Weil-McLain 550-141-827/1201 Boiler User Manual


 
Cold
Hot
Mixed
Automatic
Mixing
Valve
Studies have indicated that
dangerous bacteria can form in
potable water distribution system if certain minimum
water temperatures are not maintained. Contact local
health department for more information.
To pipe tankless heater:
1. Size piping no smaller than tankless heater
inlet and outlet.
2. Following controls (furnished by others) must
be installed:
a. Automatic mixing valve. See FIGURE 14.
(Read at bottom of p. 16)
b. Flow regulating valve. Size according to
intermittent draw of tankless heater. See
Table at right. Follow valve manufacturer’s
instructions to install.
3. Additional anti-scald devices may be installed at
each hot water faucet, bath and shower outlet.
4. In hard water areas, soften cold domestic supply
water to heaters to prevent lime build-up.
These single wall heat exchangers
comply with National Standard
Plumbing Code provided that:
Boiler water (including
additives) is practically non-
toxic, having a toxicity rating
or class of 1, as listed in
Clinical Toxicology of
Commercial Products.
Boiler water pressure is
limited to max. 30 psig by
approved water relief valve.
17
Connect Tankless Heater Piping CONTINUED
Tankless Heater Piping
FIGURE 14
Tankless Heater
Control
Flow
Regulating
Valve
Cold
Water
Supply
TANKLESS HEATER RATINGS TABLE
BOILER INTERMITTENT INLET
MODEL HEATER DRAW RATINGS AND OUTLET
NUMBER NUMBER (GPM)* TAPPING SIZES
SGO-3W 35-S-29 3.50 ¾"
SGO-4W 35-S-29 3.75 ¾"
SGO-5W 35-S-29 4.00 ¾"
SGO-6W 35-S-29 4.00 ¾"
SGO-7W 35-S-29 4.00 ¾"
SGO-8W 35-S-29 4.00 ¾"
SGO-9W 35-S-29 4.00 ¾ "
* Gallons of water per minute heated from 40°F to 140°F with
200°F boiler water temperature. Tested in accordance with
I=W=H Testing and Rating Standard for Indirect Tankless Water
Heaters Tested with Boilers.
12" Min.