
8) How do I properly size the well tank?
Pressure is very important. Right now in the house that we live in, if you flush a toilet or open a faucet, the shower head flow drops to a trickle. Also, the hot water goes to the faucet and as a result the person showering gets a cold shock.
9) Why do these problems happen and how do I prevent them from occuring in my new house?
10) Is it a matter of the height of the pipes? That is, is the sink always going to have a preference to the shower because it is lower?
11) Would a pressure booster pump resolve this issue?
A pressure booster pump can take my well pressure and increase to a constant 80psi (according to the literature I just read). However, it looks like most valves can only handle up to 72psi. At least the ones that I found specs for (the ones in the master bath)
12) What's the typical pressure max for contractor valves? For example, the valves he'll install in the sinks?
13) What other fixtures would limit the max pressure? For example, does the washer or ice-maker have a lower max and therefore, force me to keep the pressure below 70psi?
14) Can the copper tube handle the 70PSI day in and day out?
Thank you for all of your help.
Roger